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Old September 21st 07, 01:08 AM posted to rec.radio.cb,rec.radio.amateur.equipment,rec.radio.amateur.homebrew
Telstar Electronics Telstar Electronics is offline
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First recorded activity by RadioBanter: Jul 2006
Posts: 985
Default What happened to the SkyWave 2879ABTC?

On Sep 20, 3:03 pm, wrote:
Oh...your bias is magical? It uses no components for compensation?
I always suspected your design to be that of an imaginary nature.


Not magical... it used the base-emitter voltage drop of an MJE3055T
(mounted directly to heat sink) to track with the 2SC2879 power
transistors. Since it used a transistor with gain... it worked so much
better than just a plain old diode on the sink for tracking. It worked
fantastic... I was able to set set class AB bias ( I chose about
200Ma) on the power transistors... and hold +/-5% collector current
changes from -40 to +100C heat sink temp during amp operation.
www.telstar-electronics.com