I’ve never had noise from an on-board source, but that doesn’t mean it couldn’t happen.? There is probably a solder bridge somewhere that is causing this… but keep it simple… to hone in on the area of the circuitry with the issue.? Oliver had some good input… if the clocks both look good… you can follow a calibrated input into the receiver front end… past the transformer (TP4), then past the attenuator and the gain stage (TP6)… if all that works there is only the mixer U1 and the filters at TP5 and TP3.

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Here is another great diagnostic tool that a lot of people forget about.?? You can take the RX I/Q output at J1 into your computer through the stereo input… load a SDR program like SDR Console and demodulate the signals as if it were the Main board.? [Note: this also means that with the addition of a simple software subroutine/ control module to the suite of existing provided modules in any of the SDR PC programs, anyone could build only the RF board and have a fully functional QRP Transceiver.? Other boards could be added to additional functionality].

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Dr. William J. Schmidt - K9HZ J68HZ 8P6HK ZF2HZ PJ4/K9HZ VP5/K9HZ PJ2/K9HZ VP2EHZ

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Owner - Operator

Big Signal Ranch – K9ZC

Staunton, Illinois

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Owner – Operator

Villa Grand Piton – J68HZ

Soufriere, St. Lucia W.I.

Rent it:

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Moderator: North American QRO Group at Groups.IO.

Moderator: Amateur Radio Builders Group at Groups.IO.

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email:? bill@...

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