Ohm On The Range: Wiring an Ampeg V4 Impedance Switch.

I've had a V4 here for quite a while because the owner was going through some changes, had a hiatus in Maryland for a year or so and is now back in town.

So I dragged it out of storage and got it up and running but it still had one of the original issues from the first time I saw it and that was, no 8 ohm output. 2 and 4 are fine but nix on the 8.

So the issue was either the switch was defective, incorrectly wired, or the output transformer was bad. It looked as if the output transformer was recent. I changed the switch with no improvement.
I spent way too much time researching this without success and in the end, made a trip to Polk City where a friend of mine has a similar amp so I could do an inspection and narrow the issue down.

When I pulled the chassis of Barry's amp out, two things were obvious. First, Ampeg had cut a corner of the chassis out so that the switch could be accessed and inspected without complete disassembly.
Second of all, the link between the second and third row of switch terminals had never been installed-I suspect, by the person who installed the output transformer.

This morning, it was the work of a few minutes to take a bit of wire, make a link, and solder it in place.

The moral of the story is never expect that work previously done was done right. As Reagan said "Trust-but verify. Play-but cut the cards. And never be afraid to see what you see."

I promise, I'll cross post stuff from my FB page in the future so the entire world can see some of the stuff I'm cookin up.