Mark,
The TV-502S pin outs is:
pin 1 ALC out
pin 2 N.C.
pin 3 screen voltage through
pin 4 N.C.
pin 5 -100v from rig
pin 6 10 meter output to rec.
pin 7 rec ant input for pin 6
pin 8 relay key to ground
pin 9 ground
pin 10 same as pin 3
pin 11 ground
Hope this helps. 73, Mark WB8JKR