Conrad Johnson PV-1 schematics

[dudette]

I have searched high and low on the www and the closest I have come is a schematic for a PV2. Does anyone know where I can acquire a Conrad Johnson PV1 preamplifier diagram? The "minty" (Oh, how I hate that description) preamp I just purchased on "FeeBay" turned out to be full of hum.

Thank you for any assistance in this regard.

[dudette]

Originally Posted by dudette

I have searched high and low on the www and the closest I have come is a schematic for a PV2. Does anyone know where I can acquire a Conrad Johnson PV1 preamplifier diagram? The "minty" (Oh, how I hate that description) preamp I just purchased on "FeeBay" turned out to be full of hum.

Thank you for any assistance in this regard.

I wrote to the company and they were kind enough to provide what I needed.

[camusmuse]

In the same boat, have had a PV-1 for years. Pulled it out of storage( after several years) and now has hum independent of volume.

Does your unit have the rack mount face or the regular "short" one?

Nathan

[dudette]

Originally Posted by camusmuse

In the same boat, have had a PV-1 for years. Pulled it out of storage( after several years) and now has hum independent of volume.

Does your unit have the rack mount face or the regular "short" one?

Nathan

It is a rack mount with serial number in the latter part of the 1700s. I am surprised that the capacitors are failing after 32 years. CJ was supposed to use only the best in parts but I have amps and radios that are twice as old with original caps and they work like the day they came off the production line. Even back then, you could acquire components that were built for longevity. Only problem is that if you built them too well, no one would ever return them for servicing.

[computerwala]

I suspect that the Capacitors decayed due to the excessive heat produced by the tubes. These units are enclosed and have poor ventilation, which leads to such component failures. A full PV-1 restoration costs $395 and includes new electrolytic capacitors, diodes and a full power supply restoration too. Takes around four weeks to complete. You can get in touch with us (Amplifier Surgery) if interested.