11-07-2017, 06:29 PM
Jensen 12" Alnico 5 PM Speaker Concert Series. I think this is the original speaker for the Ampeg GuitarAmp. The serial number (605155) indicates amp number 155 manufactured in May 1956 from the information I gathered.
I just replaced lots of caps and a number of resistors. All tubes seem to be original Sylvania, with the exception of the 5Y3-GT rectifier tube, which is labelled Electron Tube, Japan.
Replacing the old caps and drifting resistors cleaned up most of the hum. I get a mild 60 Hz hum now, which disappears twice when I rotate through 360 degrees while holding the guitar. Trying to figure that one out. The guitar must be acting as an antenna. I am still working on the amp, hoping to eliminate that last bit of hum.
Larry
I just replaced lots of caps and a number of resistors. All tubes seem to be original Sylvania, with the exception of the 5Y3-GT rectifier tube, which is labelled Electron Tube, Japan.
Replacing the old caps and drifting resistors cleaned up most of the hum. I get a mild 60 Hz hum now, which disappears twice when I rotate through 360 degrees while holding the guitar. Trying to figure that one out. The guitar must be acting as an antenna. I am still working on the amp, hoping to eliminate that last bit of hum.
Larry