Hi everyone,
Recently, I've purchased a secondhand but defect A15 madamp.
Now, I'm a newbie in working on amps, but I've wired guitars etc and I feel confident enough to work on an amp.
I've done some research and I've read that in most cases, you'll have to drain the filter capacitors (using a jumper wire with a resistor, or just a resistor, using one hand and the other arm behind your back) by, if I remember well, connecting the positive end of the capacitor to ground(I'm just remembering stuff now, so don't shoot me if this contains some mistakes) untill the voltage drops to zero.
Now I've read the madamp manual, and in there, there's only told that the amp contains high voltages, and there's nowhere explained how to drain these capacitors, maybe I've missed it when reading.(I've found a part when you put a voltmeter somewhere and then watch the voltage to go down to zero, so I thought, this is it, but I'd rather check it here just to be sure) But i've read somewhere else that in some amps, these voltages drop automatically/spontaneaously to zero after you haven't used them a while. So, I conclude that this is the case with these A15, so that the voltage drops down automatically...am I right? And when you drain these caps, I suppose you shoud pull out the connector to the wall outlet first, or not? And do the speakers should be connected to the amp then too or not? These questions are the things that hold me back to start the work, since I don't want to be fried but I do want to do it by myself. First I wanted to buy a new kit, but I thought... secondhand and broken, I could build it again so it's almost the same experience. To most of you guys this maybe should sound like a dump question about something rather basic, but anyway, I'd like to know;D.
About the broken amp itself, the previous owner told me that everything went wrong after he's installed the footswitch. So I'll have to bring the amp to it's original state, so without the footswitsh, and then test it. And then try to install the footswitch again, but doing a bit more cairfully. And checking for things that contact ground when they aren't supposed to. And afterwards testing offcourse.
Now, sorry for the long post:) but I tried to explain it decent the first time. For people who like to help me, answers in german are also welcome. I understand it(=German language, I'm Belgian btw) but it's been too long that I've followed classes German (language)(and English too) so I thought English would be better for this one:)