Help with odd pcb problem

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Help with odd pcb problem

Postby Text_Edifice » Sun Sep 04, 2016 8:55 pm

Have been trying to fix some dodgy group modules on a little d&r console and haven't had any luck going through the normal Cap / ic ch we checks and changes.

Then I noticed that, there is a break in the board (seemingly by design) between the left and right only Jack's. On the one working strip these are linked by solder bridges. On the three dead strips these bridges aren't making contact.

See https://www.dropbox.com/s/p42t4p2orpopf ... 2.jpg?dl=0

Any ideas how to fix this?

I am guessing I'll have to either excise the trace and solder a jumper or drill the boards to achieve the same end.
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Re: Help with odd pcb problem

Postby Wiz » Mon Sep 05, 2016 7:01 am

Unless I am misunderstanding... which is a fair chance :D

I would just trim some component leads (resistor) and bridge it... seems weird though... having two seperate PCBs joined only by solder bridges...

Do you have a working group module, that you can look at and check its the same?

cheers

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Re: Help with odd pcb problem

Postby Text_Edifice » Mon Sep 05, 2016 7:49 am

This is the working module.

https://www.dropbox.com/s/vlo34m9i71j4e ... 8.jpg?dl=0

It is weird...

I guess the problem is I can't see how whoever did this managed to get the solder to make a connection with the track. My skills aren't up to fixing it that way.

So - expose the track and carefully solder a jumper in place?
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Re: Help with odd pcb problem

Postby Text_Edifice » Mon Sep 05, 2016 8:02 am

Looking at the pcb overlay of the schematics it does seem the strip was designed this way.

https://www.dropbox.com/s/fb1qlrv5vwa5n ... s.jpg?dl=0

I can't for the life of me figure out why.
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Re: Help with odd pcb problem

Postby chrisp » Mon Sep 05, 2016 10:56 am

It doesn't look like you need to expose the track - there are seven pairs of solder pads already there ready to be linked.

As Wiz says, trimmed off resistor leads make for great bridges in this situation - they will create a stronger link than solder. I bend the leads into a U shape, with the length of the bottom of the U being the distance between the pads. You can then solder it in place holding the lead with pliers, and trim the uprights.
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Re: Help with odd pcb problem

Postby Text_Edifice » Mon Sep 05, 2016 11:07 am

solder isn't sticking to the pads - I'll give them a really good clean and fingers crossed that might work.
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