электроника – запуск цифровых индикаторов

и несколько примеров конструкций – самодельных

http://www.tuxgraphics.org/electronics/200606/article06061.shtml

Introduction to the ENC28J60 Ethernet controller

The ENC28J60 from Microchip is a fantastic chip. It has Tx/Rx, MAC and PHY in one small chip. There are very few external parts. Basically just a crystal and an Ethernet transformer, aka magnetics. All this comes in an convenient 28-pin DIP package. Easy to solder and perfect for hobby applications.


Figure 1: Schematic block diagram.

The microcontroller can then control any hardware you like: You can attach some sensor (light, temperature), you can switch on an off something you can attach a LCD display, etc…

https://www.benshobbycorner.tk/bzijlstra/software/examples/enc28j60.htm

немножко про механические часы ( ну парочка есть на сайте rusantikvar и то одни кажется на Украине)

Molnija pocket watches

I have started this page because I like pocket watches. Russian Molnija watches are robust, good quality watches and are still available second hand. I don’t speak or read Russian but I have some friends that do and sometimes I ask them for help.

Why pocket watches?

I never really liked wrist watches and I used to carry my wrist watch in the pocket or I would just not carry any watch at all. I retired my watch when small GSM mobile phones came up. All the phones had a built-in clock. I had no more need for an extra watch. Today smart phones are so big that they restrain you when carried in your pant’s pocket. Now I avoid smart phones and wrist watches in my spare time. I find it good to do something together with my family and be not reachable by phone. Thus I have re-discovered the good old mechanical watch.

As an engineer I find mechanical watches interesting from a technical point of view and we start with that aspect.

The Molnija mechanical movement

Molnija (Молния) pocket watches were made from 1947 to November 2007. The main factory was located in the Ural town of Chelyabinsk with a second factory outside of Moscow. The Russian word Молния means lightning.

A small group of people continued after the closure of the factory and they are trying to re-use the brand name for new watches. These new watches have not much in common with the original Molnija pocket watches.

The word “Молния” is pronounced like the English letter combination “Molnya”.

A communist society does not have the concept of competition between rival companies. Thus there is no need to innovate a lot and re-design all the time. This can be very bad for the advancement of technology when it evolves still a lot. Cars and computers did e.g go through massive changes between 1947 to 2007. Mechanical watch movements did however have the time of new technology and innovation much earlier. By 1947 is was pretty much known how to design a good mechanical watch (the famous Waltham Watch Company stopped production in 1949).

The Molnija movement is basically a copy of a Cortebert movement as used e.g in Rolex watches from around 1940. The Russians improved accuracy of the movement quite a bit when they upgraded it to their 18 jewels version of the movement but the basic design remained the same until the closure of the factory in 2007. In other words the Molnija movement was originally a Swiss Cortébert movement. A high quality movement.


From left to right: a 1940’s Rolex movement cal. 618, an old Molnija 15j movement, a Cortebert cal. 624 movement, a Cortebert cal. 616 movement.

This swiss movement design was very popular and a blueprint for many movement designs from that time. Here is a 1947 Bulova watch movement:

A 1947 bulova pocket watch

The fact that the Molnija movement changed very little over time does of course not mean that all Molnija watches were the same from 1947 to 2007.

Molnija watch from the first few month of production. Made end of 1947 in Moscow.


The early Molnija design. All Molnija watches produced just after 1947 until the mid 1950’s looked like this.

Even a communist society had a demand for more individual and different pocket watches and they changed them externally. The Molnija factory produced just one style in the early years but over time they came up with many different cases and dials. They changed as well the movements and you can not easily mix spare parts from different Molnija generations but overall the changes made to the movements where minor.

Molnija watches where sold in the 50’s and 60’s in nicely made card board boxes. In the 70’s and later small black-marble colored plastic boxes where used. I am not exactly sure when they switched the watches sold in the USSR from card board boxes to plastic. Jewelers outside the USSR selling those watches did often provide their own individual boxes and packaging.


Picture on the left: Molnija watch 15j, 1954 with papers and box. The two pictures to the right: Molnija watch 18j, 1974, with certificate and original box, front and back view of the watch and the certificate. Click on the photos for more details.

The Molnija movement is a good, robust and reliable mechanical movement. An advantage of having very similar movements in all Molnija watches from today’s point of view is that it is not difficult to find spare parts.

The movement is mainly made out of a nickel copper alloy. The smaller and more delicate cog wheels are made of brass and the bigger wheels which are directly connected to the main spring are made out of carbon steel.

Molnija technical specifications

Movement diameter: 36 mm

Movement types: early movements are called “ЧК-6” (ChK-6) and they have a nice striped pattern finish (Geneva stripes). Around 1964 a new movement called 3602 was introduced. The 3602 is almost identical to the “ЧК-6” but it has no finishing pattern and some of the internal dimensions are different such that you can not exchange parts between the two types. The 3603 movement is a 3602 movement with shock protection (the balance wheel jewels are different).

Jewels (gemstone bearings): normally 15 on the “ЧК-6” and 18 on the 3602/3603 movements

Rate: 2.5Hz, 5 beats per second, 18000 bph (beats per hour)

Main-spring reserve: The watch runs about 40 hours when fully wound.

Balance staff: riveted, note “ЧК-6” (ChK-6) and 3602/3603 movements require different staffs.

Balance wheel: The balance wheel alloy was changed and improved over the years. I have seen at least 3 different kinds of alloys with different colors in Molnija watches.

Hairspring material: Elinvar, hairspring form: Breguet overcoil for 3602/3603 and flat hairspring for ЧК-6

Russian words and symbols on Molnija watch dials


Russian Molnija watch with Молния written in script.

  • Молния — Molnija.

  • сделано в ссср — means Made in CCCP (Soviet Union).


Russian Molnija watch with “made in russia”.

  • сделано в россии — means Made in Russia. This is an idication that this watch was made between the late 90’s and 2007. It contains probably one of thos less durable movements with no nickel plating and a reduced number of jewels.


Russian Molnija watch from the 1980’s

  • CCCP is Russian (Cyrillic) for Союз Советских Социалистических Республик — it’s the abbreviation for Soviet Union (Union of Soviet Socialist Republics).

  • the little red symbol with CCCP on top of the letter “K” is the official soviet mark for the certification of quality (see http://en.wikipedia.org/wiki/State_Quality_Mark_of_the_USSR). The symbol with the K on the side and CCCP on top can be seen in the middle of the dial. The Russian word for quality is “качество” thus the letter “K” in the symbol. This CCCP quality stamp means as well that this particular watch was made between 1967 and 1991 (that’s the time period where those symbols where assigned to products by the State Attestation Commission).


Russian Molnija railroad style watch

  • Russian railroad style watches have this “wheel with wings” symbol (flying wheel) on the dial and a train on the back. Note that those are watches with standard movements. They are not more accurate than any other Molnija watch.

A watch that does not have any cyrillic letters on the dial was made for export.

Markings on Molnija watch movements

One or more of the following markings can be found on Molnija movements:

  • “ЧЧЗ” or “Ч2З”. A lot of people will read this as 443 or 423. It’s however not a number. “ЧЧЗ” is an abbreviation for “Челябинский Часовой Завод” and means Chelyabinsk Watch Factory. “Ч2З” is an acronym for the 2nd Moscow Watch Factory (2-й Московский часовой завод). The “2” is actually slightly bigger and sticking out. It is more like “Ч2З“. You are supposed to read the 2 before the other letters even though they are not printed in that order. In other words one should read this as “2ЧЗ”. That is the abbreviation for “2-й часовой завод” (“2nd Watch Factory”) and that is the 2nd Moscow Watch Factory. On older watches you will find decorated factory symbols:
    What looks like 4 and 4 on top of a star with the 3 in side the star is the Chelyabinsk Watch Factory. The symbol that looks like 423 with teeth from a saw on the outside is the second Moscow watch factory. There is as well the Chistopol Watch Factory (Чистопольский часовой завод) and it would as well be abbreviated as ЧЧЗ (443) but that factory did not make any Molnija watches. It produced the Восток (Boctok, Vostok) line of watches. In other words ЧЧЗ (443) in the context of Молния means always Chelyabinsk and never Chistopol.
  • The Chelyabinsk Watch Factory used in the 60’s and later sometimes this symbol of a watch showing 9 o’clock.
  • The amount of jewels (ruby stones bearings, камней). Most Molnija pocket watches have either 15 or 18 jewels. Early Molnija watches had 15 jewels and more recent watches had 18 jewels.
  • A serial number. It seems that this number was frequently reset to some value. It’s not exactly clear what tiggered the reset of the serial number and how it was really used. It is possible that a new 5 year plan, which changed about every 3 years, might have triggered the reset of the number. Communists have this notion of a 5 year plan were they set targets for the next 5 years such as e.g production volume targets. Thus the number was reset every 3-5 years and it might have been just a counter for the amount of units produced within a planing interval.
  • Caliber or movement type. Molnija watches did at the beginning not have a caliber system to identify the movement. Early Molnija movements with 15 jewels have an abbreviation stamp that looks like “4K-6” and stands for “Часы Карманные – 6” which means “Watch Pocket – 6”. The caliber system came up in the early 60th. The pocket watches movements have a diameter of 36mm and the first two digits in the Russian caliber system are equal to the diameter. The other two digits define the type of movement. The Molnija pocket watches were available in the following caliber: 3602=small second and without shock protection, 3603=small second and with shock protection, 3608=central second and without shock protection. “ЧК-6” (ChK-6) is sometimes incorrectly referred to as caliber 3601 by people who think that 3601 was the model before 3602 but there was never a 3601 pocket watch movement. Almost all pocket watches are either “ЧК-6” or 3602 caliber movements.
  • A date code in the form of “year quarter” or “quarter-year” and the year was written with just 2 digits (e.g 3-67 meant third quarter 1967).
  • SU for country of production, Sovjet Union.


15 jewels, 1st quarter 1953, factory code “Ч2З” (Moscow), caliber “ЧК-6”, serial number.
It has a very nice high quality surface finish (Geneva stripes) only found in early molnija models.


15 jewels, 3rd quarter 1952, factory code “ЧЧЗ” (Chelyabinsk), serial number.
It has a very nice high quality surface finish only found in early molnija models.


15 jewels, 3rd quarter 1967, movement 3602, serial number


15 jewels, 3rd quarter 1958, factory code “ЧЧЗ” (Chelyabinsk), serial number


15 jewels, 4th quarter 1958, factory code “ЧЧЗ” (Chelyabinsk), serial number


This is not a Molnija movement. It’s an Iskra movement. Note the “Искра” on the winding gears.
It’s basically the same movement as Molnija but it has 17 jewels. 1st quarter 1956, factory code “Ч2З” (Moscow), serial number.


18 jewels, country SU, movement type 3602, serial number, probably 1980’s or early 1990’s


18 jewels, 9 o’clock symbol from the Chelyabinsk Factory, movement type 3602, serial number


18 jewels (not visible), 2nd quarter 1985, serial number


Serial number, country SU, 9-o’clock symbol for Chelyabinsk watch factory below balance wheel,
3603 movement with shock protection. This is a 3603 movement from the 1990’s.


This is a very rare example of a Molnija watch with central seconds (it would be caliber number 3608, but the 3608 is not stamped onto the movement), you can see the extra wheels that were added to drive the central seconds, 16 jewels, factory code “ЧЧЗ” (Chelyabinsk), serial number. Picture curtsy of http://www.nhtwatches.com/


18 jewels and serial number, no date code but old version of the 3602, probably a movement from the 1970’s.

Finding the age of a Molnija watch

It is of course interesting to find out what the age of a given Molnija pocket watch is. In case of many western watches the serial number can be used to determine the age. This is not the case for the Molnija. It seems they did frequently reset the serial numbers and I have not found a list of number ranges for a given year.

The situation is clear in the cases where we have a date stamp on the movement. As you saw in the above pictures there are cases where the movement has no date stamp. In those cases you can estimate the age from the number of jewels and in general the amount of markings:

  • Molnija pocket watch movements have from 1947 to 1960 normally 15 jewels.
  • Molnija pocket watch movements had from 1965 to 1997 normally 18 jewels. From around 1997 they started to produce cheaper versions with fewer jewels (same basic movement just some jewels replaced by steel or brass parts).
  • Early Molnija pocket movements do normally have date codes and are nicely finshed. Recent movements did no longer have date codes nor had they factory codes.
  • Watches made in the last decade before the closure of the factory (around 1997 and up) had often very rough and unpolished parts with no nickel plating. Those watch movements have a brass like color and a reduced number of ruby stones.

Date codes were no longer used from around the 1990’s. The 1970’s and 1980’s were mixed: Some Molnija movements from the 1970’s and 1980’s had date codes most did not.

Some watches made in the 1990’s and later had a spring loaded mechanism for the removal of the the stem (older watches would have had a screw). To remove the stem you put in “set time position” and then you press the pin pointed to by the arrow in the above picture with a toothpick.
The presence of this mechanism is a clear indication that this particular watch was made after 1990.

There are two versions of the 3602 movement. The early version from the 1960s up-to mid 1970s had different plates holding the cap-stones for escape wheel and balance wheel. This is visible from the dial side of the movement. All recenet movements have two identical small plates where as the old version of the movement has a bigger plate for the balance wheel cap-jewel and a small plate for the escape wheel. There is as well a difference in the shape of the pallet bridge. Molnija watches do not have banking pins for the pallet fork. The pallet bridge itself stops the fork from moving too far and those faces stopping the fork are different. Finally the small winding wheel is held in place by a plate and two small screws in the old version of the 3602 while the new one has one screw that is left threaded.

If your molnija has a logo on the back then this can be used to date the watch to some degree. In the 1980’s and earlier the back of the case was a solid silveroid cast and the inside of the case was then nicely finished on a lathe. In the 1990’s they stamped the logos into standard plain cases. You can clearly see the difference. Both cases shown in the photo have a train logo on the outside. The photo shows the inside of the case back.

Starting in the mid 1990’s cheaper versions of the molnija movements were produced. Those movements had no nickel finish (the movement looks golden) and a number of ruby stone bearings where replaced by simple metal bearings (look at the arrows in the above pictures). There is no indication on the movement as to how many jewels the movement has. If you have a watch with such a movement then it was probably made between 1995 and 2007. It is unclear why they decided to reduce the production cost and the quality of the watches. It might have been an new management team that failed to see the value of the Molnija brand and that lead finally to the closure of the factory in 2007.

Molnija pocket watch cases

US and Swiss pocket watch are often made from precious or precious looking materials such as gold filled copper cases, silver cases or silveroid/silverine (looks exactly like silver but is an alloy made copper, nickerl and zinc, also known as German silver).

Early Molnija cases are all made of brass with a layer of chrome or a nickel-copper alloy on top. Later models have a silverine back cover and a chrome plated brass case or have cases made completely from silverine. The solid silverine cases can very easily be cleaned and polished because you can polish them indefinitely without any other metal comming through. Those solid silverine cases are from the 1980’s and early 1990’s. There are some cases from the 1970’s that had a matte grey looking main case ring and I believe that this ring is made of brass with rhodium plating on top.

The Russian caliber system

The caliber of a watch movement is not referring to the diameter of a movement. It describes the type of movement. The Russian caliber system came up in the early 60th and was used from late 1963 onward. All normal Molnija pocket watch movements have a diameter of 36mm. The first two digits in the caliber system are the diameter (xx in the below table).

Shock protection for a mechanical watch indicates that the delicate pivots that hold the balance wheel are mounted in a spring suspension system. A shock resistant watch is supposed to survive falling from a height of 1 meter onto a horizontal hardwood surface without any damage to the balance wheel staffs.

Most of the Molnija pocket watches are caliber 3602. Shock protection is highly recommended for wrist watches but rarely used for pocket watches especially older models. Pocket watches are more protected against shock if they are properly secured with a chain or some kind of string and carried in a pocket.

A few pocket watch models in the late 80’s and 90’s were caliber 3603. The 1980’s models had a triangular metal piece holding the balance jewel and the late 1990’s models had a star shaped metal piece with a round center hole.

Older Molnija watches made before the introduction of the general Russian caliber system had caliber “ЧК-6” which is functionally similar to 3602. Components of the older “ЧК-6” are however not necessarily interchangeable with 3602 due to minor differences in form and dimension.

The 3603 Molnija movement (shock protection) is not seen very often but it can be easily identified because the regulator has two arms that can be moved and the jewel on the balance cock is held in place by a small metal piece sitting on top of the jewel. The metal piece holding the jewel has in this particular case a triangular shape and this is therefore one of the early 3603 movements:

The photos above show a Molnija from the 80’s with a 3603 movement. You have to be careful when you regulate such a movement. The regulator has 2 degrees of freedom: one arm changes the beat error and the rate at the same time and the other one changes only the rate (=speed or frequency). If you do not have a timegrapher then avoid to touch the arm for “beat error + rate” since there is no way you can get the beat error right without an electronic timegrapher.

A Molnija chronograph pocket watch with caliber 3017 was produced from 1959 until 1970. A chronograph is a watch with a stopwatch function (not to be confused with a chronometer). It was known as Molnija Strela (Стрела, means: arrow) and had a movement with 19 jewels. The 3017 movmement was based on the Swiss Venus Cal.150 movement. It is however a completely different watch and has very little in common with the normal Molnija pocket watches described on this page.

Molnija Strela chronograph pocket watch Cal. 3017 movement, Swiss Venus Cal.150 movement.

Molnija pocket watches made for export

A Molnija pocket watch with the the words English “MADE IN USSR” at the bottom of the dial was produced for export.

Molnija wolves, 3602 movement, 18 jewels, Made in USSR on the dial, plastic dial, solid silverine case. The back of those type of Molnija watches with a theme on the back was always painted with a grey matt paint. The paint wears off over time but this watch is very well preserved and you can still see it. You can as well see a bit of the 9-o’clock symbol from Chelyabinsk Watch Factory under the balance wheel.

Those “export molnija” watches had inside most of the time the same 3602 movements as for the home market. The below watch is special because it’s completely “English”, outside at the bottom of the dial and inside. It’s an interesting watch because it has a 3603 movement (with shock protection for the sensitive balance staffs). You can see that the bearings of the balance wheel look different.

We know that molnija watches made in the last decade before the closure of the factory (year 97 and up) had nice designs on the outside but where often technically poorly done on the inside with rough surfaces, simplifications like no central ruby stone, almost no markings on the movement. In other words the below watch was definitely made before 2000. I think that this watch might be from the early 90’s. The fact that it has a special 3603 movement, when most watches used 3602, suggests that they wanted to produce a watch with good technology inside.

Molnija signs of zodiac, 3603 movement (shock protection), 18 jewels, markings all in English, plastic dial, silverine case

Another example of Molnija watches made for export where the Serkisof watches. Serkisof was an Istanbul-based jeweler, a family business. Serkisof imported those watches from Russia in sufficient numbers to be able to ask for small modifications to the style of the watch. Most of them where sold to the Turkish National Railways. The back of those watches said “Serkisof Demiryolu”. Demiryolu is Turkish and means railway. The Serkisof watches are from the 70’s and early 80’s. The movement is an unmodified 3602 movement with markings in Russian (not English). The Serkisof watches have an extra dust cover (visible when you open the back) and it was either a plain cover or it said “FIRST QUALITY, SERKISOF, GUARANTY” (in English, not Russian, not Turkish) on the dust cover.

Molnija Serkisof, standard 3602 movement, 18 jewels, plastic dial, silverine case

Note that those Molnija Serkisof railroad watches are not the same as american railroad watches. They did not have higher accuracy requirements. Those watches have ordinary Molnija movements.

A number of jewelers sold in the 1980’s Russian Molnija watches with their own logos and brand names. Some Molnija pocket watches (and other Russian watches) were sold under the name “Corsar” in Germany. The Corsar watches had no mentioning of their Russian origin on the outside. Molnija Sekonda watches were mainly sold in Britain. Services is a watch company from Leicester, England, and they distributed watched made by other companies under their “Services” brand name. In Canada and the US Molnija watches were sold under the brand name Marathon. Marathon is a company located in Richmond Hill, Ontario, Canada and they are distributing different watches to this date. Molnija pocket watches were sold under more than a dozened names by jewelers all over the world.


A jeweler in Verona, Italy (Visio S.R.L) imported in 1988 an number of Molnija pocket watches specifically to sell them as “authentic Russian fashion curiosity” with Russian look and feel. Visio S.R.L registered both the brand name KRASNIKOF and the corresponding Russian word (КРАСНИКОВ) as trademarks. Interesting is that the watches had on the dial everything in original cyrillic letters except for the word Krasnikof even though they had as well registered the cyrillic equivalent. The Molnija Krasnikof watches were sold in small brown wooden boxes with the letters “KRASNIKOF” on the box. Visio S.R.L sold those watches only for a few years from 1988 until the early 1990’s.

Rubies or jewels

Ruby is a gemstone that is almost as hard as diamond. It consists of Al2O3 with some chromium (Cr3+) ions in the crystal. The chromium gives it the red color. Ruby does occur naturally but it is not too difficult to produce synthetic rubies. This made ruby an attractive material for durable low friction bearings in watches. Molnija watches have, dependent on the model, between 15 and 18 rubies.

The evolution of the Molnija movement

The Molnija pocket watch started in 1947 with the “ЧК-6” (ChK-6) movement. It had 15 jewels and the only caped jewels were those on the balance.


The “ЧК-6” (ChK-6) movement 15 jewels, the balance jewels are caped.

This movement evolved then in the mid 1950’s into the Iskra movement (“Искра”). It had 17 jewels and both the jewels on the balance and on the escape wheel are caped. The movement has the same nice striped finish (Geneva stripes, Côtes de Genève) as the original “ЧК-6”. This movement was however never used on real Molnija watches. It was sold with a watch called Iskra.



The iskra movement, 17 jewels, both the jewels on the balance and on the escape wheel are caped.

Around 1964 a new movement called 3602 was introduced. It had 18 jewels with caped jewels on the balance and on the escape wheel. It was first used in a watch called “Кристалл”, Kristall (Kristal) or crystal in English. There are actually some Kristall watch movements from 1963 that where early pre-3602 versions. Most bigger wheels and the balance are interchangeable with the final 3602 movements but all the screws holding capped jewels where not standardized yet. That early “prototype” version of the 3602 was not yet called 3602 (no 3602 engraving) and it was clearly more complicated to manufacture than the final 3602.


The first 3602 movement as used in the “Кристалл” watch, 18 jewels, both the jewels on the balance and on the escape wheel are caped. It has still the nice striped finish but the balance cock is already without that finished surface. It says 3602 on the side under the balance.

This 3602 movement was then produced without the nice surface finishing and used from around 1966 on in all the Molnija line of watches. There might have been a few early Molnija models too that used the same movement as the Kristall. The final 3602 movements was optimized for mass production with as many screws of the same size as possible and a less complicated surface finish.

How to open a Molnija pocket watch

Put a white linen sheet or white pillowcase on the table before you take a watch apart. This prevents small parts from bouncing around in case they are accidentally dropped.

All Molnija pocket watches have a “snap-on” case. That is: you need a case knife to open the front and the back. Near the top (where the crown is, at 11 o’clock or at 1 o’clock) should be a small gap between the case ring and the front / back. This is where you can carefully insert a case knife and open it. Don’t apply too much force. It should open easily.


Molnija pocket watch case and crown with stem.

To remove the movement from the case you need to first take out the crown.


Molnija movement

Pull the crown up and then loosen screw 1 a little bit, just a few turns (see below for more details). This will allow you to pull out the crown and stem. Remove the front (crystal with the metal ring around it) and then remove the two case screws 2, 3. The movement will come out towards the front.

Taking out the stem and crown

There is a small clutch wheel that is sliding over the stem in the opposite direction in which you pull the stem. If you remove the stem the wrong way then you might end up in a situation where it becomes difficult or even impossible to put it back without taking the watch apart.

Taking it out:

  1. Pull the crown out into the position where you would normally set the time. Remember how far out it is.
  2. Unscrew the little screw on the back about 3-5 turns and push it in with the screw driver. The stem should now come out easily.

Putting it back in:

  1. Put a tiny drop of oil onto the stem.
  2. Hold the watch face down and insert the stem to the same position that you remembered before.
  3. Tighten the screw gently by 1-2 turns and then move the stem slightly up and down to check if it has snapped-in properly. This little screw controls a nose which needs to go into a groove on the stem.
  4. Tighten the little screw a bit more (gently). Push the stem in all the way once you are sure that the nose controlled by the screw snapped-in properly.
  5. Test it.

Removing the hands of a watch

Normally one needs a special tool to pull the watch hands. However if you just repair watches once in a while then it’s not worth it to buy all kinds of special equipment. To pull out the watch hands with your finger nails is not a good idea as you can easily hurt yourself or bend the watch hands. To use a screw driver does more damage than good.

What works well is a prybar type of watch hands remover:


Pry-bar watch hands remover made out of copper wire

To use this watch hands remover you cut a v-shape out of a piece of paper. You discard the V and slide the remaining paper below the watch hands to protect the dial against scratches. You insert the small prybars at the axis below the hour hand and then you push them both at the same time carefully down. The watch hands will just pop up. You can put a transparent plastic bag on top of the watch hands while you do this. This will prevent the watch hands from flying around when they come off.

To make these pry-bars you take a thick copper wire and you cut 2 pieces off. You bang with a hammer onto the wire ends until they are flat. After that you take a file and you make the ends thin enough such that the can be inserted between dial and hour hand. Finally you use needle nose pliers to bend the ends as shown in the above picture. Dull any edges with fine sand paper.

Brass wire, as used for welding, is even better than copper wire because it is stronger. You can as well make such watch hands removers out of stainless steel bicycle spokes.

Removing and cleaning the dial

It’s not obvious at first how the dial is mounted on the watch. There are 2 small screws on the side of the movement. One between 4 and 5 o’clock and one between 10 and 11 o’clock. Those have to be turned loose a few turns and then the dial can be taken off. Obviously the hands for the hour, minutes and seconds have to be removed first.


There are 2 small screws on the side that need to be loosened to remove the dial

Not all Molnija dials can be cleaned. New dials are sometimes out of plastic and they can be washed with a bit of soap. Older dials are silver coated metal plates painted with a white, semi transparent paint. Those dials can not be cleaned. Any cleaning or washing will normally damage the dial and make things worse. You should as well avoid touching the dial with your fingers as salts and acids on the skin will show up as finger-prints after a while.

Cleaning and polishing watch crystals

Almost all Molnija watches have acrylic crystals (plastic crystals). Plastic crystals were in the 50’s and 60’s considered more modern and they had a real advantage over mineral glass. They are somewhat flexible and they would not easily break. Today the trend has reversed a bit and people prefer glass since it does not scratch as easily. Scratched crystals are a real problem with wrist watches. Crystal scratching is not as much of a problem for pocket watches since they are more protected. I would not suggest to fit a glass crystal into a Molnija. Stay with plastic crystals if you need to replace one. They are good and they are in line with the original Molnija design.

A crystal that appears a bit “foggy” because of tiny scratches can easily be polished. Especially plastic is very easy to polish. You need 1micron diamond polishing paste. Use a basic paste, not one with ammonia and other additives for metal polishing. Just simple 1micron diamond dust in some greasy paste. Put a bit of that polishing paste on a cloth and polish the crystal with that cloth for about 3 minutes. The crystal will become shiny and look like new. Don’t use any motorized polishing methods. Those rotate usually too fast and generate too much heat. High temperatures will cause the plastic surface to melt and the paste will burn into the crystal. Just be patient and polish it by hand.

Cleaning and oiling a watch

Used and old watches can be dirty and the pivot holes (bearings) might contain some metal particles. Such a watch needs to be cleaned if you really want to use it on a regular basis. A small amount of dirt in the watch does not effect the frequency at which the watch is ticking. It affects how strong it is ticking. A watch that is running weak due to friction in the movement may temporarily stop and then it will affect the time. If it is running just weak enough to not cause the pallet fork to do a full swing then the escape wheel might slip once in a while and the watch will run way too fast (e.g off by 30min per day).

There are lots of resources on youtube.com as well as some blogs (e.g http://dcwatches.blogspot.ca/2011/08/russian-molnija-3602-pocket-watch.html) that describe how to take a Molnija apart. I will therefore not cover this part here. I do recommend to get a set of quality screw drivers, good tweezers and it is a good idea to watch a number of Molnija watch repair videos or read some blogs about Molnija pocket watches before you even start.

You will find passionate discussions about the right watch oil. Moebius 9010 is something that a lot of people recommend but I think the whole discussion about oil is really over rated. There are cheaper alternatives that are as good. Watches are normally operated at temperatures between 20’C and 36’C and they run rather slow. Not very tough conditions. Watch oil must however fulfill the following requirements:

  • It must be a thin oil that does not spread.
  • It must not gum-up. Thus it should consist of molecules of similar length only (synthetic oil).
  • It must not be plant based (no canola oil). Plant based oils contain many different molecules and oleic acids that can react with metal.
  • It must not degrade (evaporate or oxidize). Any oil evaporates slowly over time even at room temperature but a small drop should stay for decades. Oil can react with the oxygen in the air and watch oil should not do that easily. Synthetic oils are all very stable and are not expected to oxidize, polymerize or volatilize at room temperature for at least 10 years.

Moebius 9010 is a rather thick oil with a viscosity of 150cSt at 20°C. Look for a synthetic watch oil with a quite high viscosity (a thick oil) but it does not have to be Moebius 9010. The type of oil needs to be seen in the context of a specific watch type. A more robust Molnija watch can accept more tolerances and work with a wider range of oils.

An easy way to apply a small drop of oil is to use a dip style watch oiler. Such an oiler can be made from a thin wire. (It’s described in my Hamilton-992b article). A tiny drop forms at the tip of the wire when you take it out of the oil and then you just touch the part you want to oil with the tip of the wire.


The drawing shows the very thin balance staffs sitting in the caped balance wheel jewels (red) with a thin film of oil (blue). The staffs glide on this thin film of oil amost frication free.

There is no oiling chart for Molnija but a Rolex oiling chart can provide some guidance as to where to put oil (rolex-oiling-chart.jpg). You don’t have to use so many different types of oils for the Molnija. Just use the same oil for all the parts except the escape wheel. It’s important to not apply too much oil. A watch that has too much oil will not work reliably. A watch should look “dry” at first sight.

The Rolex chart suggest to put oil onto the escape wheel. What they really mean is to put a few molecules of a very thin oil onto the ends of the escape wheel teeth. A completely dry escape wheel that has just been cleaned and stripped of any oil can benefit from this but be very careful with the amount. You need extremely small amounts that can not even be seen. The pallet fork “hammers” onto the the escape wheel teeth. Oil has surface tension and too much oil or a too thick oil can “glue” the pallet fork to the escape wheel when it is trying to get away from it. However a tiny amount of very thin oil will usually improve the amplitude. It is enough to apply oil to two teeth and it will slowly distribute to the others. I get good results with Moebius 9000 which has a viscosity of 100cSt at 20°C (a rather thin oil).

The most difficult to oil parts of a mechanical watch are the balance staffs. This is unfortunately as well the most important part. The balance staffs are very thin “needles” at the end of the balance wheel axis. They have typically a diameter of 0.1mm and are barely visible with the naked eye. The balance wheel rubies are caped. That is: they are closed at the end and you have to take the balance wheel out to apply oil. You can not oil this part from outside while the watch is still assembled.

I was very nervous when I took for the first time a balance wheel out of a pocket watch but now it is almost a routine job. It is not difficult. The main thing to remember is: Do not force it! It will go out and back in easily if it is in the right position. When you put it back in you just place it approximately in the right position and then push it gently with a tooth pick until the staffs find the holes in the ruby stones. The wheel will start spinning once it is in the right position. You fasten the screw on the balance cock only once you are sure that everything is working.

A tiny drop of oil needs to be between the balance staff and the rubies. The staffs glide on this film of oil. Too little oil causes too much friction and damages the balance staffs over time. Too much oil will dampen the oscillation of the balance. The watch will become unreliable when there is too much oil or too little oil. The drawing on the right shows a balance staff sitting in the ruby stone with the right amount of oil shown in blue.

It’s enough to clean and oil a watch every 10 years if modern syntetic oils are used.

Molnija pocket watch accuracy

Don’t compare the accuracy of old mechanical movements with modern quartz watches. Those old mechanical watches where made when people would tell the time in increments of 5 minutes.

Molnijas are said to be rated with an accuracy of -15 to +40 seconds a day. I think however that you can tune a Molnija to be much more accurate than that. The precision of a mechanical watch depends very much on the environment it is used in. The good thing about mechanical watches is that you have to wind them every day and you can use that moment when you wind the watch to check the time and set the correct time in case the watch it too far off. It’s a good idea to wind a mechanical watch just once a day around the same time. E.g every morning after getting dressed.

These Molnija watches have Elinvar hairsprings which go a long way in reducing the effect of temperature on the beat rate but to have a perfectly temperature corrected watch one needs to play with the alloy and the geometry of the balance wheel until the whole system of hairspring and balance wheel compensates all temperature effects over a wide range. The Molnija watches are approximately temperature compensated. It is good enough for nomal uses. A communist system does not have competition and the products produced by state owned factories just have to be usable. There is no need to bring things to perfection.

Here is a copy of the papers that came with a Molnija and it states “The average daily rate at the temperature of 20’C +/-0.5’C is -15s to +40s.” I think however that this was more a disclaimer than an accurate specification of the varriation you can expect if from a well tuned watch.


Papers that came with a Molnija watch bought in Belgium in 1993. The text is in Russian, French and Spanish. Click on the image to view all the papers as PDF.


Papers from 1980 with sections in Russian, English, French and German. I have framed the English part in orange as the layout is a bit confusing. Click on the image to view the papers as PDF.

A well maintained and clean Molnija pocket watch can easily be calibrated to your usage pattern and be within 10sec accuracy per day. I have infact one particular Molnija watch that is off less than 10sec per week. Such accuracy is however rare.

To really get a Molnija to keep perfect time you will need to adjust the regulator with the help of a timegrapher. You can ask any professional watch maker to see if he has such a machine and if he can adjust your watch.

If you clean a watch and the watch runs after the cleaning a lot faster then check the hairspring on the balance wheel. There might be a tiny amount of oil or dirt somewhere on the spring. Even if the spring coils do not permanently stick together they might do so temporarily while contracting and expanding. The hairspring should always be totally clean and dry. A similar problem appears when you accidentally magnetize the hairspring coil with a magnetic screw driver. Never get too close to the hairspring with a screw driver.

A watch that is running much too slow despite everything cleaned and oiled might have a loose cannon pinion. The wheel for the minute hand is not permanently attached otherwise one would not be able to set the watch. This cog wheel is called the cannon pinion. The cannon pinion is attached with a friction fit. The friction between the axis and that little wheel has to be much higher than the friction caused by the cog wheels used for setting the time and the force needed to move the hour hand (motion work).

Adjusting the rate of a Molnija

Only a clean and properly lubricated watch can really be accurate. The Molnija has a regulator with a simple lever which you can move left or right. The regulator should be approximately in the middle if everything is right and original parts where used during any repairs.

The problem is that the regulator has no precise scale that allows you to adjust the watch in very small increments and this is were a modern timegrapher can be very helpful. A timegrapher is a machine that listens to the various “click events” that a mechanical watch produces and it times those events.


A Molnija watch in the watch holder of a Timegrapher. The silver piece on the back contains the microphone.

The procedure to regulate a watch is as follows. After any cleaning you put the watch into the Timegrapher and you check that it runs at a steady rate with a good amplitude.

Timegrapher settings:

Expected results:

There is a difference in the behavior of old ChK-6 Molnija movements with 15 jewels and the more recent 18 jewel movements (3602/3603). The different jewel bearing types (caped vs not caped) change the internal friction that a movement experiences. Most Molnija movements are 3602 and you should get in horizontal position an amplitude of about 280° to 350° Anything less means normally that the oil in the watch movement is old and gummy. If the movement has just been serviced and old oil is unlikely to cause any problems then the next most likely reason for a low amplitude is cracked jewels or bent balance staffs and a defect like that is not easy to fix.

Don’t try to adjust the rate with the regulator if the amplitude is too low. It will not keep time consistently. Ensure first that the watch runs with a good amplitude. Note as well that the rate of a mechanical watch has a dependency on the amplitude (the higher the amplitude the faster the watch runs).

The rate difference between vertical position and horizontal position is about 15-25sec/day and this is due to the increased friction on caped jewel bearings in horizontal position which results in a change in amplitude. This may seem like lot of positional dependency but even American railroad pocket watches which brag about being adjusted to all 6 positions do have about 15sec/day difference between vertical position and horizontal position. You can still get your watch to be off less than 10sec/day if you carry it the same way every day. E.g mostly vertical while in your pants during the day and in horizontal position at night. The watch will then run a bit slower during the day, a little faster at night and it will average out. There should be almost no difference in the rate between the different vertical positions (stem up, 3 o’clock up, etc…). If there is a difference then the balance wheel is not true.

The beat error of a watch can be adjusted by turning the hairspring collet with a screw driver (be very careful to not damage or bend the hairspring). The beat error should be tested with a timegrapher but to adjust it already approximately you can use the following rule that is only valid for Molnija watches:
With the jewel on the roller table pointing exactly up the hairspring stud should be at the edge of the left balance arm. Note the roller table and the jewel is in the above photo on the other side of the balance and therefore not visible. Inexperienced hobby watchmakers should avoid to play with the beat error. There is always a risk that you damage the hairspring shape when detaching or re-attaching the hairspring from the balance cock. Moving the hairspring stud by an angle of about 3° changes the beat error by 1ms or if you can imagine a distance better: you are moving the stud by 0.2mm to change the beat error by 1ms. However don’t get too excited about the beat error. A watch can keep time nicely even with a higher beat error.

The beat error is zero if the roller jewel sits in idle position exactly at the mid position of the pallet fork such that the pallet fork pushes the balance wheel left and right with the same force. The distance between the two lines on a timegrapher corresponds to the beat error. The smaller the beat error the closer the lines come together. This assumes that the pallet fork works properly. You can have a single line on the timegrapher and still a beat error. If that is the case then double check the pallet fork. The pallet fork is not pushing with equal force left and right.

Here is how a good Molnija should look like on a Timegrapher.


Timegrapher readings of a Molnija pocket watch.

After initial adjustments you use the watch for about a week. At the end of the week you note the error and calculate by how many seconds per day it should be changed. You open the watch and you move the regulator a bit…. but how much is a bit? Let’s say we have to increase the rate by 17sec a day. There is no way to know by how much you have to move the regulator since the scale on the regulator arm is way to coarse. This is where the Timegrapher is very helpful. You can easily push the regulator back and forth until you get the rate changed by the required amount of seconds on the Timegrapher display. The normal Molnija regulators allow you to adjust the rate from about -4min to +4min per day. You can see how little you have to move the regulator to change the rate by just a few seconds.

Note that a Timegrapher can not see any errors due to a loose cannon pinion. Check the cannon pinion if the Timegrapher shows that everything is perfect but the watch is still off by several minutes per day.

Molnija watches with “precision regulators”

The Russians favour usually straight forward basic technology that just works. In general the Molnija movements are exactly that. There is one exception: Molnija watches with a precision regulator. These regulatores don’t work at all. Many American pocket watches had a swan-neck regulator where you turn a screw and you would know that one turn corresponded e.g to 20 sec. This way you could regulate a watch very precisely even without a timegrapher. The Russians came up with this design:


A failed design: The Russian precision regulator.

You are supposed to turn that strange shaped excentric wheel in the centre and the regulator arm would move. But it does not work because there is way too much friction. It does not glide nicely. This wheel is always stuck somewhere because the outer rim is not round. A regulator is a delicate piece and you are supposed to move it gently and precisely. With that setup you can not do it. Stay away from watches that have this “russian precision regulator”. It is a scam.

Maintenance notes

Watch out: screw length on the bridges

If you take an older ChK-6 movement (15j with a striped surface finish) apart then observe the different screw length. One screw on the barrel bridge is shorter. Any of the other (longer) screws would fit but that short screw sits unfortunately right above the arm which moves the clutch wheel for the change between setting and winding. If you do accidentally use a long screw in that position then you will push out that arm.


short screw, ChK-6 movement

Watch out: screw length on caped jewels

The tiny screws holding the two caps on the main plate of a 3602 can be different. Sometimes they have a different length sometimes they are exactly the same. If they have a different length then the longer one holds the cap below the balance wheel.

Stem for hunter case and open face

The stems for hunter cases have to have a longer groove to allow you to push in the stem a bit in order to open the lid of the case. The cases have then a spring to pushes the crown together with the stem back. If you use such a stem for a hunter case in an open face watch then it will have a lot of slag and feel “loose”. The groove for a normal stem is 1mm wide and the one for the hunter case is 1.5mm wide. Here is what those stems look like:


Top: stem for open face molnija, bottom: stem for hunter case molnija

3602 old and new generation clutch wheel

The clutch wheel in molnija 3602 movements up to the late 1970’s had a wider groove in the clutch wheel (1.15mm wide). The newer generation of molnija movements had a smaller groove (0.8mm wide). The new one will not fit on the old movements and you should not use an old one on a new movement.


Different generations of molnija clutch wheels. Left: old, right new.

Regulator pins of ChK-6 movements

The newer 3602 and 3603 movements have regulator pins that are just two posts with the hairspring in between. The hairspring can simply slide out when you remove it from the balance cock. The older ChK-6 movements are different. They have regulator pins that are closed on top. To open them in order to get the hairspring out one has to turn the outer regulator pin with a screw driver. This causes it to open and you can take the hairspring out. Be careful this is not a procedure for beginners.


The regulator pin that can be turned in order to remove the hairspring. You can see the slot on the regulator pin where you can insert a screw driver in order to turn it.

Case ring height

The cases for the first generation Molnija watches (15j, ChK-6 movement) are 0.4mm slimmer than those for the new 3602. You can’t fit a new 3602 movement into an old case. The back of the case will hit the movement.

Replacement balance staffs for 3602

If you replace a balance staff (not something a beginner should attempt) then watch out for the type of replacement balance staff you buy. There are 2 types. The one for newer balances (from around year 2000) with 3 balance arms has a little ring inside and is slightly heavier. If you use such a staff on an old balance (the one with little weights on the rim) then the watch will run too slow. It is only a bit too slow and you can compensate it with the regulator but the regulator will point a lot to the “+”-side.


Different balance wheel generations and the different balance staffs (axis) for those different generations of the 3602 movement.

You are more likely to find the newer type of balance staff because they were produced last but most of the molnija watches out there require the older balance staff version. Some people use the new staffs on the old balances and start then to remove a significant amount of weight from the rim of the balance and that is really a bad idea because you have just ruined the original balance. It is much better to get the right staff and then everything will run properly without any damages to the balance wheel.

All good but amplitude too low

It can be a lot of detective work to find the cause of a low amplitude problem. If you have a watch that is not running well then I would recommend to take out the balance and check how the pallet fork moves. Wind the watch a bit and then move the arm of the pallet fork slowly to the other side. After you have moved it about 1/4 of the way it should suddenly accelerate and shoot off to the other side. It should land on the other side with a “bang” (click). If this is not the case then the problem is somewhere in the drive tain, or the pallet fork itself. If the pallet fork was shooting off as expected then the problem is related to the balance.

Some watches run weak even after everything was cleaned. Here are some ideas:

  • Broken or cracked jewels. Check for chipped ruby stones or stones that have a hair line crack that goes towards the center where the hole is.
  • A bent balance arm is pressing too much onto the ends of the balance staffs. To test for this condition: take a screw driver and pry the the balance cock a bit up. Just a tiny bit, don’t slip. See if the balance runs stronger while you pry it up.
  • Too much oil on: balance fork, balance bearings
  • Too little oil on the escape wheel or the balance bearings
  • Hairspring sagging and touching the balance arms or hairspring generally out of shape (ruined by a previous repair attempts).
  • Balance scratching occasionally on the pallet bridge (bent balance wheel or damaged staff)
  • Seconds hand scratching somewhere
  • Missing oil on setting wheels.
  • Are you sure you cleaned all the jewel holes properly?
  • Pallet bridge bent and pressing too hard onto the palet fork.

By far the most common problem is a hairspring that is out of shape. Especially the end-curve is often twisted. This is usually the result of poor repair work. Many hobby watchmakers don’t have timegraphers to easily diagnose poor repair work. They are often not aware that their way of handling the hairspring twists the spring a bit. After two or three services of the same watch the problem becomes finally so bad that the hairspring is touching somewhere. The watch runs often at a very low amplitude but even if it still has a good amplitude it will no longer keep time in different positions. Such watches are frequently sold as “working and serviced” but they are no longer proper time keepers. It requires a steady hand and a lot patience with many small iterations until such a messed-up hairspring is back in shape.

Here are two timing machine readings from the same watch. In the first reading you see how a hairspring with a twisted end-curve is scratching somewhere ever so slightly. Note that the watch is actually running at a good amplitude (325°) despite the scratching (it’s just touching a bit, if the hairspring end-curve would be twisted even more then the amplitude would go down significantly). This is a very typical fault frequently found on old watches that had been serviced by many people many times over. The dots on the timegrapher are all over the place but without a timegrapher it could easily be taken as a good watch at first glance because it is running strong. However make no mistake. This watch would be a terrible time keeper.

Below is then the same watch after some careful adjustments of the hairspring. You see two parallel lines on the timegrapher. This watch will now keep time.


Timing machine readings: hairspring with a twisted end-curve and the same watch after the hairspring was adjusted.

Tightening the cannon pinion

You should avoid to take off the cannon pinion when you clean and oil a watch unless you suspect there is a problem. This is a small cog wheel that sits on the axis in the center of your watch and the minutes hand is attached to it.


The cannon pinion is a cog wheel that is sitting with a friction fit on the axis

The cannon pinion is attached with a friction fit. If you take it off, oil it and put it back on then you will reduce the amount of friction and the watch may stop working.

A watch that is several minutes slow per day and the amount of minutes change in an erratic way from day to day may have a loose cannon pinion. A typical example would be a watch that is one day 5 minutes slow and the next day 9 minutes slow. If the cannon pinion is very loose then you will see that the watch is ticking, the seconds hand is moving but the minutes hand does not move.

Normally you need special pliers to tighten the cannon pinion. If you are however an occasional “weekend watchmaker” then it’s a problem to buy all those tools. Here is a cannon pinion tightening tool that works well and you can build it yourself. You need a small steel metal sheet, 0.6mm to 0.8mm thick and you cut a slot into it using an iron saw with a fine blade. This cannon pinion tightener can be seen in the photos below. You slide the cannon pinion into that slot and you tap with a hammer gently onto the top of the cannon pinion tightener such that the middle of cannon pinion is compressed. When you think that you did compress it enough then you turn the cannon pinion by 90 degree and you compress it again. Be careful to not make it too tight. You can mark one tooth of the canon pinion with a felt tip marker such that you know which sides you have compressed. This way you can test it in the watch and put it back into the cannon pinion tightener with the same orientation in case it is still too lose.


The self made cannon pinion tightener


You tap with a small hammer on top of the self made cannon pinion tightener to tigthen the cannon pinion. Don’t hit too hard!

Molnija cases and designs

There are just too many different designs to list them all. You may have noticed that there are no pictures of hunter cases on this page. There are many Molnija hunter pocket watches with interesting case designs. I just don’t like them. The cover of a hunter watch is in my opinion pointless. It does not offer any protection. The real dangers for a pocket watch are mechanical shock, water and dust. The hunter case does not protect against any of them. It might be useful if you have some other things in the same pocket such as a pocket knife or keys but if you care about your watch then you reserve an entire pocket for it. It’s safer.

Most open face Molnija pocket watches have a similar dial designs. White or silver dial, black numbers maybe some red. There are however some watches that stand out as completely different and those are often home made versions.


Molnija PILOT. The movement is a 3602 from 1984 but the dial is clearly new. The dial is made out of a painted thin metal base sheet. This is basically how most dials are made today for any kind of watch. I do really like the look and the design of the watch.



This one is essentially the same as the Molnija PILOT but in a smaller case and it does actually say Molnija on the dial itself. The dial is again made like any modern watch dial (painted metal). They did certainly not come out of the main Molnija production line. In any case, a very nice watch.

The Molnija brand is still alive and there is still a Molnija company. A few people have carried on making “Molnija watches” even after the factory closed. They do watch designs and they outsource the actual production of dials to other companies. This is then combined with movements and cases from old watches or “new old stock” parts. People working at the Molnija factory took boxes of parts home when the factory closed. Some of these parts are still around and they show up in new watches. Each of those watches is slightly different since they are not production line watches. They are however very nice watches and they are truly unique.



Molnija air-force reconnaissance. The movement is a 3602 from the 1980s. Chorme plated brass case. At the bottom of the dial it says in dark red letters “военно-воздушная разведка” which means air-force reconnaissance (espionage from the air).



This Molnija watch from the 1970s is somewhat unusual because of it’s dial size and the rather small crown. It hurts almost when you try to wind the watch because the crown is so small. Smaller Molnija watches have normally a 39mm dial and the bigger ones have a 43mm dial. This watch has a 41mm dial and only very few watches of this size where made. All pre 1970s watches have a 39mm dial and the bigger watch dials came later. I believe that this 41mm dial was a somewhat experimental design before they settled with the nice big solid silveroid cases and the 43mm dial. It shows that the transition from the old Molnija design to the new was done in steps and they tried different options before they found a good design.

The early open face versions of the Molnija watches had just patterns or strips on the back and the case was made out of chrome plated brass.

In the late 1970s open face versions of the Molnija watches with cases made out of silveroid had back covers decorated with some kind of theme were produced. There are a lot of different themes to commemorate events and there were some generic ones.
The more common ones are shown below:

  • Animal themes:
    Russian wolves, Russian bears and horses.

  • Sailing ship:

    This ship on the pocket watch is probably the Russian frigate Oryol that served in the Russian navy from 1667 to 1670.
  • Train, steam locomotive:

    The steam locomotive with its tender on this Molnija pocket watch is probably the soviet passenger steam locomotive P36 (П36). The P36 was built in the 1950’s at the Kolomna Locomotive Works. It is the last line of steam locomotive built in Russia.
  • Tale of the Ural:

    The watch design is based on a monument by Vitaly Semenovich Zaykov (Виталий Семенович Зайков). It was erected in 1967 and can be found to this date near the main train station in Chelyabinsk. The mighty giant is 12m high and refers to the Tale of the Ural mountains, written by Pavel Bazhov. The sentence on the pocket watch back “сказ об урале” means Tale of the Ural. This sentence is as well found on the stone statue on the side. The sentence below the front of the stone statue is “Урал! Опорный край державы, её добытчик и кузнец” which means “Ural! The State’s backbone, its supporter and blacksmith”. Here is a screen-shot from google maps and a photo of the actual statue:


  • Firetruck, tractor and motorcycle: These are less common themes. The motorcycle is mostly found on Molnija quartz watches.

The Chelyabinsk watch factory

The Chelyabinsk watch factory was the main manufacturer of Molnija pocket watches. The factory produced watches for civilian use but it was as well a supplier of the Russian Ministry of defense. One of its products for the military was the aircraft cockpit clock АЧС-1 (AChS-1).

You can find the address of the factory on old warranty certificates that came with some of the watches issued in the 1970s:

Molnija Factory address

The plant was located in the city center of Chelyabinsk in a four-storey building, originally designed for the urban public library. South of the former factory building is a nice administration building with white columns. Here is address of the factory written such that you can copy/paste it into google maps:

This is a screen-shot of google maps showing the factory building and the admin building:
Molnija Factory

Below is a photo of the original factory building and the admin building would be to the right:
Molnija Factory Building
The factory building was renovated after the closure of the factory in 2007. It got a new black/grey glass facade and was converted into a shopping mall. What you find today in google street view is this:
Former Molnija factory, admin building in the front, factory (now shopping center) in the back
You see the admin building in front and the glass building in the back is the shopping center which would have been the former factory building. A google street-view screen-shot from the other side shows then only the shopping center (former factory): Former Molnija factory, now shopping center

Here are some historic photos of the Chelyabinsk watch factory. You can click on the individual images to see them bigger. Much of the assembly of the watches was done by hand. The Chelyabinsk watch factory provided work for many people in the city:

The admin building in the 1970s
construction work to convert the factory into a shopping mall
assembly of the watches by workers
a worker and some of the watches she made

From left to right: the admin building in the 1960s or 1970s, the conversion of the factory building into a shopping mall, workers assembling the watches, a worker and some of the Molnija pocket watches she just made; this photo has a note on the back which says: production unit 9, Ivanova Lusya Dmitrievna, 1980, city of Chelyabinsk.

Slava plant in Besançon

Besançon, France had a Russian Slava factory where they assembled watches based on Russian movements and parts. The factory was called Slava and they had a big Slava sign on the building but the assembled watches kept their Russian brands (Slava, Raketa, Wostok, Poljot, Zaria, Molnija, …). Molnija movements were imported to make pocket watches. The following are pages from a catalog and it’s a detailed listing of the different components of a Molnija 3602 movement:

Slava Molnija catalog, front
Slava Molnija catalog, back

See as well: http://www.montres-russes.org/t6381-fiches-techniques-de-mecanismes-sovietiques

Buying a Molnija on ebay

Some people list watches as “excellent condition, working” just after winding them and checking for a moment that they are ticking. That may be an acceptable test for a quartz watch but mechanical watches are complicated devices and can’t be checked like that.

If you are looking for a watch that is actually working and really usable as a watch then read description carefully to see if the seller makes any claims with regards to the accuracy of the watch. Check the description of the seller to see if the watch was serviced by a watchmaker. My experience with ebay is that Molnija watches that have not been serviced properly are normally barely functional even if the description says “running” or “working”.

Buy a Molnija in Guido’s own watch shop

I love pocket watches but I noticed during the many years that I haven been collecting watches that it is really hard to buy a good vintage watch that really works. To fill this need I started my very own pocket watch shop and I am selling only watches that are really good. I am selling vintage watches that can really be used as reliable timepieces.

Have a look!
http://watchshop.tuxgraphics.org

Buying a Molnija at antiques stores or flea markets

Here are a few suggestions for things that you can check when you buy the watch in person.

  • Inspect the watch visually for damage.
  • Wind it.
  • Listen to it.

A good watch has a sharp metallic sound and it does not change when you hold it in a different position. A dull click-click or a scratching sound is an indication of a severe mechanical problem.

Here is how a good molnija pocket watch sounds:

DIY pocket watches based on Molnija parts

Both the swiss movement manufacturer Cortebert and Unitas, another famous movement manufacturer, were part Ebauches S.A. Ebauches S.A was a holding for different movement manufacturers and it became later ETA. Those companies under Ebauches S.A focused mainly on movements which other companies would then use to make brand name watches. Those where the “engine manufacturers” of the watch industry and the raw movements are called ebauches. An ebauche is a working movement but it is a blank without serial number or any detailed markings. Often it is not even lubricated yet. The expectation is that the company that installs it in a watch will finish the movement, oil it and regulate it.

Because of this friendly relation between Cortebert and Unitas there is a Unitas movement which is pretty similar to the Cortebert 616 in terms of dimensions and general layout. It is the Unitas 6497. Some of the screws are even in exactly the same positions. The Molnija 3602 is derived from the Cortebert movement. Unitas 6497 movements are one of the most successful movements ever made and have been in continuous production since 1950. The Unitas 6497 has some of the features of the Molnija movement but it has as well an Incabloc shock protection which makes it even better and more robust.

It is possible to fit a Unitas 6497 into a Molnija case:

  • The distance between the seconds hand and the center is almost the same (there is a difference of 0.25mm and that is neglectable). The dial feet are however in a different position but it is possible to install new dial feet on an old dial. Here is a drawing with the exact measurements of the 6497: 6497-dial-measurements.jpg, 106483 bytes.
  • The vertical position of the stem is exactly the same.
  • The stem itself is different but the thread is the same. In other words you can use Molnija crowns on Unitas 6497 stems.
  • The whole in the tube on the Molnija case has to be enlarged to 1.5mm in order for a Unitas 6497 stems to fit. It is a simple matter of enlarging it with a 1.5mm drill and you are only taking away 0.02mm.
  • Both Unitas 6497 and Molnija 3602 have rougly the same size. You have to make the diameter of the Molnija case 0.6mm bigger and then a Unitas 6497 will fit.
  • Most movements you buy today are meant to be installed in wrist watches and they don’t have the same case screws as pocket watches. Case screws are as well not standardized and original Unitas 6497 (running at 18000 bph) case screws will e.g not fit into the Chinese ETA-6497-2 clone (called ST36, running at 21600 bph). However Molnija 3602 main plate screws (not case screws) or ChK-6 case screws can be used as case screws for ST36 movements.
  • You have to get new watch hands that fit unitas. Molnija hands will not work.

It is nice that a Unitas 6497 can be fit into a Molnija case because sometimes it is very hard to repair an old and badly treated 3602 movement. A badly damaged movement can just be beyond repair. You can bring new life to such a watch by installing a Unitas 6497 or the popular Chinese Seagull ST36. The ST36 is by the way an excellent movement. The Chinese made a very good copy of the ETA-6497-2 and improved it esthetically (an original Unitas 6497 has more “square” bridges). ETA-6497-1 is a movement compatible with the original Unitas 6497 and runs at 18000 bph. ETA-6497-2 is a newer version designed after ETA bought Unitas and it runs at 21600 bph. Most parts are not interchangeable between ETA-6497-2 and the original Unitas 6497. Most parts of the Chinese ST36 are interchangeable with the same parts from the ETA-6497-2. Watch out if buy individual parts for a 6497 movement. A lot of people seem to be unaware of those different movements and they might e.g sell you a main spring barrel for ETA-6497-2 calling it a Units 6497 barrel. A main spring barrel for ETA-6497-2 has however much smaller teeth than the original Unitas 6497 barrel. You can easily see the difference between those movements. The 21600 bph movement has a pallet bridge (under the balance) with 2 screws and the 18000 bph version has one screw on the pallet bridge.

Here is an example of such a watch. I did not reuse the old Molnija dial in this case.

Molnija case from 1970 with a new Chinese Seagull ST36 movement, Unitas 6497 clone. The old case gives the watch a nice vintage look, a feature that I really like.

ps: Never convert a vintage pocket watch into a wrist watch. That’s a crime ;-). Keep those beautiful pocket watches alive. These days one can find a lot of crappy pocket watches but high quality pocket watches with a good movement and a solid case are becoming increasingly rare.

How to fix molnija dials

Almost all of the larger open face molnija watches have PVC dials. There is nothing wrong with PVC. It is quite durable, the problem are the dial feet. Plastic is soft and when squeezed by tight dial screws the feet mold themselves into the holes and they are really stuck there. Never tighten the dial screws too much!

In any case there are a lot of molnija watches out there that lost their dial feet when somebody tried to service the watch. Even worse there are “watchmakers” who use then glue to attach the dial directly to the movement. That is the most idiotic thing you can do. It does not only degrade the dial further, it damages as well the surface of the movement and it is very hard to take the dial off without further damage.

The right thing to do in this case is to attach metal dial feet to the plastic dial. It is possible to solder dial feet onto a thin copper foil and then glue the foil to the dial. This way you have now a permanent solution that does not easily break and the dial can still be attached and removed from the movement.


Plastic dial with metal dial feet on thin copper foils. It makes the dial only 0.2-0.3mm thicker. On this particular dial you can as well see significant damage from previous repairs were the dial was glued directly to the movement.

The problem is that it is sometimes not possible to add dial feet. It works only on molnija watches with a sunken sub-dial for the seconds hand. Molnija plastic dials are 1mm tick and that is about the maximum thickness you can have on a 3602 movement to attach reliably the hand for the seconds. If the sub-dial for the seconds is receded then you have still enough space to add metal dial feet on copper foils. They add about 0.2-0.3mm. There are however some molnija watches with plastic dials which do not have sunken sub-dials. The whole dial is flat and there is no way to fix those dials properly because there is no space left to do anything. You can try to scratch plastic off the back of the dial to add dial feet without pushing the dial up but that is difficult too. Some watchmakers use thin double sided tape to glue the dial to the movement and that is removable without too much damage but I don’t like that idea and such a “taped” dial can easily loosen over time.

One solution for such a dial that can not be repaired is a new dial. Here is how to make one. You can as well use this method to make your own custom dial.

DIY watch dials

The best base material for making dials is a very thin metal sheet. I recommend 0.3mm tin. You can use the bottom of a tin box for coffee, cookies, baby formula, … check your grocery store. Just make sure the tin is not painted. Tin is iron galvanized with tin (Sn) and it can be very thin but it is still quite strong.

Get a piece of copper wire with a diameter of 1mm, make a fresh straight cut on one end and solder it to the tin sheet. Molnija dial feet need to be 27mm apart and a line between the dial feet passes 0.5mm below the center of the dial. Cut the newly made dial feet to the right length (straight cut, don’t use a cutter that produces sharp pointed ends).

0.3mm tin sheets are so thin that you can cut a nice round circle out of them with scissors for cutting finger nails. This dulls the scissors a little bit but you can cut quite a few dials with one pair of scissors. The dial diameter for large molnija dials is about 43mm.

It is now time to print the new dial. I print the dial on good quality paper. Some people print on photo paper but I think a good standard paper is better because it can be soaked with paint and it becomes therefore more durable.

Files to print the dial:

I print the dial pattern with a laser printer on high quality 100g/m2 A4 paper (or US letter, 8 1/2×11 inch, 24 lb paper, [~90g/m2]) such as Xerox Xprint paper. I use the old Gimp-1.2 to print the file because it has a good print dialog where you can position the image and scale it precisely. You have to experiment with the scaling. Dependent on your printer and the paper size (A4 or Letter) you will end up with slightly different scaling factors.

I spray the front of the printed dial with a clear coat. I cover it right after spraying with a lid from a jar such that the solvents concentration from the paint stays high and the paint dries very slowly. It helps as well to spray in a cold area as this will again cause the spray to dry more slowly. All this soaks the paper in paint and causes the paper and plastify. Once the front is dry I turn the paper over and I paint the back with a white oil based paint. The paper soaked with the clear coat paint on the front becomes somewhat transparent and for the dial to remain white I paint the back with a white paint. Let the white paint again dry very slowly such that it can penetrate the paper from the back.

Cut the printed dial out and glue it to the metal dial base. Lepage (Henkel) “100% glue” works well and is solvent/oil resistant. The final dial is very strong, durable and only 0.45mm thick. It gives you ample space to install the watch hands properly.

Here are a few photos of the whole DIY dial making process.

Artistic and creative watch hands

Molnija watches are normally reasonably priced and that makes them affordable for some home made watch designs. You would not risk to ruin a 1000$ watch but you might want to try a few new things on a 100$ watch.

New watch movements come usually with some default hands for the seconds and the minutes. Those are plain brass watch hands, not painted or treated in any way. They are ideal for some home made designs.

I am going to make a hand for the seconds that looks like an airplane. A very nice feature for a pilot style military watch. For this I take piece of 2mm thick cardboard and punch a hole into it with a needle. This cardboard is going to be my “work bench” for soldering and the hole will hold the axis of the seconds hand such that the hand is flat on that cardboard. It can even be secured with a bit of tape. This allows me to solder two 0.15mm thick brass pieces across such that they look like the wing and the tails of an airplane. It is important that the final hands are as thin as possible otherwise they will collide with the hour hand inside the watch. You don’t need a special soldering iron for this but you need a good SMD solder flux and you just use tiny amounts of solder wire with lots of SMD solder flux. This will allow you to create very thin films of solder. I paint the seconds in black and one side of the “wing” in red.


A watch hand for the seconds that looks like an airplane.

You can build other things besides seconds that look like airplanes. A propeller comes e.g to mind when you think about pilot style watches. Just solder a very thin wire bent at an angle of 120° to an existing seconds hand and you have a propeller with 3 arms. The wire can be squeezed flat with pliers after it was bent.

New Molnija watches made after 2007

There are basically two kinds of “new Molnija” watches:

  • New watches, old stock: A number employees took unused parts, movements and cases home at the time of the closure of the factory. Those where assembled into Molnija watches or Molnija like watches and often sold on ebay.
  • New watches made by the current owners of the Molnija brand. A small group of people continued after the closure of the factory. They had their offices in the old administrative building and they are trying to revive the Molnija brand with new designs.

Here is an example of such a new Molnija watch. It was made around 2014 and I bought it in 2016. The design is inspired by the AChS-1 (АЧС-1) Military Cockpit Clock as used in Russian MIG fighter jets. The AChS-1 was made approximately between 1960 and 1990 by the Chelyabinsk watch factory for the Russian military. This new Molnija АЧС-1 pocket watch is based on a Japanese Miyota 6S21 quartz movement. I was told that all other parts are made partially in China and Russia. It was more a prototype to see if people would buy it. They made as well a similar wrist watch and as of 2018 you can still get the wrist watch but this particular pocket watch seems to be discontinued. This pocket watch is a chronograph (watch + stopwatch).



The wrist watch version of the АЧС-1 looks like this:



The AChS-1 cockpit clock is a clock plus a timer to measure e.g the flight time. It is probably based on the swiss Jaeger cockpit clock made in the 1940’s by Jaeger LeCoultre for the Russian military. It is a purely analog wind-up clock. The electrical connections on the back are for a heating element to stabilize temperatures and prevent ice buildup. It’s quite a large clock and the luminous dial does not seem to be radioactive. The crystal measures 7.4mm in diameter (just under 3 inch). I don’t know which kinds of air planes had this cockpit clock but the most well known is probably the Mikoyan MIG-29 fighter jet (МиГ-29, https://en.wikipedia.org/wiki/Mikoyan_MiG-29) and models of the MIG-29 made in the 1980s had this clock in the cockpit. It was located at the bottom just behind the center control stick.

Ideas, your experiences and suggestions

Write me if you have some thoughts about Molnija pocket watches. You can contact me at: guidosocher@fastmail.fm

Note: Don’t ask me about the value of a watch. I don’t estimate prices. The value of a watch is all in the head of watch owners and future owners. The value is not in the watch itself. With the exception of some low-end poor quality designs there is no difference between a 100$ watch and a 1000$ watch. It’s all in the name of the brand, the condition of the watch and mostly in your head or the imagination of other collectors. Yes, there are gold plated watches and chrome plated watches and watches with blue screws and watches with decorations on the case and watches without those…. Do you think there is a difference in the material value (gold vs chrome etc…)? That difference in raw materials is negligible. The difference is none. It’s all in your head. It’s like art. You decide what the value is based on your preferences.

Many people understand old cars and the complexity that goes into the price of an antique car better than antique watches. Old watches are in many ways similar to old cars. What’s the value of an old car? It depends in its condition and the brand. You can buy rusted antique cars for very little money but to get an old car that is in good condition and works like a new car is very expensive. The same goes for the service. To service an antique car can be way more expensive than the equivalent procedure for a new car. It’s out of production, good spare parts are difficult to get and to find a skilled mechanic that can service such a rare car without damaging it can be difficult and expensive. It’s exactly the same for antique watches.

There is a clearly quantifiable cost related to the restoration of an antique watch. It is simply the amount of hours and the cost per hour to do the work. It takes me usually 1/2 a day to clean a movement, replace any worn out parts, adjust and regulate it, wash and polish the case. Most antique watches have messed-up hairspring end-curves from previous services gone wrong. To carefully adjust that end-curve such that it will run like a new watch can take alone more than an hour.

Links


© Guido Socher, email: guidosocher@fastmail.fm


еще про часы – весь проект с исходником ну и что 12 лет назад сделано..

Evan Quirk
NavigationHomeExport Google Reader Shared Items to Delicious Style HTML Bookmark FileNTP Synced Nixie Tube ClockXfire::Aim Gateway (Pidgin Perl Plugin)G4L Master Boot Record Backup (Imaging System)BSI Installer (BSI Silent Installer)ShadowCopy (Samba with rsnapshot backups)Blackout (Iphone UI Theme)Home‎ > ‎ NTP Synced Nixie Tube Clock posted Jun 4, 2009, 1:38 PM by Evan Blair Quirk   [ updated Jun 5, 2009, 4:02 PM ] A clock constructed using vintage nixie display tubes that is able to fetch the current time from the internet via NTP. Nixie tubes are gas filled display tubes that were popular in early electronic devices. They have a single anode, and a number of cathodes which are connected to the numerals contained in the tube. When a high voltage source is connected to the anode and one of the cathodes is grounded, the corresponding numeral is surrounded by an orange glow. They are currently popular among electronics hobbyists because of their unique looks. NTP, the Network Time Protocol, is a protocol for computers and other networked devices to negotiate with a server to retrieve the current UTC time.

Videos: Clock Digit Crossfading, New Date Displayhttps://www.youtube.com/embed/aH-_WG5Hy8o?rel=0&wmode=opaque
Clock Startinghttps://www.youtube.com/embed/6kzDlCZGi_o?rel=0&wmode=opaque
Clock in 24 Hour Mode, Old Display Date Featurehttps://www.youtube.com/embed/2FaOlyIrIT4?rel=0&wmode=opaque
Clock Cathode Poisoning Preventionhttps://www.youtube.com/embed/8dKafjMmxLA?rel=0&wmode=opaque
Design Considerations: Constructing a clock using nixie tubes is nothing new. It has been done countless times, to the point where it is almost considered a rite of passage for an amateurs in electronics. I was interested in building a nixie clock, but I wanted to do something different, something you couldn’t find in a kit. Eventually I decided on building a nixie clock that would be able to fetch the time automatically. I decided to do this via NTP. This led to the development of several design considerations: Hardware and Software Components: By deciding to use NTP for time synchronization, I decided that software would be a significant design aspect. The software would have to have knowledge of TCP/IP protocols, mainly UDP for NTP synchronization. The software would also have to convert the UTC time into format suitable for output. Hardware would have to include all components needed for display as well as those for network communication. Having both hardware and software components would also help me to learn as much as I could from the project. Open Source: Because of the rapidly increasing scale of this project I decided I would use existing open source code and design wherever possible. In addition, all code would be released under an open source license so that others could learn from and extend it. Hardware Simplicity: Wherever possible, I would attempt to make my circuit board as simple as possible. This was primarily because this project would be my first attempt at working with and producing my own circuit boards. As such, I would be making a single sided circuit board with all through hole components. In addition, in any case possible, software simplicity was to be sacrificed for hardware simplicity. I didn’t want to have a board full of jumpers. Traces on the circuit board would be placed where they fit, and any undesirable connections would be fixed in software. Modularity: As my first electronics design project, I was guaranteed to have problems on this project. I would build each major section of the hardware separate. This way, if there was an error on one of the boards I wouldn’t have to remake all of them. Design: Hardware: Tuxgraphics NTP Clock: While researching I found an NTP synced clock on tuxgraphics.org. It turned out to be a perfect base for my clock, and the entire project was open source. It utilized an Atmel ATMEGA168 microcontroller to communicate over SPI to an ENC28J60 ethernet chip. I would be able to reuse the network code and just write a new display component suitable for driving the nixies. Overall Design: ENC28J60 and Support Hardware: Ethernet Schematic The configuration for the ENC28J60 is fairly standard, as per the tuxgraphics configuration. The ENC28J60 requires a 3.3V Vcc so both the microcontroller and it share a 3.3V supply. Communication with the microcontroller is done over the four pin SPI interface. The ENC28J60 is also linked to the INT0 pin of the microcontroller for external interupts. Additionally, the ENC28J60 provides the clock for the ATMEGA168. The ENC28J60 is clocked at 25mhz and an internal frequency divider divides it into a 12.5mhz clock. This is slightly out of spec for the ATMEGA168 as it is specified to be capable of 0-10MHz @ 2.7-4.5V and 0-20MHz @ 4.5-5.5V. However, in practice there seems to be no problems with running at this slightly higher clock. A “Magjack” is used to supply the required magnetics and leds in a form integrated into an ethernet jack. The microcontroller and ethernet support hardware occupy one of the three major circuit boards Nixie Tubes: I decided on IN-14 nixie tubes, manufactured in the former Soviet Union. They were chosen for their medium size and affordable price at approximately $3 + shipping per tube. A translated datasheet indicated that they required a 170 volt power supply and comsumed 2.5mA of current. I would use a total of six tubes, two for hours, two for minutes, and two for seconds. I decided to order a professionally made circuit board from nixieclocks.de to mount the nixie tubes on as I was not sure how fine a level of detail I would be able to achieve by making my own. This is the second major board. High Voltage Power Supply: I based my HV power supply off a common design for a switch-mode boost converter. It is constructed around a 555 configurable oscillator. Switch-mode power supplies are notoriously difficult to implement and as such I borrowed the circuit design from a kit sold from ledsales.com.au. Fully explaining the operating principles of switch-mode power supplies is outside the scope of this project, but wikipedia has an informative article on the subject.The high voltage power supply occupies the last major circuit board along with the anode control hardware described in the next section. Nixie Tube Control Hardware: Although the microcontroller is responsible for controlling the six nixie tubes in my project, it cannot directly interface with them. It operates at 3.3V and the nixie tubes require a voltage of 170V. As such, an intermediary would be required between the microcontroller and the tubes to direct the flow of high voltage. The most common configuration is an intermediary controller on the cathodes, either through discrete components (transistors, resistors) or via the 74141 IC. This is known as a direct drive display. In my case, I would be using controllers on both the anode and cathodes. This configuration is used to facilitate a process called multiplexing. In a multiplexed display, the tubes are never actually all on at the same time. Instead, they are lit up in rapid succession. This happens at a frequency higher then the refresh rate of the human eye so the display simply appears to be continuous. Multiplexing is advantageous because it extends a tube’s lifespan and requires less pins then a direct drive configuration. The multiplex configuration I chose is called a 2×3 multiplex. This means that two tubes are on at a time and that there are three sets of two tubes. I decided to use the 74141 IC for controlling the nixie tube cathodes. The 74141 is a BCD (binary coded decimal) decoder. This means that it takes a nibble (half a byte or four bits) as input, decodes its binary equivalent, and switches the corresponding cathode connection to ground. For my 2×3 multiplex I would need two 74141 ICs, one for each of the two tubes that would be on at the same time. The cathodes of the six tubes are split into two groups, with each groups cathodes being commonly connected. Anodes from each group is paired such that when one anode pair is connected to high voltage, one tube from each cathode group will be controlled by a 74141. When it came time to do board layout, I ran across a slight problem laying traces for the 74141 ICs. The nixie tube board cathode connections were in sequential order while the 74141 ICs cathode connections were scrambled. Rather then run a bunch of jumpers to order the 74141 connections I decided to connect them where they made sense. I would do output adjustments in software. For example, if I wanted to display a 0, I would have to send the 74141 a binary 2.

4Anode Control Hardware Switching the anode pair was to be done with discrete components as there is no 74141 equivalent for controlling high voltage anode connections. Instead PNP and NPN high voltage transistors would control the flow from the 170V high voltage power supply. The shown 22k resistor is reduced from the usual 33k resistor used in other designs because the microcontroller supply is 3.3V instead of the typical 5V. Schematic: Software Keeping Time: Keeping track of time is a relatively simple matter. In this case, it is kept in a 32-bit variable in unix time. Unix time means that the variable describes the number of seconds enlapsed from midnight UTC on January 1, 1970. We’ll only be syncing our time variable with an NTP server every hour, so we still need to increment the time variable locally. This is done by generating a timer interrupt every second, during which the time variable is incremented. Main Function Design: Despite being simplified, the following pseudo-code main function closely follows the actual flow of the nixie clock software. main() {
initialize();
while(1) {
recieve_packet();
if no packet {
if time not set { request_ntp(); }
time_conversions();
display( hourh, minl , anode_pair_1 );
display( hourl, sech , anode_pair_2 );
display( minh, secl , anode_pair_3 );
if minutes = 59 { request_ntp(); }
}
else { interpret_packet(); }
}
}
Code Explaination: The first pseudo-function, initialize(); , contains a number of operations that essentially initialize the clock. First, the microprocessor’s clock source is set to the ENC28J60. Over SPI the ENC28J60 is instructed to increase its clock output to 12.5mhz. Next, stored options are read from an eeprom. Then the ethernet layer is started. Finally the pins for the anode and cathode controls are configured as outputs. While(1) { essentially means loop forever. This means that any code contained here will be looped as long as the clock is on. In this second pseudo-function, recieve_packet(); , the microcontroller asks the ENC28J60 for any packets that it has recieved. If there is no new packet, a routine is executed, which we’ll focus on in a moment. In the case that there is a new packet, another pseudo-function, interpret_packet(); , is executed. There are two main possibilities for the nature of this packet. Either it can be a packet containing new configuration options, or it can contain an NTP response from a server. If it contains new configuration options, the new options are written to the eeprom, the new options are loaded into memory, the time variable resets and the clock requests a new NTP packet. If the packet contains an NTP response from a server it is converted into unix time and then stored in the time variable. Backtracking, if there is a no packet received, a series of actions happen. First, the clock checks to make sure that time is set. If it is not, the clock requests a new NTP packet. Next a pseudo-function called time_conversions(); is called. time_conversions(); converts unix time into a readable time in the configured timezone. It separates each of the six digits to be displayed. The six digits of the clock are mapped to variables from left to right. ( hourh, hourl, minh, minl, sech, secl ) Following this, the display(); function is called three times, one time for each anode pair. The display function maps the input, which is what we want to appear on the tubes, to the adjusted output values. By sending these adjusted output values to the 74141 IC we fix the incorrect cathode connections to the nixie tubes. Finally the software checks to see if it is 59 minutes after the hour. If it is, the microcontroller requests a resyncronization with the NTP server. The end effect of this code is that because there is rarely a recieved packet, the display code is looped endlessly. This is responsible for the multiplexing effect and gives the illusion of a continuous display. Configuration: Configuration of the nixie clock is handled through a web browser. There are three configuration pages: http://(clockip)/config, http://(clockip)/options, and http://(clockip)/timing. The config page handles network configuration such as clock ip and timeserver ip. The options page is responsible for display options such as 12/24 hour time, and blank lead zero.The timing page configures the multiplex delay (tweak to eliminate ghosting) and the powersave mode. Config: Options: Timing: Single Board Version: Taking advantage of the lessons I learned constructing my original nixie clock, I recently finished construction of a single board version. Technically it uses two boards, one to hold the nixie tubes and one with all control logic. However, I only needed to produce the control board as the tube holder board was purchased. The two boards are coupled via pin header and spacers. Pictures: Board Layout: Both board bottom and top are availible in PDF format under the attachments section. Partslist: Resistors: 4x 50ohm
3x 270ohm
4x 10k
3x 22k
3x 470k
1x 2.7k
3x 100k
1x 1k
1x 56k
1x 470ohm
1x 220k
1x 2.2k
1x 1k trimpot Capacitors: 1x 330uF (pol)
4x 10nF
2x 18pF
2x 10uF (pol)
1x 2.2nF
1x 100pF
1x 2.2uF, 250V (pol) ICs: 1x ATMEGA168
1x ENC28J60
1x 3.3V Regulator
1x 5V Regulator
1x 555 Timer
2x 74141 Others: 3x MPSA 92
3x MPSA 42
1x IRF740
1x UF4004
1x BC547
1x MagJack
1x 4.7uH Inductor
1x 100uH Inductor
1x 25mhz Crystal Č Ċbottom.pdf (173k)Evan Blair Quirk, Jun 4, 2009, 2:09 PMv.2ď ċntpnixieclockh1.tar.gz (35k)Evan Blair Quirk, Jun 4, 2009, 2:10 PMv.1ď Ċoverallschematic.pdf (108k)Evan Blair Quirk, Jun 4, 2009, 2:13 PMv.1ď Ċtop.pdf (127k)Evan Blair Quirk, Jun 4, 2009, 2:09 PMv.2ď Комментарии
Finished clock
High Voltage Power Supply Schematic

Войти|Последняя активность сайта|Пожаловаться|Печать страницы|На основе Google Сайтов javascript:”

еще и программа исходник

это основная программа . можно изучать изменять и переписывать для своей конструкции – софт открытый. Так же как и Часы на цифровых лампах – там почти такой же контроллер , ардуино mega368p но на 16 мгц. Здесь напряжение на аноды индикаторов 170 вольт переключается на 2 индикатора одновременно через 3 ключа на высоковольтных p-n-p  транзисторах ( надо 16 катодных ключей и 16 лапок у микроконтроллера – нет всего 8 так как 2 штуки К155ИД1 и не надо катодных ключей! микросхемки выдерживают 170 вольт и 60 при работе, они специально рассчитаны на эти лампы! ) . А у меня включено постоянно, 6 дешифраторов 74141 К155ИД1 переключают катоды , а цифра в последовательном коде (arduino shifter) запоминается и переводится в параллельный вид 24 бита с помощью 3 регистров. 74НС595 . А в другой конструкции параллельные 74ls323 . Если на рынке говорят что это прошлый век – так их сотней продают и они в общем то основа цифровой техники – на плате ibm pc 1986 года их штук 30. И Синклер на них собран – вместо оригинального чипа сделали на регистрах и триггерах не считая мелкой логики И ИЛИ НЕ.

https://i0.wp.com/yahobby.ru/wordpress/wp-content/uploads/2021/08/groupings2.jpg?w=1040&ssl=1

 

 

 

 

программа во вложении

 

Download Attachments

Skip to toolbar