Thread: UHF (70cm) PA
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Old January 19th 09, 10:32 AM posted to rec.radio.amateur.homebrew
BV BV is offline
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First recorded activity by RadioBanter: Jan 2009
Posts: 4
Default UHF (70cm) PA

Hi Tom

Hi Brian,

My Motorola data book says these are designed for class C (e.g. FM)
amplifier service, not linear. *I suppose you should expect to get a
little less PEP power out of them in linear service, for good
linearity.

The Moto data sheet has a test circuit; I could scan it, if it would
be any use to you. *The microstrip dimensions are for glass-teflon
board, er=2.55, 1/16" (1.6mm) thick. *Of course, the test circuit is
for a single transistor, not a pair. *It is solidly class C: *the base
and emitter are both at DC ground.

Cheers,
Tom- Skjul tekst i anførselstegn -

- Vis tekst i anførselstegn -


This is correct, but I found out that Tokyo Hy-Power HL-120U uses
these transistors in this PA. If they are able to make a 100W linear
amp i hope to be able to do the same:-)
(The list where I figured out what transistor type is udes in PA's:
http://www.electronicpool.de/en/funkgeraetetypen.html)

I have not been able to find a schematic for HL-120U. It would be nice
to see how they designed the bias circuit.

Medt 73 de OZ1BV, Brian