Poker 2 Repair - Nonworking Keys

[Hitcha]

First and foremost, my apologies if this isn't the correct forum for this type of post.

Hello GeekHack I am in need of some repair advice.

I'm reconstructing an older Poker 2 board that was sitting around, and after resoldering all of the switches five key don't work. These keys are the 1 key, and the Z, X, C, V keys (which are right next to each other).

After removing the switches, I found that the trace leading to the 1 key and the trace leading to the Z key are damaged beyond repair. I was able to build a jump to get the 1 Key working again, but the Z, X, C, and V keys still do not work at all.

I'm pretty confident that the Z key is responsible for the other keys in that row also not working correctly. Unfortunately I have no idea what keys should I should bridge with wire in order to get the Z, X, C, and V matrix working properly again, or if I should just wire them all to get them all working properly.

Here are pictures of what I've done so far: http://imgur.com/6ncRqyu

If you have any advice or tips, it would be very much appreciated! Thank you for your time.

[suicidal_orange]

You've got the right idea - you always need to connect the non-working key(s) to a working one to get them back working.

As you say there is a pad missing on Z and everything else looks OK, so we'll assume the problem is purely there.  That pin will need to be connected to X - you've done that.  It also needs to connect to the other side, confirmed by you connecting V to B which didn't fix them all.  The next key over (the unused ISO one) is wired in the matrix in the row above, so skip that one and solder a wire between Z and Shift - that should fix it

[jcoffin1981]

You may find that one of the leads from the switch pad leads to the diode.  If this is where the trace is severed you can solder a wire from the switch lead to the diode.  The other pad if you look carefully may not be attached to any leads or traces.  It's just a solder point.  The switch lead actually makes contact on the other side of the pcb.  What you can do is with a very this gauge wire ( you may have to sand it down thinner) melt the blob of solder securing the switch and have the piece of wire make contact at the edge of hole on the keycap side of the pcb.

This is a real pain in the arse and I find no matter how careful you are, Poker boards in particular always lost a trace or pad when desoldering.  I'll see if I can draw you a pic to better understand.

[tp4tissue]

This is hard from looking at the foto..

I'd also like to check the other side, since it looks like there are through traces..

What I'd do in this case,  is free float the last wire,  and touch it to the ground pin of -F- or -G-

See if that gets it working..  as -B- might have a different trail for the matrixing..



The thing I'm worried about is still through traces.. if there's something on the otherside that needs to be connected..  i recall poker 2 had nkro via usb, so maybe there's some complication due to that.

[jcoffin1981]

It's actually fairly simple, just tedious.  It's much harder with LED's.  I think that the pad on the bottom connects to the pad on the other side, which connects to the trace.  Now you can also strip 2 ends of a 5" piece of wire, solder it to the switch leads, and then make it connect to various contact points and depress the switch and see where it  actuates.  Unless the PCB is totally melted you can make a proper contact somewhere.  Without the pad the solder will be very difficult to flow through the hole, hence the piece of wire making contact at the edge of the opposite side

You are not the first person this has happened to and I'm sure somebody can chime in with their own technique for correcting this, possible better or easier than mine.  You can use Suicidal Orange's technique of soldering to adjacent keys, I just don't a zillion wires running around the bottom  of the pcb.  Perhaps his way is the more accepted way?

I've also had success putting a miniscule amount of solder at the base of the switch lead and at the plastic.  It's got to be paper thin or the switch won't sit right, but this will also make contact on the key cap side of the pcb.

[LiquidEvilGaming]

How exactly do PCB traces get damaged beyond repair?  Was it something you did personally?  Or did it actually happen on it's own through time and use?

[suicidal_orange]

How exactly do PCB traces get damaged beyond repair?  Was it something you did personally?  Or did it actually happen on it's own through time and use?

Usually it happens when desoldering a troublesome switch - too much heat and/or heating it too long then the pad comes off, as happened on the Z key in the pic in this thread.

Another less common way is scratching through a trace when your screwdriver slips while unscrewing the case.

It's rare that they just break but it does happen, more often on PCB mount boards (the plate takes most of the strain if there is one)

[LiquidEvilGaming]

How exactly do PCB traces get damaged beyond repair?  Was it something you did personally?  Or did it actually happen on it's own through time and use?

Usually it happens when desoldering a troublesome switch - too much heat and/or heating it too long then the pad comes off, as happened on the Z key in the pic in this thread.

Another less common way is scratching through a trace when your screwdriver slips while unscrewing the case.

It's rare that they just break but it does happen, more often on PCB mount boards (the plate takes most of the strain if there is one)

   Thanks for the detailed response I was genuinely curious.

[jcoffin1981]

I've desoldered 2 v60's and 2 pokers, which still makes me kind of a newbie.  The pokers each has a few damaged traces and the v60's had none.  The poker traces and pads seem to have less  adherence to the pcb underneath or or less of whatever covers them.  Yes, there always seems to be a few switches which prove difficult to remove and these are the ones that get damaged.  I've found that wiggling the switch contact seems to better melt all the solder and pull it together, making it easy to vacuum it up.  Dealing with broken traces it quite a nuisance. 

[Hitcha]

Hey guys, thanks to your help I was able to get the keyboard working again; finally found a jump that makes all of the keys proper once more. I jumped the Z and X keys, and then jumped the X key to the . key. Thanks again for your assistance, you guys rock! 

[jcoffin1981]

I'd love to see a pic of the finished pcb.  You may have already reassembled in which case you don' t have to take the time.  But if you have an image or two please post.