[Heathkit] HP13 DC power supply question.

[JJ HO]

Dear Green lovers,

I picked a PS along with a junky HW22A at local swapmeet.
They have been restored to a reasonable condition.  However
I noticed the PNP power transistors in the HP13 appeared
unbalanced, i.e., one was warmer than the other one.  Does
any have the spec of the device (Heathkit P/N is 417-60, made
by Motorola, P/N was smeared).  I am thinking about changing
to a pair of MJ2955 or other switching power transistors.

The PS put out correct voltages (800V, 310V, and 100V).
However, this PS generates annoying 1.5KHz audio noise from the
transformer.  I wonder if this is normal.

Thanks and 73,

Jonathan