Discussion relating to the PRR, up to 1968. Visit the PRR Technical & Historical Society for more information.
  by Allen Hazen
When did the PRR discontinue use of its system of inductive train phones? And how fast was the equipment (in particular, the visible "handrail" antennae along the roof) removed from rolling stock equipped with it? Glancing at PRR locomotive photos on George Ellwood's "Fallen Flags" rail image site (invaluable resource!) I saw a couple of locomotive photos dated 1965 and 1966 that showed the antennae, but the 1967 and later photos that I checked didn't have them. (But I only checked a few.)
  by ExCon90
The PRR indicated in its employee timetables which towers had radio. Among what I have I found the following:

Western Region TT No. 5, effective Oct. 30, 1966, and
Central Region TT No. 4, effective Oct. 29, 1967.

In the reference marks for the List of Stations at the beginning of the timetable, the Western Region TT from 1966 shows a capital O for trainphone, a solid 5-pointed star for radio, and a star in a circle for radio and trainphone; the Central Region TT from 1967 shows only the star for radio. CUSTER tower, on the Panhandle west of Mingo Junction, appears in both timetables, with radio and trainphone in 1966, but only radio in 1967. CRESTLINE also appears in both timetables, but with only radio in both years. Apparently there was some overlap as radio was phased in, but trainphone appears to have been discontinued by fall 1967.
  by Allen Hazen
Thank you for that information! The locomotive photos I had looked at were of high-horsepower (for the time!) units which probably could show up almost anywhere on the system (at least on main lines): Alco Dl-640 and GE U25B. Since some had had their trainphone "handrails" removed in 1967, (i) this must have been about the end of train phone and (ii) removal of the equipment was done pretty quickly after the phase-out.

There are costs to being on the "bleeding edge" of technological change. PRR management was very progressive in adopting trainphone: the near universal adoption of radio by railroads after WW II shows the value of improved communication with train crews. But they guessed wrong about the technology that would win out, and so later had the expense of scrapping and replacing a working system!
  by JimBoylan
Did other roads use Train Phone?
I've seen photos of what seem to be Train Phone pipes on streamlined observation cars, both PRR and other roads. Were they for the conductors' use, or to provide commercial AM radio shows to 1st Class passengers, as heard in the movie "Broadway Limited"?