Think C was the Data common. SP was the speaker output
Honest, didnt look it up
Hmmm! Terminals 2 & 3 are Tx's, Terminal 5 is RX and Terminals 13 & 14 are Spkr. I've got the Installation Manual for the 1700 but it doesn't tell me what "SP" and "C" are.
Thanks anyway. Today is power up day on the Texecom, so it's fingers crossed!