[Heathkit] FW: TT-1A Issues - MORE DETAILS

[Gary H. Harmon, Jr.]

From: Ron Eisenbrey [mailto:ab5wg at satx.rr.com] 
Sent: Wednesday, October 04, 2017 7:02 PM
To: 'Gary H. Harmon, Jr.'
Subject: RE: TT-1A Issues

6V6 tube will not test in the TT-1A.  Multiple tubes, all do not test and
are known to be good.  There is no response from the tester when the gm test
switch is operated.  Other 8 pin tubes test good in the same socket, only
the 6V6 will not respond.  (Perhaps a wrong setting in the tube data?)

12AU7 tube always measures extremely low with the switch settings given in
the tube data.  If I decrease the bias, tube will test good.  This happens
with any 12AU7, all test fine in other testers.  (Again, I suspect something
is wrong in the tube data settings).  Bias is calibrated, as are all other
internal calibrations on the TT-1A.  All other 9 pin tubes test good in the
same socket, just the 12AU7 always tests low.