This is a Dentron Clipperton-L amp I rebuilt for a friend. I recapped it, beefed up the bias circuit, cleaned the t-r relay, and repaired a bad band switch wafer.
The band switch had melted the 15m & 10m contacts, carbon tracked the ceramic wafer, and the heat from arcing had cracked the ceramic. I tried a couple of sources for a replacement band switch, but couldn't get the correct fit. So, I used a dremel tool to cut the rivets from a good wafer and removed the contacts. I did the same to the bad wafer and removed the bad contacts. Then, using a sanding disc, I removed the carbon from the broken pieces of the bad wafer. Next, I re-assembled the wafer with Cyanoacrylate glue and accelerator. Using small machine screws and nuts, I re-installed the new contacts on the wafer, and reassembled the band switch.
I recapped with 105° C electrolytics. It required redrilling the OEM board, and remapping the lower tracing.
I also padded the pi-net loading circuits to allow the load control to load around 50%, something these seldom do on 160, 80, and 40m.
Now, she's back in the air and burning leaves off of the trees :-) Here's a few pics:
