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QCX new build resolved transmit issue but I hear only noise when listening across the band #qcx #antenna

Fast hosts
 

Hi
I had very welcome help in sorting out a lack of any RF output from the group on my QCX and self test now shows a good 4.5 watts measured. However I have no signal on receive. using my long wire antenna on a £5 Pixie CW transceiver I can hear CW across the band but when same antenna is connected to the newly built QCX I hear nothing but hiss.. no birdies or anything. I am looking for the easiest way to troubleshoot the receive path. I do have a DDS function generator so can that be used to inject a signal anywhere and try to trace it? Sorry but i'm a bit lost here. Any key points or components I need to recheck
73 Keith M6OLP

Ronald Taylor
 

Hi Keith. The best way to troubleshoot the receiver section of a QCX is to follow Hans’ very good troubleshooting guide located here:
If you don’t have an oscilloscope, see if you can borrow one as this is the best and fastest way to zero in on the issues.

Good luck .. 73 … Ron


On Sun, Nov 24, 2019 at 12:01 PM Fast hosts <beneagles71@...> wrote:
Hi
I had very welcome help in sorting out a lack of any RF output from the group on my QCX and self test now shows a good 4.5 watts measured. However I have no signal on receive. using my long wire antenna on a £5 Pixie CW transceiver I can hear CW across the band but when same antenna is connected to the newly built QCX I hear nothing but hiss.. no birdies or anything. I am looking for the easiest way to troubleshoot the receive path. I do have a DDS function generator so can that be used to inject a signal anywhere and try to trace it? Sorry but i'm a bit lost here. Any key points or components I need to recheck
73 Keith M6OLP

Fast hosts
 

Thanks Ron but I think I might have resolved it with a dry joint. I will however get my cheap Chinese scope out and work though Hans's guide as he says, it's great for familiarising oneself with the way it's designed
73 Keith

Ronald Taylor
 

Great that you solved it. And yes, it’s always good to learn how something works in the process. 

73... Ron

On Sun, Nov 24, 2019 at 12:43 Fast hosts <beneagles71@...> wrote:
Thanks Ron but I think I might have resolved it with a dry joint. I will however get my cheap Chinese scope out and work though Hans's guide as he says, it's great for familiarising oneself with the way it's designed
73 Keith

Steve in Okinawa
 

I continue to be amazed at how hot the receiver is. I heard a very strong OK7 near the end of the contest on 40 and thought conditions might allow a QRP contact, but no go. Turned on the IC-7300, heard the same station only S7 and worked him with 100 watts. Went back to the QCX and he was still blasting in.  JS6TMW