I wish people would read service manuals when they are available. The PSU is not "very under-engineered". It errs on the cheap side for foolproof protection and noise filtering, but it's an OK PSU otherwise. Besides you can't really expect the manufacturer to protect its hardware against user modifications...HideawayStudio wrote:My PSU failed in exactly the same way as yours - it's very under-engineered and it seems Kawai made a poor choice of fuse rating and rather than just taking out the fuse it takes out the chopper transistor in the SMPSU as well.
If you had actually derived the +5V from the LCD power block instead of tapping into the floppy or someplace else, this would have been avoided. The LCD powerblock is protected by a thermistor that would have likely tripped upon short:
I just replaced my dying original LCD by a "blackline" double FSTN LCD (blackline is the new cool blue) which I got there, very nice displays: http://www.artronic.com.pl/o_produkcie.php?id=775 (this guy has an eBay store - in english
), and it required zero modification (all pins connected). I powered the A/K pins (LED backlighting) from C14 on the PSU, which is the input capacitor to the inverter stage, and it comes after the thermistor. Rather than desoldering Q3, I chose the somewhat more drastic option to cut the PCB track between C14 "+" and Q3's Collector. If I ever want to go back to EL lighting, I can drop a bit of solder and back it is: no component lost.I've noticed someone mentioned the Wavestation A/D in the thread: these LCDs do work there too (I've replaced mine with a black on white), but there's a bit of modification to do for contrast adjustment, as explained here: http://www.tellun.com/wavestation/wavestation.html
Anyway, here's the result, it fits really well with the black border:
).