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Hello Eric, Maybe you can try with smaller steps in menu 8.5. Start again with 27.004 and move up or down in steps of 1 kHz, or even smaller and see what happens. If you have the opportunity, check

I had this and found the problem was a slightly less than conservative regulator design on the Si5351A board. The drop out voltage is way too low for the operating point on the LM317LZ so it's

Hi Al, all FYI the presets are 24-turn types. Another thing: make sure gain control is not at minimum. The audio for the unwanted sideband adjustment is taken AFTER the gain control. So if you have

Since you have a 40m QCX you can use CHU on 7850 kHz for calibration if you're short of other test equipment. When you're 'spot on' the QCX will produce a 700 Hz tone. A smart phone with an audio

Mike, It seems unlikely the chip could be reset by a random COM input and less likely that it should always have the same effect. There is a pin that needs grounding if you are not using GPS.

Thanks Mark, I'll double check that, thanks also to everybody for the other suggestions, much appreciated. Paul DJ0CU [email protected]> wrote:

Hi Folks, I have a few Progrocks doing various duties here. One of them has a strange problem that I can't fathom and could use some ideas on the probable cause. This fault has started recently, the

Lloyd, No reply from August 20? As Reiner says "Where does the 8.99 come from. Check the voltages each side of R59. If something like 2.5V look for solder bridges around IC8. 73 Alan G4ZFQ

Just a suggestion, but you might want to try getting all three back to about the center of each of their ranges and go through the procedure again. Since the resistors are multi-turn without real

Paul, These set the image rejection. The receiver will seem to work particularly well as you may be receiving the images as well as the wanted signal. This is often caused by a missing signal from one

Hi Paul, You may want to check you got the enamel off the T1 winding as this was the culprit for me - the three variable resistors did little to nothing until I resoldered my T1, then they worked

Hi, I have a strange situation, after removing 5 turns from the large T1 Toriod to optimise the BPF output, I can now adjust the BPF to maximum without the Variable C being fully open. However when

Hello, I think the problem is between IC6 / 7 output and IC8 input. Also check the infeed Sidetone. The 8,99v have to come from somewhere That's my guess from afar. Reiner DL8LRZ

, I tried to calibrate the frequency using Menu 8.5. I am noticing that regardless of what I change this value to, the frequency on Menu 9.5 stays the same. Erik, I'm not sure what 9.5, the frequency

Hello all, I just finished building my first 40m QCX. The build was very fun and powered up great at first power. I setup WSPR and let it run for a few hours without any hits. I started to do some

Is there any one out there that will repair a non working QCX 40. I just built it and will not have time to trouble shoot it for the next 4 months. The display lights up, but no data is displayed. ?

I've soldered in hundreds of ICs and IC sockets and NEVER got one in backwards! However I HAVE ruined chips with solder bridges and trouble-shooting with a slip of the probe and shorted out two pins.

Arv, You’re correct on all accounts. What has bothered me on this QCX build (and for myself on other projects) is to be trouble shooting to find a problem and inadvertently stick a probe between two

Thanks for the reply Andy. I went ahead and gave it a try and it seems to be working fine just as you'd suggested it would. Just for fun I looked at the ripple on the converter's output with my

Thanks for the help!? I've decided to go with the TS922 in the SOIC package and also ordered a few SOIC to DIP adapter boards from oshpark ( https://oshpark.com/shared_projects/SmjbVWMC ).? In the