Tim -

Going from memory it looks right. I'll try to dig up the docs tomorrow and check. I do remember that Northern Electric/Telecom Logic 10 & 20 sets were different then WE/ITT/AE/Stromberg sets after the first 6 lines. (So watch out for those)

Jeff -

When you say "skip pairs" are you referring to the "A" leads jumping around and/or the Y/O, Y/Sl pairs?

On a six button set the first five lines went in order. Yellow/orange was the Intercom Buzzer, Yellow/ Green was the Hold Lamp and Yellow/ Slate was the Ringer. When they went to 10 button sets on 25 pair they tried to keep those signalling pairs standard.

Sam

"Where are we going and why are we in this hand basket?"