Given an SX-100. It doesn't work.

Chassis and interior in good shape, no corrosion. Lights fire up when
turned on. Attached Hallicrafters 3.2 ohm speaker (or headphones if
plugged in) hums, and I hear scratchy noises when I change across the
bands or switch to phono. S-meter moves across the dial when I spin the
sensitivity knob.

But, it doesn't actually receive anything, and the S-meter does not
move as I traverse the bands nor does it change as I move within a
band.

Suggestions on priorities for troubleshooting, by tube replacement or
otherwise, appreciated. I feel the detector is the place to start?
Have a multimeter, is all. In Portland (OR) Metro area.

0A2 voltage rectifier $6
5Y3GT rectifier $10
6AU6 1st mixer & crystal cal (1 ea) $10
6BA6 1650 KHz IF amp, 2nd mixer, 50.5KHz IF amp (1 ea) $8
6BJ7 detector/AVC/noise limiter $5
6C4 1st conversion oscillator & KHz IF amp (1 ea) $13
6CB6 RF amp $5
6K6GT audio output $8
6SC7 audio amp/BFO $9
12AT7 2nd conversion oscillator $13

Your Elmering would be appreciated. Thank you in advance.