SC810 radio balance control mod

[pogo]

As a new owner of '94 Volvo 850 I was very surprised that stock SC-810 radio has no balance control. I've decided to fix this and modify fader to act as balance - who needs fader anyway?
First you need to pull radio, remove faceplate and then remove big printed circuit board behind the faceplate (the one with switches and bulbs). You can find instructions here, as well as on other places:
http://volvospeed.com/vs_forum/topic/8357-93-volvo-850-radio-light-replacement-notes/
When you turn the board backward it should look like this:

DSC00002A.JPG (42.04 KiB) Viewed 1062 times

Here is a closer look at squared area:

DSC00004e.JPG (37.32 KiB) Viewed 1062 times

What we need to do is to swap Front Right (FR) and Rear Left (RL) channels. This can be done by breaking connection between FR pin and resistor close to this pin and also connection between RL pin and his resistor:

DSC00004f.JPG (38.88 KiB) Viewed 1062 times

Use very sharp knife or needle to remove copper. You don't need to dig a lot - the connections are pretty tin and will remove very easy. Be careful to not cut or damage surrounding connections. Blow the board to remove all particles left. Check the connectivity (actually lack of it) before next step.
Solder 2 new wires as follows:
- from resistor near the FR pin to RL pin
- from FR pin to RL resistor.
"A picture is worth a thousand words”:

DSC00004g.JPG (45.6 KiB) Viewed 1062 times

Here is a final result:

Check everything, replace the board and test without faceplate (you have radio code ready, right?). If everything work well, reassemble faceplate, put the radio back and enjoy.