Pics of resealed modules.

[Sully008]

Does anybody have any pictures of resealed modules after you've replaced the batteries in them? I just can't seem to fit the V80s in without a rather large gap to fill in. I can get V40s to fit no problem since they're smaller, but the capacity is not the same.

[clockace]

mike, look in the photo gallery. i have posted photos of 4 of the ones i have sealed. they are showing both sides. i don't know why you are having the problems you are. are we using the same tops and bottoms that the mkI/II's used? maybe you could post some photos of what you have and perhaps we can see what the problem might be. regards, peter

[Sully008]

Hi Peter,

I took a look at your pictures and mine don't even come close to closing like that. The only way I can get it completely flush is if I use V40s. I just tried using a pair of V80s with solder tabs on it and it's still a good .0625"-.125" from closing shut. I'll try and get some pics of the rather horrid job I did. Almost ashamed, really.

Mike

mike, look in the photo gallery. i have posted photos of 4 of the ones i have sealed. they are showing both sides. i don't know why you are having the problems you are. are we using the same tops and bottoms that the mkI/II's used? maybe you could post some photos of what you have and perhaps we can see what the problem might be. regards, peter

[charger105]

Some of the red bottoms have tab recesses, and some don't (a rectangular recess extending from the round recess). Do the ones you're using have these recesses ? Also, the round battery recesses are slightly different in size, meaning one V80 fits nicely, and one doesn't. I have used one V80 and one V40 before to overcome this without having to 'attack' the lexan bottom.

See here for one without the tab recesses:
http://www.ledwatches.net/photo-pages/s ... nsides.htm


Rgds.

[charger105]

Upon closer inspection, the bottom below does seem to have a tab recess (on the left side).

http://www.ledwatches.net/photo-pages/s ... nsides.htm

I'm sure I've seen them without though.
Rgds.

[clockace]

i think they all have tab recesses. at least all of them i have seen do. the tab recess is not all that necessary i have found. i cut the tabs fairly short, pierce them with a hole about the size of the lead wire, poke the wire thru and solder. i put them in with the + side up on both of them. then you can bend/press the tab down against the + side/edge of the cell. nothing extends into the tab recess of the back if you do this. the recesses of both cells will need to be enlarged for clearance. the smaller one also needs to be made larger in diameter. in particular, the outer edge of the recess needs to be ground away for clearance of the lip on the cell. i use a foredom grinder and burr that cuts both on the end and the side. i will try to post some photos of this process. one problem i have not had is getting the red back to close flush. see the photos on the photo gallery. i have sealed 4 of them so far. the rest that i have running are still in the checking out phase and held together w/scotch tape until i am satisfied with performance. peter

[charger105]

Here's a picture of a Mk1 or MkII bottom without the tab recesses:

http://www.dwf.nu/Gallery/displayimage. ... at=0&pos=0

I find it helpful to use the recesses, if present (no sharp bending of the tabs) or grinding of the recess.
I can also recommend using one V40 and one V80. It works fine, has more capacity than the original(100mAh), and is far less destructive than grinding away at the bottom so that the 2nd V80 will fit. To re-iterate, you do not need to modify the bottom at all if you use one V40 and one V80.

I generally solder the batteries together with a short link, 'tin' the upper tabs, and silicon them in place on the lexan bottom to hold them in place (clamped with pegs). Once cured, all you have to do is touch the two wires from the module with the soldering iron to secure them to the bottom/battery assembly, and then snap it shut !

It should all fit easily. You can put pieces of plastic film under the upper tabs, and bend them down, and a piece to shield the PCB/components too.

Hope this helps.
Rgds,
Andrew.

[Sully008]

Andrew/Peter,

Thank you both for your help in this matter. I have both styles of bottoms with/without tab slots. Peter has given me some tips on how to get more depth in the Lexan case, and I'm going to try your V40/V80 method on one of the one's that has 2 V40s in it, Andrew.

This has been a frustrating part of the restore process for me. I knew others had done it without a huge gap to fill. Thank you again both for your experiences.

Mike

[Snetzka]

Guy's.
Mixing a 40mAH cell with a 80mAH cell will not give you anymore than the lowest cell capacity, in fact when the cell with the lowest cell has been drained (40 mAH) the other cell may try to charge the now flat cell.

At best you will achieve the same as 2 x 40mAH cells.

Series Connections
When a battery is constructed from group of cells connected in series, the battery voltage is the sum of the voltages of the individual cells, but the mAH capacity is the same for the chain since the same current passes through all of the cells.
Thus a battery constructed from 2 X 1.2 Volt X 80 mAH cells will have a battery voltage of 2.4 Volts and an mAH capacity of 80 mAH.
 
Parallel Connections
When the same 2 cells are connected in parallel, the battery voltage is the same as the voltage of the single cells, but the mAH capacity will be the sum of the mAH capacity of the cells since the current through the load is the sum of all the currents through the individual cells.

BUT. Batteries should not be made up from mixed cells. Do not mix cells of different ages, different sizes, different voltages, different chemistries, different capacities, different shapes or different manufacturers. Mixing cell types within a battery can lead to some cells being overloaded leading to early failure and this could be dangerous.

[clockace]

yuuuppp, i have always felt that to be true, but not being an electronics wizard, i did not feel i should butt in and make a fool of myself. just as you would not try to put a "D" cell and a "AAA" cell in your flashlight. the "AAA" would discharge quickly and draw down the "D" prematurely. i do have 1 synchronar that i have repaired running very well on 2 v40's. however, on the days i wear it i do not try to lite up the display 10 times/hr. it may not handle that load. peter

[Sully008]

Hello all,

Well, it seems my lower back is better so I will get on this some time next week. I will try and get the two V80s to fit, I had a loose bottom laying around and did some test fits with batteries. I think I can get this to work. Thank you all for your insights and experiences.

[charger105]

Apologies for giving you a bum-steer Sully. Snetzka's clarification makes a lot of sense (thanks Snetzka). Good to hear you hadn't already put the 2 different cells into your watch.

Having said this, mine have been working fine for quite a while now. One of them I wear several days a week, and it has behaved flawlessly for about 6 months now. However, I'll keep an eye on them in case of premature cell failure, and put two V40s in if this happens.........this is a luxury I have since I have only sealed them with silicon.

BTW, I have a MkIII with two V40s that is working perfectly. I didn't want the batteries anywhere near the exposed IC, so stuck them down in the bottom as far away from the IC as possible. I destroyed another MkIII using two V80s when I closed it up. Even if the batteries don't touch the IC or wire-bonds, if there is jelly in the way, and it is stressed, it seems that it can pull a wire bond off.

And clockace, don't be afraid to make a fool of yourself.......I do it regularly !

Rgds.