This is more of a BG than a DB question, but (1) it's applicable to DB electronics and (2) when I tried asking on the BG side, I found myself in a crowd of clueless thrashers, one of whom suggested I should ask Ken Smith ;-) So this is directed to fdeck, DURB and our other electronics mavens.
I bought an Olympia acoustic BG with a Fishman Classic 4 preamp a week ago that exhibits a couple of problems:
1. Hum, which goes away when you grab the shield. There's a good signal along with the hum, but I don't know if there's enough gain.
2. When inserting the cord into the endpin jack, as soon as the barrel contacts the ring connection, completing the battery circuit, the power LED flashes and goes out. Removing the cord and reinserting repeats this. I pulled the jack and manually shorted the contacts and got the same effect, so it's not a jack malfunction.
Pulling the preamp out, the wiring appears to be all intact. No visible shorts where the coax attaches.
I don't know what the tolopolgy of the Fishman preamp is, but I'm guessing this might be a shorted cap. One thought was to check the current draw on the battery, which is a bit difficult but can be done.
Any ideas?
(If you're wondering why I bought a BG with electronics problems: It was only $100 with the HSC- how could I resist? That, and the seller didn't tell me about it. He did say "I only play it acoustically" which suggests in retrospect that he knew damn well about it, but it was still a good deal)
I bought an Olympia acoustic BG with a Fishman Classic 4 preamp a week ago that exhibits a couple of problems:
1. Hum, which goes away when you grab the shield. There's a good signal along with the hum, but I don't know if there's enough gain.
2. When inserting the cord into the endpin jack, as soon as the barrel contacts the ring connection, completing the battery circuit, the power LED flashes and goes out. Removing the cord and reinserting repeats this. I pulled the jack and manually shorted the contacts and got the same effect, so it's not a jack malfunction.
Pulling the preamp out, the wiring appears to be all intact. No visible shorts where the coax attaches.
I don't know what the tolopolgy of the Fishman preamp is, but I'm guessing this might be a shorted cap. One thought was to check the current draw on the battery, which is a bit difficult but can be done.
Any ideas?
(If you're wondering why I bought a BG with electronics problems: It was only $100 with the HSC- how could I resist? That, and the seller didn't tell me about it. He did say "I only play it acoustically" which suggests in retrospect that he knew damn well about it, but it was still a good deal)
