Since it had worked wonders on removing the remaining background noise on my Cembalet N, I decided to replace all the resistors on my Pianet N (version II). I recapped the Pianet when I got it a few months back, but it seemed that the hiss and static was increasing a bit, so I thought I'd be able to take care of it by replacing the reistors. Well, I plugged it after replacing the resistors to be greeted with a loud hum. Shut it off, removed the lid, and smelled a distinct burning smell...but no sign of anything burnt. The only problem seemed to be that the ground pin on the volume pedal socket broke off. Reconnected that again, turned it on again, this time with the lid off. Everything working fine. Replaced the lid. The hum was back, so I figured that the lid must be shorting something out. The only thing that looked like it would be touching the lid was the metal case of one of the transistors. Moved that out of the way, replaced the lid, everything worked fine again.
...Except the vibrato depth was weak. So I went back in to tweak the vibrato depth level, and as I adjusted it one way, the bulb started to slowly dim out, and the power for the entire Pianet shut off too. The fuse blew - easily replaced, as I had a direct replacement lying around. Turned it on again, played well for about 10 seconds, and the bulb began to dim out as the sound faded out to be replaced by a hum. Shut it off and turned it back on again two more times, same thing. Although the third time I took the bulb out to see if that would change anything - it didn't. The fourth time I powered it back up, I got nothing at all.
After letting it sit for a few minutes, I tried it again. This time it worked for about a minute before fading out, fading back in, and ultimately fading completely out again. The unit is still getting power, because the mains light stays on even after the sound disappears.
Any ideas what I should be looking for to bring it back to life? I guess the moral of today's story is to just deal with the hiss...