I have no way of proving this...

I think sony's RF 15 unique code variation strategy is flawed. I was getting ghost commands on my Sony DSS set for RF code 001. I assume these were coming from a neighbor's remote so I changed the command set to 010. Within a day I had more ghost commands, so I changed the code again... and again, and again. Thinking MY RF remote might actually be changing THEIR receiver's code setting, I used my Pronto with the receiver set to IR to get into that menu before changing it. It didn't matter. I was getting ghost commands on every RF code channel I picked. A quick look around the neighborhood revealed only TWO DSS dishes, so I've come to this conclusion:

There is no significant distinction between RF code set 001 and any other code set in Sony Receivers. I'm using a SAT-A4.

I'm now using IR mode entirely.

Dave