Sorting through Grandfathers watches

[zx6rfool]

Recently inherited a box of my Grandfathers watches, nothing valuable, but some cool and some unique items. 

Seiko SQ, my aunt went to Hong Kong in the 80's I believe and picked one up for my Dad and Grandpa. Below are picture, I believe its a 1987 5Y22-8A08. Put a new battery in it and it fired right up! Its probably been a drawer for 20+ years. Looks like he only wore it a few times.

 

Citizen Quartz 46-9181 with a seven jewel 7961B movement. It had what looked like some moisture damage, and a corroded battery. Swapped it with a 371 but it would only vibrate the second hand. Tried trouble shooting while in the case but eventually ended up pulling the movement out and cleaning with some naphtha and blowing it out and running it on the demagnetizer for a while to free up the movement before cleaning the band and case lightly oiling and reassembling everything. Now its back up and running.

Based on the adjustment of the band I believe my Grandmother actually wore this watch, and I made the mistake of telling my wife that. Now its her watch!

The most interesting so far is a 72-73 Benrus.  I tried putting a battery in it, but no joy. Ran it on my little tester, no signal from the coil, tried to spin it up. Just the slightest flicker of the second hand. Put some naphtha where I could reach, and tried again to spin it up. Nope. This watch is interesting in that it does not look like the back comes off, there is a window you unscrew to access the battery, a huge SR44. Ordered a crystal puller and will begin disassembly next week. 

I was able to find a little bit about this watch though a google image search;
BENRUS H010 TECHNIQUARTZ 1972
1st US made Quartz made by Benrus.
Using a custom E-block with the step Motor, a power switch and a Moto Chip driven by MotoQ at 32KHz, on modified ETA mechanical movement.

https://www.crazywatches.pl/benrus-h010-techniquartz-1972

 

[zx6rfool]

Crystal tool came in today, so I gave it a go on the Benrus. Got the movement out and give it a naptha cleaning and was able to spin it up. So that is some progress. But Im not getting a pulse reading, and no movement when reassembled with the battery. Because of the unusual movement Im not sure what to try next. Do I unsolder that huge Motorola crystal and replace with "a modern tiny 32.768Hz tube". The linked site shows that as a common issue. I am a bit concerned with my solder skills on something this size and delicate.

 

 

[AndyGSi]

Before you start desoldering anything I'd try a decent Silver Oxide battery.

What does the other side of the circuit board look like.