On The Bench Today: ANOTHER FUCKING KEYBOARD...?
(SNIP)
A quick once-over shows no major surprises; I see a few ring cracks on the KB PCB (yup, single-sided Paxolin ) that will need the solder touched up, and I suppose I might go over the main PCB with my MS8911 and make sure there are no egregiously compromised electrolytic caps. If the thing acts in any way odd, I'll probably shotgun them all.
I'll stop back with more pics once it's all done... unless the current topic has shifted to something else much more interesting.
Musicians and coffee. Who'd have guessed...?
Disassembly of the rear connector assembly was pretty uneventful... just a few joints to desolder.
Wait...
The 5.5 DC power jack is not just captive in the panel, but is actually integrated into it?
YAMAHA, you BASTARDS!!!A quick rummage through my junk bin revealed no one-piece power jacks which match the footprint of this bastard child... same with a quick look on fleaBay and slAmazon. I did however find a 10-pack of panel-mount 5.5mm power jacks for $8... In the cart they go, along with some household crap to make the minimum for free next-day, and back to the bench.
Here is where the MS8911 shines; working your way through a PCB looking for obviously bad caps. The 0.1V signal setting means you almost always get a meaningful result on both capacitance and ESR, and while it does take a half a second longer to settle on a number, overall it saves a lot of time vs going back and retesting when you get a reading that's way out to lunch.
A'aight... there's a lot more cleaning to do before I can start reassembling everything but the mainboard. That's mostly domestic-type work I won't bore you with unless I happen to find a crunchy snack... err, interesting resident.
mnem