[Hallicrafters] HT-37/32 bias

[wb8jkr at juno.com]

  Bill,

 Have you tried subbing the tubes, or pulling them 
out of the socket and measuring the rec/xmit bias
voltage? I'm starting to wonder if you might have 
one or two bad 6146's drawing excessive grid 
grid current and loading your bias supply.

Mark  WB8JKR

On Sat, 21 Aug 2004 22:45:51 +0600 Bill <k2wh at optonline.net> writes:
> Al,
> 
> You say the -49 volts must be measured in transmit mode.  I assume 
> you
> mean key down RF out.  The service manual on this adjustment does 
> not
> state this.  It states the bias should be set at -49 volts in MOX
> position.  This could be an important clue to my hot tubes since it
> seems this would allow them to cook at -49 volts in receive or 
> standby
> position.  In transmit, the bias would go even lower.
> 
> I did set my bias in the MOX position, but without any RF output 
> simply
> because I had yet to connect a keying circuit.  I will measure this
> tomorrow and report back to all on my results.  Very interesting!  
> BTW,
> I have just
> started a restoration of an HT-32.
> 
> K2WH


________________________________________________________________
The best thing to hit the Internet in years - Juno SpeedBand!
Surf the Web up to FIVE TIMES FASTER!
Only $14.95/ month - visit www.juno.com to sign up today!