Re: WSPR no longer transmitting #wspr #40m

Mike Easterbrook

Always good to check your measuring equipment.  Not suggesting that this is the source of your problem!  But I struggled for several hours with a zero output QCX only to find eventually that my SWR/Power meter was switched to VHF range.  Stupid thing is that I've done the same thing again a few times since (failing short term memory)  Fortunately I now normally remember before getting the soldering iron out.

Along similar lines, I was shocked one day to check the input power to the QCX (nominally 13.8V) and get a reading of 19+ on my DVM.  Eventually noticed the "low bat" indicator and all was well - a few worrying moments nevertheless. 

On Sat, Dec 19, 2020 at 8:35 AM Al Holt <grovekid2@...> wrote:
Were you ever able to see any RF output on your SWR meter? I'm guessing so, but I want to verify that with you. If so, do you have an idea of how much power you were getting out?

I'd recommend not transmitting WSPR, just key the QCX and transmit into a dummy load. 

One idea I have is remove the nut and washer on the PA assembly to see if only one of the transistors is getting hot as well as seeing how long it takes to get hot. Maybe it's just one bad BS170?

The fact that you're drawing 500mA on transmit doesn't seem all that bad. But, no RF out is bad and I'm not sure at the moment exactly the best way or where to start looking.

Again try researching the forum for QCX transmit problems. I'll put on my thinking cap....



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