DX-99v2 - 690011D board - Same as DX-959 — No AM receive

Is the AM/FM rec totally dead absolutely no sign of even a very weak signal? And is it on freq. and modulating the way it should across all modes?

AM/FM rx patch starts on FL2 through Q8 to FL1.
If you touch FL1 legs can you hear broadcast AM stations come through speaker?
Check D4, 5, 6.
Mike

That's where I start, with the "Manual Digital Signal Injector".

Lay one finger (digit) alongside the shaft of a small screwdriver, and touch the input, then the output pins of FL1.

Should hear a lot of noise on the output pin, typically including any nearby AM-broadcast stations.

Input pin should still yield some noise, but not as much.

Checking voltages on TR8 would be next if it passes the MDSI test.

And if you get no noise this way, a shorted C19 is common in old radios. Pretty rare in a new one, though.

73

When you did the Clarifier mod, did you use R113 feeder?

Else AM and FM uses J14 to "feed" the X4 Oscillator for SSB Conversion as well as AM and FM - so best to check and locate D53 - for 8 volts - part of that Oscillator that sends RF at TP6 . As well as Double-Double check J14 work.

IF you don't have any power for X4, you won't get any IF either.

So locate X4 and TP6 - is FM and AM show up as signal on TP6 - well, you have a heartbeat, but D36 may have got "zapped" it's used as a PIN diode switch at TP6.

(Now some of you may think it's a little offbeat, yes, considering the TX side works, But R113 feeds clarifier on RX, so if RX is not right or J14 header is off, or D36 is zapped or just plain not soldered in correctly - a carrier shows up instead of a deconversion signal as you would with SSB - silencing the RX in FM and AM modes - but you would not hear it or see it in AGC or S/RF meter actions - it's downstream from it...)

Good luck - Hope it's something simple - Cold Soldering does come to mind...

Yeah, what we call "Galaxy Syndrome".

Good to hear you nailed it.

73