Starting on quartz

[JohnD]

One of these is 'useful'........

I dread to think what they cost new about 40 years ago....

[LittleWatchShop]

29 minutes ago, JohnD said:

One of these is 'useful'.

The challenge in making a DIY one of this is the sensor.  I suspect it has two modes 1) sensing the 32767 crystal frequency, and 2) sensing the stepper frequency.  The stepper emits more energy I would imagine...and thus easier to sense. 

The energy is confined somewhat in the Faraday shield of the case--making it more difficult problem for the sensor.  I need to try making the sensor. Another shiny object

[JohnD]

1 minute ago, LittleWatchShop said:

The challenge in making a DIY one of this is the sensor.  I suspect it has two modes 1) sensing the 32767 crystal frequency, and 2) sensing the stepper frequency.  The stepper emits more energy I would imagine...and thus easier to sense. 

The energy is confined somewhat in the Faraday shield of the case--making it more difficult problem for the sensor.  I need to try making the sensor. Another shiny object

It does a lot more than that....I've even been able to time a Timex jump minute hand quartz that only emits one pulse every 60 seconds..... They do appear for sale  occasionally. I got very lucky and picked mine up a couple of years ago for less than £200, but I did have to drive a 240 mile round trip to collect it as I wouldn't trust a carrier with it! This is a useful document......

1189973045_1980.07SeikoTechnicalGuideGeneralInstructionAnalogQuartz.pdf

[LittleWatchShop]

44 minutes ago, JohnD said:

It does a lot more than that....

I see.  Very nice technical document.

OK, so I went to the lab and grabbed what I figured had the most turns (coils) and set it up with the oscilloscope.  No additional circuitry.  Wow...picked up the stepper motor with a huge amplitude.  Here is the scope output and the simple setup.

With additional circuitry, I could measure the frequency of these pulses (or rather the time elapsed between them).

[JohnR725]

1 hour ago, LittleWatchShop said:

Regarding electrolytics...they indeed age.  It is more of a problem with switch-mode power supplies than these analog ones.  I will look into it.  I have repaired several otherwise dumpster flat-panel TVs by simply replacing the caps in the main SMPS

If you take your timing machine apart you'll notice the circuit boards plug-in nicely. There is usually a date code on all the circuit boards and definitely the one or two integrated circuits. It's been a long time since I've replaced the capacitors in several of these and I vaguely recall late 70s. As this is a workhorse machine found in almost every watch shop around the planet where likely for at least 20 years they were on and running not necessarily timing but they were on and sitting there. The capacitors either have dried up or a few leak. But as long as it's running don't worry about it.

2 hours ago, LittleWatchShop said:

That is the "skin drawer" as my dad called it.

I was trying to remember what the technical term for it is? I liked mine so much I filled it with stuff and its support broke. Ideally are supposed to keep it empty and pulled out your waist then any of the parts to try to commit suicide by jumping off the bench are saved by landing in the safety net for safe retrieval. But conveniently missing off modern watchmakers pinches. Plus it was just a handy place to do stuff at a lower level than the top of the bench.

 

[HectorLooi]

Do not automatically assume that the old 70's capacitors are bad. I restore old dental equipment and hifi amplifiers. I frequently come across 40 year old capacitors that are still up to specs. Somehow things were built to a higher standard in those days.

The "skin drawer" is also seen in jeweller's workbenches and dental laboratory workbenches. It was to catch the gold dust from sawing and drilling gold pieces.

[LittleWatchShop]

Returning the original topic now...

I have an ISA 389 movement in a watch that I gave to my wife years ago.  Also years ago, it quit working.  I recently took it apart to see what I could learn and started looking for a replacement movement.

Today, I decided (in the spirit of this thread) to troubleshoot it and attempt a repair.

I discovered that the coil was an open circuit.  This is due most likely to a battery leaking and the acid eating away at the wire on one end.  I could see the green sludge on the wire.  As soon as I touched it, it disintegrated.  However, there was still enough pigtail that I could carefully grab it and unwind it by one turn.  All of this done using a stereo microscope at 40x magnification.

I did unwind it and laid it over the PC board where it need to be soldered.  Moving to the electronics workbench, I used a relatively large (by these geometries) tip and super fine solder and soldered the other end of the coil.  A quick measurement indicated that I should be back in business.

Installed the battery and VOILA!!!

I wish I could have taken pictures of this, but I do not have the right gear for that. 

At the end of the day...you can repair these quartz movements!!!

[JohnR725]

 I have a link to a commercial tester the Horotec Flashtest Which while not as cheap as I would like considerably cheaper than buying a witschi machine. Then in the back of the manual it lists the specifications for a variety of quartz watches.

I'm also attaching a Omega document listing the specifications for their quartz watches.

Then the second link is an example of what the watch companies were doing in the day on page 32 citizens tester for quartz watches.

https://www.cousinsuk.com/product/horotec-flashtest

http://www.awci.com/wp-content/uploads/ht/1985/1985-12-web.pdf

8641_WI_18_QUARTZ MOVEMENTS - TECHNICAL CHARACTERISTICS E cousinsuk.pdf horotec quartz watch USER_MSA19.115_en.pdf

[LittleWatchShop]

On 2/2/2021 at 1:14 PM, JohnR725 said:

 I have a link to a commercial tester the Horotec Flashtest Which while not as cheap as I would like considerably cheaper than buying a witschi machine. Then in the back of the manual it lists the specifications for a variety of quartz watches.

I'm also attaching a Omega document listing the specifications for their quartz watches.

Then the second link is an example of what the watch companies were doing in the day on page 32 citizens tester for quartz watches.

https://www.cousinsuk.com/product/horotec-flashtest

http://www.awci.com/wp-content/uploads/ht/1985/1985-12-web.pdf

8641_WI_18_QUARTZ MOVEMENTS - TECHNICAL CHARACTERISTICS E cousinsuk.pdf 118.01 kB · 1 download horotec quartz watch USER_MSA19.115_en.pdf 405.1 kB · 1 download

Great stuff.  This turbo feature is interesting (and new to me).  I guess the issue of train-wheel lock up is a reasonable probability--would not have thought that.

I am taking delivery on a new (another) watch bench in a couple of weeks, so I will have all this extra room for MORE stuff!!

[JohnR725]

5 hours ago, LittleWatchShop said:

This turbo feature is interesting

Often times you'll see in discussion groups that their idea of cleaning a watch is to use this feature. It's assumed that quartz watches really don't need to be cleaned and if you spin the train fast and it runs that's equivalent to cleaning which it's not. But it does get stopped quartz watches running and buys them extra life. Which he used to have a really nice one with little knobs to adjust to change the poll's web then the rate and unfortunately was expensive. Here's a link to a cheaper one.

https://www.startimesupply.com/merchant2/merchant.mvc?Screen=PROD&Store_Code=1&Category_Code=HOME&Product_Code=MSA19-107

 

Then thinking about witschi here's something they have on understanding quartz watches

https://www.witschi.com/assets/files/sheets/Knowledge Quartz Watch.pdf