Re: #bitx40 Q8/Q9 dead - no TX or RX #bitx40
Actually, not much need to remove Q7,Q9,Q9 if doing the quick fix.toggle quoted messageShow quoted text
Remove R70, short across C71 to ground T2-1,
cut the trace from Q7 to T2-6,
then add Farhan's 4 resistor network between Raduino and T2-6.
Removing 12v from the LM78L09 at U2 might save a few milliamps.
But again, you may have a bunch of other issues to chase once this is cleared up.
Evan is right, a grounded DDS1 would give the symptoms you describe.
Base goes to ground, and so does everything else around Q8 and Q9.
But DDS1 has a series cap on the Raduino, so a short on the DDS1 signal
would almost have to be a problem with the DDS1 wiring harness.
On Thu, Sep 17, 2020 at 07:00 PM, Jerry Gaffke wrote:
A possible quick fix: remove Q7, Q8, Q9.