Bob, 

the answer to your question regarding AP and UPI depended on when.

The radio station in my small hometown in Georgia was an AP subscriber, 

and the telco loop was a DC circuit from the central office in town.  That was 1960.   

At some point in the mid to late 1960s, maybe even later, the AP wire was converted from

a DC circuit from the telco to a tone pack feed circuit.   The AP used a Lenkurt 25 tone 

system, up to 25 AFSK circuits on one voice grade channel.  The Lenkurt unit at the AP

bureau was a rack mounted unit with the individual tone cards.  The Lenkurt unit at

the subscriber was a small box, about the size of a shoe box, with one tone demodulator

card and a power supply for the loop current.

I believe UPI ran the same system.

Hopefully long past the statute of limitations - in the mid 1970s, I was working for some

radio stations in North Carolina.  Election season and management wanted to do live 

reporting from the county elections office and they also wanted the UPI wire at that location.

I had contacted UPI for the cost of a short term circuit to the county elections office and

the price was, well, not within the budget.   I realized that the UPI circuit was a voice grade

circuit from "somewhere" and I just had to local telco establish a copper loop from the 

radio station to the elections office.   I jumpered the UPI tone pack audio over to the 

loop, picked up the UPI Extel printer and a roll of paper, took it over to the elections 

office and it worked fine.

73

Sheldon

WA4MZZ