Bob, Just recently, the right front tube was not powering up. A slight jiggle and the rectifier flashed, fuse then blew. Replaced the rectifier and new EL34, ran fine for 2 days. Now the same right front tube is not powering up again. thoughts?
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Brap- Posts : 234
Join date : 2013-11-28
Age : 69
Location : Plainfield, illinois
Bob Latino- Admin
- Posts : 3276
Join date : 2008-11-26
Location : Massachusetts
Brap wrote:Bob, Just recently, the right front tube was not powering up. A slight jiggle and the rectifier flashed, fuse then blew. Replaced the rectifier and new EL34, ran fine for 2 days. Now the same right front tube is not powering up again. thoughts?
The best two ideas are that the tube socket pins are dirty or you have a bad solder connection on that tube socket. Try cleaning the tube pins and the socket pins FIRST because this is the most likely problem.
Bob
Brap- Posts : 234
Join date : 2013-11-28
Age : 69
Location : Plainfield, illinois
Thanks Bob -- strange it has been working just fine for over a year!. Will try that first, then go through the section on measurements wihout tubes, etc afterwards all over again.
Roy- Posts : 177
Join date : 2018-01-14
Location : Netherlands, Europe
Also perhaps check to see the tolerances of the socket hmm - failing to come up with the english word for it here - the springy metal pins/ leaves that grab the tube pins in the socket - some of the pins get hot and with age and tube rolling this may relax the female pins ( is that the word? ) to the point where they are not grabbing the pin from the tube much at all and things go amiss
Kentley- Posts : 496
Join date : 2015-03-06
Age : 72
Location : Worcester, MA
We like to call the process "retensioning the sockets", Roy. It is pretty easy to do with a very small jeweler's screwdriver, or, better, with a flexible surgical probe. Just take care not to bend the metal more than a tiny bit.
Oh, and most tube sockets have tiny spaces around each pin hole for just this purpose.
Oh, and most tube sockets have tiny spaces around each pin hole for just this purpose.