"Molesworth" wrote in message
...
Can a Raytheon Autohelm series ST7000+ control unit replace a faulty
control head from an ST4000 as a straight swap?

Molesworth

I believe Jeff is correct. The ST4000 and ST5000 control heads also contain
the course computer but the ST 6000 and 7000 series are just control heads.
I believe an ST5000 can drive an ST4000 wheel pilot .
Both used heads do turn up on eBay from time to time.