Hi Gang!
A quick update on the Argosy II project.
After more tests and a few experiments, I concluded that the PA was in
fact only running on one output transistor.
I would rather pick fly poop out of pepper than dig into a solid state
PA, but that's what had to be done.
As it turned out, one of the finals had a collector to emitter error.
While not a complete short, there was about 2k worth of resistance
between the two leads.
The other one tested just fine.
However!!
As you may or may not know, the finals used in the Argosy series are
no longer made. The MRF477 are just gone. I called RF parts and they
had one pair left...at $90 ( I did not ask if that was for the pair or
for just one)
There's three avenues
1. MRF479 A bit less power, and $26 each
2. MRF497 A bit more power and $40 each
3. Leave it as is and run with just one PA transistor.
I chose door number 1 and will have the new parts in house sometime
next week.
The story continues...
Mike, WB8VGE
SunLight Energy Systems
The Heathkit Shop
http://www.theheathkitshop.com/
J e e p
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A man with one clock knows what time it is. A man with two clocks is
never sure.
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