Conrad Johnson PV-10a hum. Any advice?

[cchean]

Hello Folks,

I have a CJ PV-10a preamp that has a loud hum. It is constant and present in all source inputs. I am thinking it needs a recap job done or maybe a voltage regulator replaced. Am I in the right direction? Does anyone have the service manual or schematics for this preamp? Thanks.

Carlos

 

[SY]

Both channels or just one?

Have you swapped out tubes?

 

[cchean]

Both channels. No, I have not tried anything yet.

 

[Palustris]

I think you could be correct about the voltage reg. I would send it back to cj for refurb. and updating. They are reasonably priced, quick and very professional. I have sent back both my PV4 and PV5 to cj at one time or another.

 

[SY]

Both channels. No, I have not tried anything yet.

Two possibilities: a ground has come loose or the power supply is fritzed. I'd trace the ground circuits carefully, and make sure everything is still well-connected. Especially true at connectors, screws, lugs, stuff like that.