[ICOM] Re: IC781 Power Supply

[mel martin]

>The PSU was designed for the Japanese 100V mains supply. When fed from 120V
mains, the shunt-regulator dissipation increases by a whopping 44%!

Hi Adam...

A while back someone actually ran temperature tests on the 781 power supply.
I think the data was on this reflector... At least a link to it. I
distinctly remember that the rise in ambient temperature with a 120V mains
supply as opposed to a 100V supply was trivial. The obvious conclusion is
that the mains supply not is not the issue... The power supply also ran far
too hot at 100V... So all those 781s out there running on Variacs are at
risk. What is needed is additional cool air. I use the Sherwood Engineering
kit... And it works very well.

I wish I still had the reference. Perhaps someone can provide it.