FM broadcast transmitter repair

Thread Starter

Mooks

Joined Nov 27, 2016
10
Yes :). I was thinking of the MRF314, but it wouldn't hurt if you posted the DC voltages (Vbe, Vce) of all three transistors. RF off is possible.
OK. ,may take me a day or two to get that done. The MRF314 is easy, the others will take some work.
Mike
 

Thread Starter

Mooks

Joined Nov 27, 2016
10
Here are the voltages for the MRF314 without RF ( removed the power suppy to the driver board).
Base 0.313 volts DC
Emitter 0.03 mv
Collector 26.927 volts DC.

I am just leaving home for about 2 weeks and won't be able to do any more testing until I get back.
Will then work on the other 2 transistor voltages.
mike
 

Thread Starter

Mooks

Joined Nov 27, 2016
10
OK , here are the voltages that I measured

MRF314 Base 0.313 V Collector 26.93 V Emitter 0,03V

2N4427 Base - 0.15 V Collector 14.67 V Emitter 0.22V

KSP10 Base 0.84 V Collector 14.78 V Emitter 0.39V

all measurements with respect to ground.

I am going to be away from home for a couple of weeks and won't be able to do any measurements till I get back.

tnx
Mike
 

drc_567

Joined Dec 29, 2008
1,156
... Looking at the 2N4427, there might be a problem. Those base-emitter voltages indicate that the transistor is turned off - no amplification.
 
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