Kai, those sweeps show that you may not be getting any RF at all through your receive path.?
Before trying the PCM1804 tests, I would first examine these four things:
1) make double-sure you installed the LPF switching diodes in the correct direction (D508-D513).
2) carefully inspect the soldering at the BNC jack, and make sure there isn't a bridge between the center and ground pins - noting that there is an extra hole for the optional SMA center pin that is easy accidentally bridge to one of the corner ground pins of the BNC; note that you must inspect for such a short visually, because a continuity check with a meter will always show a DC short between the center pin and ground, due to the T507 transformer winding.? While you're at it, check that none of the terminals of T507 have solder blobs bridging them.
3) inspect L513 and L514, making sure both ends are soldered, and the inductors are not cracked - they are a bit fragile, and some users have accidentally cracked them during handling after soldering them in;? you can check for a crack doing a continuity check with a meter, it should show continuity across the inductor terminals.
4) check carefully the soldering of all of the leads of the trifilar transformer, but particularly the one closest to the edge of the card - re-heat it and hold the soldering iron on it for a few seconds.
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Any of those four things would not allow RF from the internal test generator to get through the receive path, and would affect all bands.? There are other possibilities, but these are the more common ones related to assembly.
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And if you have a signal generator and sensitive oscilloscope, and use them as outlined in the PCM1804 test, you may be able to trace the signal from the BNC through the receive path and see where it is missing, at one of the 4 above locations, or elsewhere.
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Stan KC7XE
