[Hallicrafters] Use of 6146B tubes in the HT37

[Mark Shaum]

" When I pulled the finals, one was a 6146, the other a
6146B."


Ugh.  In general this is not a good situation.  I responded in some
detail to Joe on my use of B's and W's in Hallicrafters rigs with no
real issues to report.  But I do NOT recommend pairing up an A with a B
(later mfg W's are the same as B's).  The internal capacitances are
different enough to cause some serious load imbalances with RF pumping
through even if the bias adjustment and resting plate currents seem
shared ok.

Not to say it never works, or can't work, I just want to point out that
there is a possibility for imbalance and shortened tube life if you
"mix" instead of "match".

73! Mark K9TR