90s Fender Super. Needed new screen resistors because of a tube short. Screen resistor blew before the mains fuse did.

Fender Twin Reverb. Silverface era, AA270 — one of the earlier ones, probably 1970ish. In need of some general maintenance. It had a cap job before it came to me, but there are lots of drifted and heat-damaged components throughout the power section, and inexplicably, the bias supply caps are original.

Comparison of the typical Blackface Fender tonestack (blue trace) with the Hiwatt DR tonestack (green trace). The limits are displayed — all combinations of minimum and maximum rotations.

Fender Hot Rod DeVille guts. This one just had an arc from pin 3 to the backside of the grid-stop resistor on one of the power tubes. From the looks of things it was caused by a droplet of some beer-like substance, or maybe an exploding insect. Cleaned up the arc trace and installed new power tubes. The amp had the original Fender/Groove Tubes “6L6B” power tubes, which of course were starting to show their original labels — Sovtek 5881s.