HP23 PC boards UPDATE

[mike bryce]

Hola!

Well prototype boards arrived the other day and one has been assembled. It
works

But there are a few things that I want to improve on before doing a final
run.

Here's the poop!

Bleeder resistors get hot. Heath uses 2 watt devices, I used 3 watt in the
prototype. I may go to 5 watt resistors.

The screen (+300) regulator works ok.. However the filter voltage sits
around +360 volts. With the regulator setting at 300 volts, the transistor
must drop the 60 volts. At 100 ma, that's 6 watts. That's hot!

Also, if you were to short out the +300 volt supply, it would take out the
transistor. Those are expensive so I will put a current feedback loop to
protect the transistor.

I have posted photographs of the prototype supply on the web site

http://www.theheathkitshop.com

just follow the link.
--
Mike Bryce WB8VGE
SunLight Energy Systems
"Electricity at the speed of light"

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