Ok. Swapped all of the op amps, powering up and testing each time. Same exact results every time. So definitely not the op amps. Swapped a few transistors and got the same results too. Hmmm... Any other thoughts here? Still have a "click" for kick and mid tom and no life at all out of the high tom. All the IC's, op amps and transistors are socketed, so they're relatively easy to swap. Thinking it might be deeper than that. I'd really appreciate any insight!

Yeah, as I found out, there's no use swapping op amps if there's nothing being fed into them.

I don't know anything about electronics but I borrowed an oscilloscope and poked around to see how far the signals got before they disappeared. You'll need the schematics.

I managed to find a missing solder joint (d'oh!) but never solved my dead hi-hat issue. I'm told my next step should be to use the silkscreen & trace diagrams to check the continuity of all traces for the affected instruments.

The original 909 service manual may be of help decoding what your kick drum transistors should be doing, but again, you'll need an oscilloscope. Raf's 909 circuit analysis is quite useful too.

First of all D-wreck, thanks so much for actually replying! I busted out the oscilloscope and took a crack at it. I checked out the schematic and tried my best. It seemed like I got good readings for the trigger... But I'm guessing that wasn't a problem anyway since I could hear a click from the outputs the whole time. I think I'm just too much of a noob to really know what I'm looking for to even see the signal of the oscillators for the kick.

This is a meticulous build with very a very clean solder job. Anybody with good (deeper) troubleshooting abilities on here want to make probably the easiest $200 you'll ever make? LOL. I'm sure there's probably just one or two components on each instrument (kick, mid tom and high tom) that aren't working. And everything else is working 100% perfect.

I'd be willing to ship my build to someone to troubleshoot and fix for $200 if anybody would be interested. I'll include a return label, so all you'll have to do is call UPS and schedule a pickup or drop it at a UPS store when it's done. I REALLY wish I was able to figure it out on my own, but I just don't have any more time to spend (it took a pretty long time to build, after all ). I really hope someone can help me out!

Hi,

Just saw your post about Nava repair, I can take a look if you're interested, but I'm located in France. If you're in the US maybe it's better if you find someone here (less shipping fees and import charges). Anyway, I would be happy to help getting this Nava sound as it should

Have a good day,
Best,

Bastien

Hey Bastien! Thanks so much for the offer! I'm going to try to find somebody in the U.S. if possible first, but if I can't find anybody, I might take you up on that!