invalidbuffa
Super Member
I'm working on a 2040 and I can't for the life of me determine why the chassis is hot. I checked the ESR on the filter caps and everything looked fine, and I couldn't see any obvious problems that would cause the issue. The chassis has more potential when the unit is plugged in 'backwards' as in the prong that first goes to the fuse and switch is plugged into neutral.
The other problem is when I turn the unit on, there's no wait for the protection relay to energize the amplifier and it produces a big scary pop as soon as the power switch is pressed.
I don't know if this is relevant but at one point while I was working on it I had the dial face lamp assembly removed, and the two connectors that went to it touched while it was energized. It blew the 3A fuse and killed the diode at D912 (shorted)...I replaced the diode with a 1N4004.
So far I've performed the following work on the receiver:
I replaced the "death" RF capacitor across the power switch with a X/Y safety cap
Replaced diode at D912 with 1N4004
Replaced lamps in tuner face and pointer
Adjusted DC offset and idle current to manufacturer spec
Any ideas that could help me troubleshoot the problem are appreciated, thanks.
The other problem is when I turn the unit on, there's no wait for the protection relay to energize the amplifier and it produces a big scary pop as soon as the power switch is pressed.
I don't know if this is relevant but at one point while I was working on it I had the dial face lamp assembly removed, and the two connectors that went to it touched while it was energized. It blew the 3A fuse and killed the diode at D912 (shorted)...I replaced the diode with a 1N4004.
So far I've performed the following work on the receiver:
I replaced the "death" RF capacitor across the power switch with a X/Y safety cap
Replaced diode at D912 with 1N4004
Replaced lamps in tuner face and pointer
Adjusted DC offset and idle current to manufacturer spec
Any ideas that could help me troubleshoot the problem are appreciated, thanks.
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