[Heath] HX-20 alignment problem

[James Owen]

Look at the RF output with a scope as that will tell a lot. If it's bad put the scope on the output of the Balanced modulator buffer tube.  You can look here and adjust balance with the scope also.  If things are distorted here look for ac getting into the circuit somewhere.  Bad filter in PS, cathode to grid leakage in a tube etc.  If the carrier won't balance and especially if no change when adjusting the pot suspect a bad pot. I just had one in a HW12A where the carbon element had a break to  one of the end terminals of the pot.  The scope is your friend and one of the best trouble shooting tools there is.
73 Jim
  James C. Owen, III K4CGY

      From: Alexander N. Gerli <ac1wye at gmail.com>
 To: heathkit at mailman.qth.net 
Cc: heath at puck.nether.net; heathkit at yahoogroups.com
 Sent: Saturday, February 27, 2016 7:51 PM
 Subject: [Heath] HX-20 alignment problem
   
Hi, everyone!  This is going to be a needle-in-a-haystack question, but here goes:

I have a nice HX-20/HR-20 pair. So far, the receiver is great, and I'm trying to align the TX by the Manual. So far, I have the 9MHz IF transformers peaked and the 80m Mixer and Driver coils peaked. Now, I'm trying to get to the carrier null part. I've hit a wall, as when I use the mic PTT and listen for the signal in a monitor RX, the signal sounds AWFUL. It's not a carrier, but a garbled-sounding rough buzz, and this is with no TX audio per the Manual. It should be a decent CW note, but surely not THIS! Makes me think it's self-oscillating, but that's not happening because when I let off the PTT, no signal and the T/R Relay is working as it should, So far, the alignment procedure has gone without a hitch.

Anybody have a guess what might be amiss? I was getting about 40W into my metered dummy load and that's about correct for a single 6146.

​73,​

​Sandy AC1Y​

Alexander N. Gerli, Sr.
548 Allred Mill Road
Mount Airy, NC 27030-2202

Scotsmen walk about 900 miles each year.
A Scotsman drinks around 45 gallons of Whisky a year.
Scotsmen get about 20 Miles Per Gallon.

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