PRR Inductive Telephone (old time radio) query

Fellow members,

It's been with interest that I've viewed the huge antenna arrays put on top of PRR locomotives and hacks for radio service in the "old" days. How did these "inductive telephones" work in contrast to our "modern" UHF and VHF radio systems?

THX all,

de Don, n2qhvRMLI

Think of them as your cordless telephone in the house rather than as your cell phone and you'll have an idea of how they worked. The "circuit" was from the receiving coil and the transmitting antenna to the telephone wires alongside the track, a maximum distance of 50 feet or so.

thirdrail,

Thanks for the info.

The transmissions must have had some serious power output to get into the telegraph wires and produce a useable signal equal to the length of a train, fore and aft. Do you know anything about the transmission equipment used by the PRR, it's history or manufacture? Does anyone know of any technical manuals, books or the like surrounding this historic equipment?

Thanks,
de Don, n2qhvRMLI

I worked for the PRR in the Traffic Department, not operations, but I understand that the cabin car and locomotive did not communicate directly through trainphone but through the switchboard, like a call between two offices. It was actuallly used more to communicate with tower operators, station agents, and dispatchers than between crew members, AFAIK.

Here's an example of PRR train phone antennae:

http://www.subwayspot.com/gallery/album60/04_08_01_037

http://www.subwayspot.com/gallery/album60/04_08_02_001

Don,
If your extra kind to me and snag me a picture of 39's power reverse unit I will send you a scan of a K4 with the antennae.