Thread: UHF (70cm) PA
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Old January 19th 09, 10:13 PM posted to rec.radio.amateur.homebrew
raypsi raypsi is offline
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First recorded activity by RadioBanter: Jul 2008
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Default UHF (70cm) PA

On Jan 19, 1:00*am, Bob wrote:
BV wrote:
P.S. It's a linear amp i want to build


73 de OZ1BV, Brian


A bit of advice:

..........a circuit without DC bias. *The Vbe max
is only 4 Volts, which gives a useful hint!

Hey OM,

I don't thin so. The hint should be the input impedence is like less
than 1 ohm. And although you may state that Vbe max is 4, that may
apply in class C but not say class AB where the all yoiu will be doing
is varying the current thru the base and the voltage will swing next
to nothing, like a base swing current of 10 or more amps into the base
impendence.

So you can't find a good schematic for a linear, I suggest you get a
good spice program, and a really big smith chart.

I wouldn't use teflon board of any kind, when teflon burns it turns to
mustard gas.

73 OM

n8zu