[Hallicrafters] HT-32A no power out

[Richard Knoppow]

----- Original Message ----- 
From: "K4PRF - Burton Pratt" <pratt at knology.net>
To: <hallicrafters at mailman.qth.net>
Sent: Thursday, March 08, 2012 6:43 PM
Subject: [Hallicrafters] HT-32A no power out


>I finally solved the problem with this HT-32A and learned a 
>valuable
> lesson in the process.  Just because a tube checks good in 
> the checker
> doesn't always mean that it will work in the socket.  I 
> was hard on the
> trail of a bias problem and had failed to check all the 
> heater pins.  In
> this case the heterodyne oscillator and the 2nd mixer were 
> cold.
> Repaired the heater line between the 3rd mixer and the 
> heterodyne osc.
> and she took right off.  Lesson learned is always check 
> the voltage on
> all the pins and not just the ones you suspect are the 
> trouble makers.
>
> Thanks to all who offered help in solving the problem. 
> I'm looking
> forward to getting this rig back on the air.  For 
> Hallicrafters lovers
> the HT-32A and SX-101A make an impressive station.
>
> 73 and thanks
>
> Burt
> K4PRF

      Something else to watch out for is the condition of 
the tube pins and the socket pins.  I had a very frustrating 
problem with a Drake transmitter, where the pin voltages 
were wrong and the thing didn't function. The tube checked 
good. I then measured the socket voltages using a tube 
extender, the thing began to work!  I got suspicious and 
cleaned the tube pins with a wire brush, that fixed it. 
Evidently the sockets in the TX, extender, and tester all 
contacted the pins slightly differently so that in the TX 
there was poor contact.
     A small wire brush works on tube pins (but watch out 
for gold plated ones) and those small brushes sold for 
cleaning between your teeth work well for the sockets when 
used with contact cleaner.


--
Richard Knoppow
Los Angeles
WB6KBL
dickburk at ix.netcom.com