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Re: JCM 800 pre-volume puzzled

6/8/2004 10:19 AM
Greg	Re: JCM 800 pre-volume puzzled Bruce, Thanks for the help. I noticed strange voltages on v1b cathode during the dead area sweep of gain pot, sure enough, moving the wire from v1b grid to gain pot caused changes in these readings. The fix, simple as re-routing this wire. I had checked signal routing for problems on initial power-up but didn't think to check with amp at various settings. Thanks again, the best thing to do is live and learn and sometimes ask and receive good help. Thanks, Greg

6/8/2004 10:19 AM

Greg

Re: JCM 800 pre-volume puzzled

Bruce,
Thanks for the help.

I noticed strange voltages on v1b cathode during the dead area sweep of gain pot, sure enough, moving the wire from v1b grid to gain pot caused changes in these readings. The fix, simple as re-routing this wire.

I had checked signal routing for problems on initial power-up but didn't think to check with amp at various settings.

Thanks again, the best thing to do is live and learn and sometimes ask and receive good help.

Thanks,
Greg