Sunday, March 1, 2009

A summary of mistakes

I made a whole lot of mistakes when I was putting this amp together. The amp still doesn't work, and I wonder if one of these early mistakes has something to do with that.

The biggest/most-work-intensive-to-fix mistake I made was putting the tube sockets in wrong. The pins on each tube are numbered, so I assumed I could just put the sockets in whichever way I wanted (it can only go in two ways). I could then line the tubes up, decide which hole on the socket I wanted to line up with pin 1, and solder everything on. That's what I did. After sodlering everything I found out that things don't work that way at all. Each socket and tube have a registration tab of sorts. Each tube will only fit into the socket one way. I had wired the 5Y3GT one pin off and the 6V6 completely backwards with respect to the registration tab. To correct this problem I took a dremel tool and sanded off the registraion tab from the tubes. Without that tab the tubes go into the socket in anyway I want. The downside to this is that I would have to sand any future tubes the same way. Here are some pictures to document this mistake:

With all of the problems I'm having now I wonder if either the sanding or some part of incorrect tube installation is causing my OT problems. I don't have a tube tester to see if the 6V6 tube is screwed up. I went back and fixed the tube sockects and resoldered all connections to be in sync with the registraion tab.