[Elecraft] K2 RF Q6 2SC5739 too hot
Lennart
lennart at sm6knl.se
Sat Nov 22 09:09:16 EST 2008
My Driver Q6 has too high voltage on the emitter, 0.42 volts instead of
0.23-0.30 volts. It gets very warm and current through it kept increasing
until I lifted it off the PCB and installed a separate cooler on it. Now
current is stable (and I constantly get very good audio reports on SSB.)
Transmit current on SSB no audio is 0.60 amp.
Can I reduce the drive current through R47-R48 adjustments, or should I
suspects something to be broken? Q6 base is 1.075 volts which is normal.
Seems like the 2SC5739 has too high gain?
Regards,
Lennart - SM6KNL
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