Here's a quick tone test after servicing my 1967 U305R Fatboy. This amp was cutting out and popping at high volumes. Turned out to be a very dirty reverb adjustment pot causing the noise. I also serviced the non-working tremolo. This thing sounds fantastic now.
Also, for this video, I had the channels jumpered, so that's why you'll see me messing with both channels' controls.
If interested in seeing pics of the amp and gut shots of the service, go to Guitologist.com.