I picked up a Roland KR-350 digital piano for my brilliant grandkids so they can learn...it was $20 on craigslist because of "screeching sound after awhile"...
I assumed it would be capacitors...have replaced all the surface mounts, and replaced the power supply amp chips, voltages all seem to be within reasonable specs...
When I first got it, it would turn on, light up the led's you could play a note and it was like the reverb would stick...then it would start making weird noises and sputtering eventually screeching...now it does nothing at all...the led's do not light anymore even though I am getting ample voltage to them...
It has turned into one of those stubborn "me vs it" situations and is owning my bench...without a schematic its like looking for a specific needle in a needle factory it could be a ton of things...
I have ruled out the power supply because the voltages marked on the board are all correct, all capacitors/resistors are in spec..diodes all check out...
Anyone have any idea where an actual service manual for this might be found?
I have a users manual and found a synth page that has a LOT of roland stuff but just not this mobo...
http://www.synfo.nl/pages/servicemanuals.html#sm
I assumed it would be capacitors...have replaced all the surface mounts, and replaced the power supply amp chips, voltages all seem to be within reasonable specs...
When I first got it, it would turn on, light up the led's you could play a note and it was like the reverb would stick...then it would start making weird noises and sputtering eventually screeching...now it does nothing at all...the led's do not light anymore even though I am getting ample voltage to them...
It has turned into one of those stubborn "me vs it" situations and is owning my bench...without a schematic its like looking for a specific needle in a needle factory it could be a ton of things...
I have ruled out the power supply because the voltages marked on the board are all correct, all capacitors/resistors are in spec..diodes all check out...
Anyone have any idea where an actual service manual for this might be found?
I have a users manual and found a synth page that has a LOT of roland stuff but just not this mobo...
http://www.synfo.nl/pages/servicemanuals.html#sm
