[Hammarlund] Hammarlund] HX-500 LV choke

[Dave W5QWX]

Hi Jeff,
I would suggest measuring the LV current thru the choke before replacing it out of hand.

I had that same experience with an old NC-183D receiver sometime back. I finally got things
under control (cool running choke and transformer). The old RX had lots of leaky caps, filter
and bypasses along with out of tolerance resistors. By measuring the current and voltage thru
the choke it was found the LV was about 40-50 volts high and the current was 180 mils, which
is way too much for the old beast. Even after changing the bad caps and resistors, the voltage
was still high causing the current to also remain higher than normal. All the RX specs were made
assuming a 110-115 VAC line voltage. My average line voltage here was 122 vac. After first solid 
stating the power supply and installing a bucking transformer and using the filament tap from the 
old rectifier tube, the voltage came into specs and the current thru the choke was down to 117 mils.
Now the beast runs cool and still works great.
Hope you can solve your HX-500 problem with out having to replace a choke that may only have 
too much current pulled thru it from other causes.

Best to you on getting it sorted out.
73,
Dave de W5QWX