Re: Unable to receive anything on my 20m #chat


gabri22_@...
 

Hi all, I've tried to listen on 14.074 MHz and I was unable to hear anything. So as a first approach to solve a possible hardware issue, I checked the voltages on the critical points pointed out in the manual. All of them seem to be correct except for the ones I attach:

I used 12.98V as the input voltage:
- IC6: Pins 1 to 8 should read: 2.44, 2.44, 1.63, 0, 1.55, 2.44, 2.44, 11.67 and I get: 2.88, 2.88, 2.87, 0, 2.87, 2.88, 2.88, 12.51. Should I assume pins 3 and 5 are wrong??
- IC7: Pins 1 to 8 should read: 2.64, 2.64, 1.99, 0, 1.89, 2.64, 2.64, 1.67 and I get: 2.91, 2.91, 2.90, 0, 2.90, 2.90, 2.91, 12.47. Again pins 3 and 5 are wrong?
- IC8: Pins 1 to 8 should read: 2.46, 2.46, 0.65, 0, 0.67, 2.48, 2.48, 11.67 and I get: 2.86, 2.86, 2.82, 0, 2.86, 2.88, 2.88, 12.50. Same situation?
- IC9: Pins 1 to 8 should read: 4.84, 4.84, 0.65, 0, 0.67, 2.44, 2.44, 11.67 and I get: 4.87, 4.87, 4.40, 0, 2.82, 2.82, 2.85, 12.50. Same weird thing for pins 3 and 5...
-IC10: Pins 1 to 8 should read: 5.83, 5.83, 5.83, 0, 4.21, 3.94, 5.83, 11.67 and I get: 6.26, 6.26, 6.26, 0, 6.20, 6.21, 6.22, 12.50. In this case pins 5 and 6 do not meet at the appropriate values.

Finally, some of the LCD voltages are strange too, but the LCD is working properly so I do not know whether this is related. Namely, LCD pin 4 is 0V when it should be 4.92, 7 to 10 are 4.96V when they should be ~1V and Pin 14 is 4.6V but it should be 0V. However, it is working fine...

I am sorry to ask so many times, but I am really lost with this.  I really appreciate any help or tip for continuing the troubleshooting.
Also, I've uploaded a new video where you can see that only "Phase Lo" alignment parameter seems to oscillate too much, just in case this is of any help.
https://www.youtube.com/watch?v=8IYG2aQI3CI
Thank you very much :)



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