Does the RX have a "cue" button like the RX 2? If yes, put an LP on the table. Press "cue." The platter should spin and the tonearm should move to inside the outer edge of the LP, but the tonearm should not lower.
Where does the stylus line up on the record? "Somewhere over the approximate middle of the lead-in groove" is the proper answer.
On an RX 2, if you're too far toward the outside, the stylus can slide off the edge of the record rather than fall into the lead-in groove and ultimately begin playing the record, even if the anti-skating is fine.
If you're too far toward the outside, you can adjust where the tonearm moves to when "start" or "cue" is pressed. Or you can simply press "cue," wait for the tonearm to move into position, nudge the tonearm to the left a bit with your finger, then press "cue" again to lower the stylus onto the record.
One other thing the first: are you sure your stylus still has a decent tip?
One other thing the second: where are you located where you can get a working RX for $50 on Craig's List?
Current primary listening: SMMC20EN -> BG4002 -> BM4000 -> Beovox M70