"Daremo" bravely wrote to "All" (05 Feb 06 21:13:38)
--- on the heady topic of "Help with Univox Guitar Amp"

Da From: "Daremo"
Da Subject: Help with Univox Guitar Amp
Da Organization: Road Runner High Speed Online http://www.rr.com
Da Xref: core-easynews sci.electronics.repair:357600



Da I have a Univox Amp I purchased off the back of a guy's truck. It
Da powers on, but all I get is a hum output. I attach a microphone or
Da guitar cable to any of the inputs and *nothing* changes the output
Da sound. The volume control doesn't change the level of the hum output
Da either. I should say, I've been around guitars and amps for about 20
Da years and the output of this sounds normal, not necessarily a "hum".
Da It soulds like a normal amp with the input (guitar or mic) turned off.
Da I've tested all transistors with a VOM and they seem OK. I've
Da cleaned all pots/boards contacts with contact cleaner. I do not have
Da a o-scope or a signal generator, so I realize troubleshooting will be
Da difficult. I do have a schematic. My question is this: Do any of you
Da have advice for troubleshooting this with just a voltmeter?


Troubleshooting need not be difficult. Nor do you need a signal
generator or a scope. Simply inject some audio program into an input
and use a small amplifier to trace the audio path in the circuit.
Where the signal stops will be the bad part. Easy as pie!

A*s*i*m*o*v

.... A stereo system is the altar to the god of music.