[pbunn]

I am reworking a National NC 60 that had been revenged in the power supply but otherwise in nice shape. I have redone the power supply and recapped the paper caps . It works some what but has a loud background buzz. It sounds like bad interference, but my ham transceiver with the same antenna does not hear it. It is worse on the AM band.

I have not cleaned the band switch or the tube sockets. Tubes are all NOS 


Any ideas?

Thanks in advance