Anyone have any experience with the Eico Stereo 40? I have one with one channel no audio. it is the channel with V4 and friends. I've done several voltage checks and their isn't much difference. Is their something common in this device that kills audio in one channel? The other channel works fine and sounds good. When I put my meter probe tip on the good channel, I hear scratching, on the same spot in the other channel, nothing at all. My next step will be to try and inject a signal but I need to dig up the tools for that first.
Thanks!!
Thanks!!
Balance check switch or low filter switch if C30 bad?
Make sure you 're not plugged into the center channel instead of the left I think it is?
I have a ST-70 and had to do a lot of work on it; sockets, capacitors, resistors, selector switch, bias pots.
Make sure you 're not plugged into the center channel instead of the left I think it is?
I have a ST-70 and had to do a lot of work on it; sockets, capacitors, resistors, selector switch, bias pots.
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I have an ST70 as well and one channel was dead. I found the cathode resistor on the output tubes had gone open. Replaced it and it was back in business.
If you have one working channel and one that isn't, it is easy to take measurements to determine where the fault is. Start measuring resistance (amp off) and voltages (amp on). There has to be a difference somewhere.
Yeah I have been comparing channels. Not much difference between the two. I figure a dead cathode resistor would throw voltages way off. I was wondering if it has something to do with the weird speaker connections it has. The next chance I have to look at it will be Wednesday. I will try and inject a tone and see where I lose it. Deathrex suggested looking at a switch in the low cut filter and it's capacitor, I'll look at it too. I think the gain stages are OK, I think it is an interrupted path.
One thing I can say about this thing. It really is a rats nest of wires. I really cannot imagine Morgan Jones doing this layout!
I had to replace a makeshift power supply cap with something close to the proper can style and I bypassed the GZ34 with some silicon and a pair of 40 Ohm resistors. I left the GZ34 in place just for looks! If I planned to keep this thing I'd change one more PS cap. It goes about 15 volts above its rated voltage during warm up, then drops to well below its rating during operation.
I had to replace a makeshift power supply cap with something close to the proper can style and I bypassed the GZ34 with some silicon and a pair of 40 Ohm resistors. I left the GZ34 in place just for looks! If I planned to keep this thing I'd change one more PS cap. It goes about 15 volts above its rated voltage during warm up, then drops to well below its rating during operation.
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