My DYI Quartz Tester

[LittleWatchShop]

10 minutes ago, jdm said:

On the other hand probably the ideal all-in-one quartz tester doesn't exist.

I am in the process of building a custom tester based on the Accutron 600 test set.  I choose the 600 because I have a pristine 700 and dont mind hacking the 600.  I like the test set because of the huge 25ua meter!

I am designing a variable battery source using a miniature digital volt meter mounted on a 3D printed module that plugs into the hole in the 600 test set (where the leads are stored).  This is not a "does everything" tester either.  It will let me test for low and high battery voltages, and also test pulse current.

The picture shows the current state of the module--basically got the 3D print done.  The electronics will be trivial.

[watchweasol]

The combination quartz watch testers  are as jdm said over priced   I got hold of one and took it to bits, the cct board is or was then cobbled from somthing else to do the job and the wiring was terrible as was the soldering. I threw it away and only saved the transformer (line release) and built it to another case Its still working which is more can be said for the rest.  I tracked the originol to India but got no response from the people who made it, which was not surprising.

[LittleWatchShop]

10 minutes ago, watchweasol said:

The combination quartz watch testers  are as jdm said over priced   I got hold of one and took it to bits, the cct board is or was then cobbled from somthing else to do the job and the wiring was terrible as was the soldering. I threw it away and only saved the transformer (line release) and built it to another case Its still working which is more can be said for the rest.  I tracked the originol to India but got no response from the people who made it, which was not surprising.

The hard part for me is the mechanical features.  Making probes, holder, mirror and all in a nice station. I am thinking about buying a mini mill to make parts for things like this. Crazy...I know

[watchweasol]

Hi       LWS  There was a Tester/power supply designed and made by Martin Catt, it was on the net   I built one a while ago it works ok and would be a doddle for you I am sure. Have a look at thr pdf's below as they contain all the instructions. Its pretty handy.

catt_pwr-supply_01.pdf catt_pwr-supply_02.pdf catt_pwr-supply_03a.pdf catt_pwr-supply_03b.pdf

[LittleWatchShop]

Some good ideas on the mechanical aspects for sure. 

His circuit is overkill IMO. I have not read or tested to confirm, but I would expect almost no real current drawn by a watch. Therefore the source resistance is no big deal. Using regulators to achieve 0.001 ohms source resistance is not necessary. What is important is an extremely low ESR capacitor in shunt with the watch. 

I am planning on using a shunt regulator and a resistor divider with a pot...a very simple design. At least, that is where my head is now.

Another thing I learned from the docs is the need to go all the way down to 0.8 volts.

Edited December 21, 2021 by LittleWatchShop

[watchweasol]

Hi  to a PHd like youself  probably small beans  would like to see you finished item and methodology

[praezis]

There were even more simple probes, all you need imo.
Just an U-shaped wire, pointed tip on one end, 2 mm plug on the other:

 

Usually a quartz is tested contactless, without opening the watch. A piezo receives its 32 kHz vibrations, processed by a narrow band (quartz filter) amplifier.

Frank

Edited December 22, 2021 by praezis

[LittleWatchShop]

On 9/7/2021 at 4:28 AM, Plato said:

If money were no object then I'd buy a suite of Witschi equipment.

However, the closest I can afford is what I picked up on ebay a few years ago. A Portescap 5007. It has three probes so one for +V, one for gnd and the other to take measurements. I just had to make some leads for my PSU and scope. Under £30 including the connectors:

@Plato, what is the diameter of the viewing window?

[Plato]

12 minutes ago, LittleWatchShop said:

@Plato, what is the diameter of the viewing window?

The tilted mirror? I'll measure it tomorrow afternoon. 

[LittleWatchShop]

51 minutes ago, Plato said:

The tilted mirror? I'll measure it tomorrow afternoon. 

No, the round hole where the watch sits.  I will use that dimension to scale everything else.

 

Thanks!

[Plato]

OK, no problem. 

[Plato]

@LittleWatchShop 26mm exactly.

[LittleWatchShop]

9 hours ago, Plato said:

@LittleWatchShop 26mm exactly.

I designed and printed the base.  Used a mineral crystal that I had taken off another watch when replaced.  Will order a new one...without scratches.

[LittleWatchShop]

@Plato, is the mirror in your setup freestanding, or attached to the workstation?  I have printed a wedge to mount a mirror.  Not sure if I need to attach it to the workstation.

Do you ever test movements, alone, or just cased movements?  I am just pondering the movement/case holding features.

[Plato]

The mirror is screwed to the platform. I've only ever used it with uncased movements, I don't think it's large enough otherwise.

[LittleWatchShop]

4 minutes ago, Plato said:

I don't think it's large

Yeah, I was kinda thinking that.  I am going to press forward with this setup.  First version is just to develop the concept anyway.

[Plato]

It would probably be a better set up if you could use the probes with the movement cased 

[LittleWatchShop]

I decided I needed more viewing area.  Here is the next REV of prototyping.

Picture a little fuzzy but you get the idea

[LittleWatchShop]

I discovered that this thing NEEDS LIGHT.  I cannot see the face of the watch on the glass because it is too dark.

Using a COB LED that I salvaged from a light bulb (one of many) and a dual 2032 battery holder/switch, I cobbled together this solution.

[watchweasol]

Hi Thats nifty all I use is a mirror and a frame with a bit of glass on the top, maybe should inprove it now looking at yours and do a better job  .

[LittleWatchShop]

7 minutes ago, watchweasol said:

Hi Thats nifty all I use is a mirror and a frame with a bit of glass on the top, maybe should inprove it now looking at yours and do a better job  .

Do you have a 3D printer?  I can post the stl files.

Alternatively maybe I could design and print one to fit your glass and mirror and swap for barrels.

Edited January 24, 2022 by LittleWatchShop

[watchweasol]

Hi  My Nephew has a printer and he does bits for me when I need them  thanks for the offer though.    regarding the barrels, The mougin movement, size are approx  36.5 Diameter X 25.5 depth and the width of the ring teeth is 3.5 depth I have a couple of barrels.

[LittleWatchShop]

1 hour ago, watchweasol said:

Hi  My Nephew has a printer and he does bits for me when I need them  thanks for the offer though.    regarding the barrels, The mougin movement, size are approx  36.5 Diameter X 25.5 depth and the width of the ring teeth is 3.5 depth I have a couple of barrels.

This is what I measured the other day while still in the movement.  Looks like what you have is a little different.

 

[LittleWatchShop]

Strategy change.  For now, I wanted to have a variable voltage source to power watches.  This is not integrated with anything.  Just a standalone voltage source with readout.

That is a 10-turn pot, so I can make fine adjustments (though that is not necessary).

Not the best 3D print, however.  My printer has been giving me a few fits here of late.

[LittleWatchShop]

Got tired of wondering voltage so I regulated it and used a 9V source.  Used a shunt regulator because I had a bunch sitting around.