My CS80 problem
2005-04-05 by Daniel Araya
Hi My name i Daniel Araya and i'm trying to fix a sick CS80 for a friend. I have gotten it to sing a bit and so far I have fixed a broken oscillator, noise, octave-switch, one broken octave of the keyboard, cleaned the panel, keys, knobs/slidercaps and wooden ends and replaced a lot of missing screws, a few diodes and fixed lots of broken wires and bad solder joints. When I adjusted the filters I found that the squarewave on one of the oscillators sound distinctly different from the others, it sounds distinctly more "reedy" like if it had a different pulsewith. I compared the wave from another card on my scope and the pulswith is exactly the same. One can hardly notice anything on the scope, maybe just a little more "peak" at the top of the rising edge. I propably would see it clearer with a spectrum analyzer, it sounds like something funny is going on with the overtones! Have anyone of you seen this before? I hope the waveconverter-chip isn't broken but I can't see what else it could be... best regards /Daniel, Sweden