I got a speak and spell off of that soul-sucking pit known as ebay and it's keypad matrix is f*ckered. I found an on/off bend on the circuit and a few glitches, but other than that it seems to be a pointless endeavour. is there any advice to remedy this or should i just condemn the unit to the firey depths of... a fire? Any help/advice/death threats would be appreciated.
I sympathise - really. Years ago I had an accident with a keyboard on an old MSX computer... dammed gravity...
Anyway. About your problem, and the above bit was related to it.
There may be a solution...
assuming that there's actually some dammage to the board in question. (ie the bit with the keyboard matrix on it)
Firstly - get a small basic circuit tester, the kind you get from maplins for about 10-15 quid should be more than enough.
use the said tester to see if there's any voltage/current/electric at all going across the keyboard matrix.
If not - the find out where along the line has this activilty stopped..
This is the awkward bit !!
where this break is occuring, get a very VERY fine file, and remove the a bit of the covering on the circuit board from the offending tracks.
Next - get youself some soldering flux (the solder with it inside is ok - but I find flux is most effective on freshly cleaned exposed copper track) and with this and solder, tin the bit of offending track.
Now - assuming you're on a part of the track that isn't intterupted by the presence of a component , simply make a jump over the bit off dammage/malfunction using a fine-gauged peice of insulated electrical wire.
Repeat these steps, until you can find no-more useless/dammaged points when testing.
When this is done - you should've effectivley by-passed the dammaged areas, thus making it useable.
HOWEVER this, of course assumes that the problem is cracked/dammaged tracks on the circuit board...
If it's something more obscure - then this advice isn't of much use
thank you for your sage-like advice. I removed the keypad from the front cover and pretty much all the circuit has corroded and it's a crying shame. I've managed to find some parts on the main pcb that can still cause some noise and random glitches, but it's very tempermental and crashes frequently. I think it can still be used on a more basic capacity though. I might just have to add some smaller circuits to the box just to fill out the sounds.
I'm quite interested in wiring it to my S&M but i'm not sure where to start on that one