Does anyone out there understand how the bias is applied in a Titan? I'm
still trying to get a Titan I bought recently to work. Grid current reads
zero even though it clearly isn't (1000W out) and plate current reads 300m
even in standby. I think I'm not getting any bias to the cathodes. So where
does the bias come from? I think the purpose of the bias board is to take the
bias down from 28V to 8V during operate based on complicated logic there for
QSK and protection. But where does the 28V come from? Is the B- line
supposed to be 28V above ground coming from the power supply? That's my
theory: the B- line is 28V off ground courtesy of the 6.8K resistor, R7, in
the power supply. But I'm theorizing. I would have felt pretty good about
the theory if R7 were open (it's not) or if I understoond what D13 in the
power supply is there for.
I hope someone out there understands this beast well enough to give me some
pointers.
Thanks to all of you who gave me earlier advice. I tried it all including
putting an RF suppressor on the cables going to the meter board.
Jon, K6JEK
--
FAQ on WWW: http://www.contesting.com/tentecfaq.htm
Submissions: tentec@contesting.com
Administrative requests: tentec-REQUEST@contesting.com
Problems: owner-tentec@contesting.com
Search: http://www.contesting.com/km9p/search.htm
|