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R111 is indeed very hot. ?When testing it I touched it and was surprised how hot it was.

I'm guessing R111 is shot. ? A 1206 resistor is good for about 0.125 Watt. ?If R111 is still good then it is disspating (12v-0.7v-1.6v)**2/100 = 0.94 Watts. ?As you say, it would be very hot if

Michael Thanks, I have the other posts since Jan. Randy, K7AGE

if the resistor is open, perhaps we can solder lead type across the pads even without removing the smd. all the best sarma vu3zmv wrote: -- Regards Sarma

R111 must be hot, if not then it may be bad. Switch off power and then check R111 on the ohm meter. If it is fine then LM386 is gone.

Thanks Jerry. ?I'll see what I can do to get a new resistor in there and hopefully that will bring everything back. ?I'll update this thread once I know for sure. ?Then we can use this knowledge to

OK, then R111 is shot. ?Possibly a bad solder job there. ?Or a fracture, a hairline crack can be impossible to see.? Possible that it blew for a reason, such as a short to ground at U1-6. ?That's

Getting approximately 12 volts on both sides. ?Actually a little over 12 volts on one side, and a little under 12 on the other side. ?The voltage on the diode side of R111 is 12 volts, and on the

Looks like Raj figured this one out, a blown D18. ?AMeasure the voltage from ground to both sides of D18, the side going to R111 and R113 will probably be nothing like 12v ?(more like 1.6v)

The highest voltage I am getting on any of the pins is a little over 1 volt. ?I am getting 1 volt on pins 1,2,4. ?I am getting 1.6 volts on pin 6, and nothing on pins 3,5,7,8

I mean at pin 6 of LM386 which is the audio amplifier.

It should be near/about 12V. In my board D18 blew and I had to put in a higher current diode. 73 Raj vu2zap

U1 which is actually an 8pin LM385/6 amplifier, is not in the RF section as far as I can tell. ?It seems to be the an audio amplifier for the speaker. ?Perhaps I'm wrong, but that's what it seems to

RF stages of oscillators will show weird voltages unless the oscillator is stopped. Short X5 and take readings, I am guessing they will be fine.

All my voltages on the transistors seem to be in line with what Randy was seeing +/- a little bit due to different voltage from the power supply, but close enough to determine that they are probably

Randy, I Just got a message from a member that R136 is supposed to be set so that you get the 1 amp drive with the long hello into the mic. I assumed it was preset and never touched it. He said

For the shipping database. Ordered on 3/18/2017 Shipped on 3/22/2017 Received on 4/4/2017 Board is marked n3_722 checkmark Firing up the soldering iron right now. Can't wait to test it and play

Tim This doc was created by Randy Hall. You should join groups.io if you aren't a member /g/BITX20/attachment/21621/0/BITX40%20Voltage%20Measurments.pdf Art Sent from my iPhone

Ok, I might have found it. ?q16 is showing very low voltage on the Collector. ?The other transistors show -5 to -6 volts on the collector, Q16 shows -.718. ?So that might be something. ?BUT, Q10

Only Q7 works as an amplifier. Q8 and Q9 are emitter followers, so no gain there. -- Ion VA3NOI