Junghans 620.00: bad manufacturing

 This one was torture. The movement had a broken escape wheel and missing exit stone so got a 620.52 donor movement.

However the movement was basically unservicable due to every steady post in the movement being extremely tight, badly finished or even crooked. So this movement commits the worse sin of all: horrible manufacturing.

The balance wheel was also warped and while trying to get the hairspring out it broke. 

 The donor did not have the same problems but unfortunately it did not fit in the case.

 And that horrible integrated barrel arbor/ratchet wheel design is just horrible.

I want to forget I ever came across this movement. An expensive lesson.

 

 

 

How to add live escapement audio to a Weishi timegrapher: a guide

 In my previous post here https://www.blogger.com/blog/post/edit/1111331671787346124/4208845159537743819 I made a box that allows connecting a Weishi timegrapher's microphone to a computer or powered speaker. That can be very useful for long term recoridng and diagnostics by using some timegrapher application on a PC.

 Now I'm explaining how to add live audio of the escapement to a Weishi. The resons are the same as before: the pre-recorded audio of the Weishi limits usefulness and I don't want to spend 3000 euros on a pro-level timegrapher.

What's needed:

• GX 16 3 pin male to female Y splitter. The male end connects to the timegrapher speaker, one female end goes to the timegrapher and the other to the speaker.
  
  
  
  
  
   
  
  
   
   
   
• GX 16 3 pin male adapter. Two of these pins will connect to the AUX cable.
  
  
  
• Speaker AUX cable. This is a bog-standard 3.5mm speaker jack.
• A speaker with AUX input. I got a cheap one from AliExpress and it works fine. A wireless speaker will reduce desk clutter. 

How to:

1. Keep wires relatively long as feedback can be an issue. 
2.  Cut out one of the AUX cable's ends so that you're left with one male AUX end and the other end with bare wires.
3. Figure out the wiring for the tip and sleeve, i.e the top and bottom parts of the connector. The middle part, the ring, is not needed. In my case red was tip and blue was sleeve and the extra cable wasn't needed.
4. Connect pin 1 of the GX 16 adapter (blue wire) to the AUX cable's tip wire (red).
5. Connect pin 2 of the GX 16 adapter (brown wire) to the AUX cable's sleeve wire (blue).
6. Connect AUX to the speaker, microphone to the Y splitter and Y spliiter to both the timegrapher and the GX16 adapter.

 

 

 

 And a recording of the result with live escapement audio from a movement, EB 1333 in this case. You can even hear an escapement problem in my recording that corresponds to issues in the graph.

 

 

 

Sotwa with FHF 59-21: A tiny movement that is a joy to work on

 This one was easy and straightfoward except for rust in the escape wheel's pinion leaves. The dial was in a bad state too and it seems that either there was no lacquer or it was completely damaged because the standard cleanup of water, a qtip and rolling gently removed some letters. Kinda disappointing but a lesson learned.

  

On the timegrapher, before service. Not too bad but it is obvious something was wrong here. Pretty sure it was the rust in the escape wheel's pinion wheels.

 

Small but mighty.

The escape wheel before and after, huge difference after polishing with dialux and a pointy stick.

Timegrapher results. Before

Position	Rate	Amplitude	Beat Error
DU	234	324	5.9	?????
DD	337	177	4.1
CR	448	335	5.8	?????
CD	502	289	7.1	?????
CU	429	123	4.9
Delta	268
Mean	343.2	184.8	4.38

And after.

Position	Rate	Amplitude	Beat Error
DU	19	283	0
DD	2	310	0.1
CR	-4	269	0.2
CD	5	283	0.2
CU	-3	279	0.1
Delta	23
Mean	0	228.2	0.12

Quite the improvement. Quite some difference between DU and DD and I suspect it is a problem with the escape wheel not having been replaced. But it was good practice and got respectable results after manually polishing between the pinion leaves of such a tiny wheel.

Overall happy with this one, except I wish I didn't touch the dial. I've also been enjoying working on FHF movements, they're well built and easy to service.

                                                                     

 

Connecting Weishi timegrapher microphone to PC: a quick guide

The Weishi timegrapher uses pre-recorded audio for escapement sound. Although this is fine to get a sense of the beats per hour it is not useful for anything else as proper diagnostics require listening to the escapement, something that is only available on the prohibitavely expensive pro-level stuff. This also means that you cannot use a computer as a timegrapher with the Weishi microphone attached; you need to use the timegrapher. Which is fine unless you want to track the watch over a long period of time. 

The microphone uses GX16 connector and has some electronics onboard that require power. Unfortunately this means that it isn't possible to just get a cable adapter but it is possilbe to build a small box that does the conversion.

Credit for the idea and circuit go to ONXYApp on youtube https://www.youtube.com/watch?v=As2ZPJsmJBM. THIS IS NOT AN ADVERTISMENT AND I'M NOT AFFILIATED. I just wanted to do this and their circuit diagram came in handy. I don't use any of their software.

 

What you will need

- GX16 male plug. 3 pin.

- 9V battery.

- 9V battery clip

- 1000 Ohm, i.e 1K, resistor. These are 1W rated but you can use lower rated ones, it is fine.

- 1uF capacitor

- Slide switch

- 3.5mm TRRS, i.e four pole male plug

- Small electronics box

- Soldering iron, solder and optionally some sort of helping hands tool.

- Multimeter ideally. 

 

That's all the supplies. You can buy them wherever but Aliexpress was pretty cheap so you can get spares. I plan on making mine nicer eventually, maybe with some circuit board. Also helps if you end up breaking something.

 

 

Circuit Diagram

 

Circuit is really simple, just a battery, a capacitor, a switch and a resistor.

 

How to

Please note that when it comes to wire colors your mileage may vary, I have used the colors my connectors came with. A multimeter will allow you to check what wire is connected where to avoid any problems. Doing this incorrectly might break the timegrapher's microphone.

1. Cut two holes in the box, one for the GX16 (~14.5mm) plug and another for the 3.5mm (~3.5mm) jack on opposite ends.
2. Cut a small slot for the switch.
3. Take the 3.5mm jack and push the wire end through the hole.
4. Insert the GR16 male plug into the hole. In my case the washer and nut did not fit the case but the hole is tight enough that it doesn't matter.
5. Cut the jack's red and white wires (Tip and top Ring), leaving the black and green wires (bottom Ring and Sleeve).
6. Solder the resistor between the jack's black and green wires.
7. Solder the capacitor to the end of the jack's green wire.
8. Solder the other end of the capacitor to the number 2 pin on the GR16 plug. This is the pin that stands alone at the bottom. Blue wire.
9. Solder the end of the resistor on the black wire side to the number 1 pin on the GR16 plug. This is the top left pin when looking at the plug straight on with the notch placed at top. Brown wire.
10. Solder a wire from the wire you just connected to the resistor to the switch's middle pin. I just used part of the plug's wire that was too long.
11. Solder the negative (black) wire on the 9V battery clip to the number 3 pin on the GR16 plug. This is the top right pin when looking at the plug straight on with the notch placed at top. Yellow and green wire.
12. Solder the positive (red) wire on the 9V battery clip to one of the switche's side contacts. This will be the ON position.
13. Place everything in the box neatly, don't short anything.
14. You're done.

You should now be able to connect the timegrapher's microphone to the box and then connect the 3.5mm jack to a microphone input of your choice. In my case I am using a Focusrite Solo 3 audio interface (again, not sponsored, purchased with my own money) because I wanted to have the direct monitoring feature where I can listen to the microphone's output via headphone connection. I don't think you need this part and a stard 3.5mm microphone input will work (still have to try this).

 

Turn flip the switch to the on position. If your audio interface supports monitoring and pretty high gain you should be able to listen to the watch directly.

 

 

 

There's various timegrapher software you could use this as input to. In my case I'm using xyzzy42/tg https://github.com/xyzzy42/tg which is an open-source fork of the TG Timegrapher. Needs to be compiled.

 

Problems

- Audio is kinda noisy and I suspect this is because of the cut wires or some grounding issue. Could also be because I'm using a 3.5mm to two pin 6.5mm adapter to the audio interface as I didn't have a TRRS adaptor. I'll get one and we'll see.

- Volume is really low but that's expected as there's no amplifier in there. Timegraphers pick it up just fine. The Solo has a gain control which really helps with this.

 

Sample recordings

These are recordings from some watches I have.

 

• ST36, practiced on many, many times. Maybe 30 or so disassamblies?
  
• Chinese 7750 clone as purchased
  
• Unknown 1 jewel movement, Roskopf escapement
• Velona 1100 ETA 2409 serviced known rate fluctuation and pallet stones need replacement
• NH35A with a broken mainspring
• Unknown movement from 1930s, unserviced 
• Elgin grade 303 model 3 unserviced
• Tudor Black Bay 58 
• Yema watch, unknown movement, not serviced
• Junghans 620.10 unserviced 
• Wostok 2605 unserviced
• Quartz 
  

Iaxa FHF 96-4, late 1960s

 A good workhorse from an obscure, prolific Belgian brand that was mostly active in late 1960s to mid 1970s, sold through stores in Belgium and the western part of France. No literature remains about the brand, no marketing material or newspaper info.

Jacques Meyer registered Chronomètre Iaxa in 1903 and was based in La Chaux-de-Fonds, Switzerland, in December 1913 the brand was transferred to Les Fils de Jacques Meyer, in Brussels. The Iaxa brand was registered in Brussels in August 1944. Little more is known of this Belgian brand other than a Jean Meyer was "Director General" from 1965 to 2006. It is quite likely that Iaxa actually ceased trading towards the end of the 20th century. 

Movement just needed a service and a new setting lever spring and works incredibly well for the age.

Before servicing

 

Position	Rate	Amplitude	Beat Error
DU	-16	308	1.5
DD	-22	319	1.7
CR	-37	245	1.8
CD	-39	266	1.8
CU	-39	266	1.8
Delta	23
Mean	-30.6	280.8	1.72

And after 

 

Position	Rate	Amplitude	Beat Error
DU	5	324	0
DD	0	314	0.2
CR	0	254	0.5
CD	-1	256	0.4
CU	1	249	0.1
Delta	6
Mean	1	279.4	0.24

Show off opportunity: Fero EB 1333 pin pallet escapement, a movement from late 1950s hell

 

This one kinda ran, but only occasionally. Would randomly stop.

It uses a pin-pallet escapement (Roskopf) so the 17 jewels on dial, while true, is extremely misleading. It is a cheaply made disposable piece of crap that needed a huge amount of work.

The mainspring, regulator pallet fork needed replacing.

Broke the escape wheel top pivot by mistake as the lower cap jewel wasn't installed when installing the train bridge. Lesson learned. 

Three cap jewels needed replacing.

The hairspring was out of round and out of flat. Hairspring work has to be the thoughest part of servicing watches. took a long time to get right.

Before. Who knows what happened here, but something did happen.

 

 

And after.

The third wheel also had rust and pitting between the pinion leaves. So dialux and a wooden skewer were used.

 Even polished the setting rocking bar and dial-side cap jewel settings, because why not.

 

All this work and effort, for what? The timegrapher results are sad.

Cased and left to run for 24 hours then will re-check. But this one got the royal treatment that would have been really expensive and a task no professional would probably accept.

 

 Then, touched the regulator and dial up stopped working. Too much endshake. Oh well, leaving well enough alone for now, I'm fed up of this movement. I'll adjust the endshake when I get the Horia tool.

Update: the balance top cape jewel became loose. Closed the hole again, re-inserted the jewel and will let it run for a day or two but the results are really promising. I managed to get a low quality movement that's almost 70 years old to work better than it did when it came out of the factory. This is the sign that I've gotten simple wrist watch servicing and basic repairs, jewel replacements and ahrispring work, down. I have a couple more watches that need servicing and after those I'll be moving on to tougher repairs with an inital focus on bushing worn pivot holes.

 

The timegrapher results after fixing the loose cap jewels are impressive, for such a bad escapement. I'm proud of this one.

Position	Rate	Amplitude	Beat Error
DU	61	273	0
DD	63	277	0
CL	-32	228	0.1
CD	-1	229	0.3
CU	-19	232	0.2
Delta	95	49	0.3
Mean	2.2	193.2	0.12