[Hallicrafters] HT37 SSB

[Paul Galpin]

For those who didn't know, the transformer problem with the HT37 is insulation breakdown between the 5V winding for the HV
rectifier, and other windings. These transformers are now half-a-century (or more) old and beyond any imaginable design life span!
If you decide to wait till the breakdown occurs, then get ready for a complete transformer re-build, at some expense.

The answer is to disconnect the heater connections from the rectifier valve base, let them float where they will.  Replace the
rectifier valve with SS instead. This also gives a slight power increase due to the increased HT volts.

This, of course, refers to the PA final HT. The lower voltage HT doesn't seem to give any trouble that I've heard of, but the same
treatment couldn't do any harm, I hope.

Paul Galpin