Railroad Radios
Curious as to what radios the railroad uses in the cab's? ANyone know?
I believe they use a unit called "Spectra" which, if I'm not mistaken, is a Motorola product. As far as I know, all of the Class I's and most of the Class II's use this particular type of radio, although they may use different models. It is capable of transmitting and receiving on two different channels simultaneously in a duplex mode. All of the Class I's transmit and receive on the same channel in simplex (example 3737, or 160.665 MHz on both channels). Florida East Coast Railway (Class II regional; FEC) is one of only two railroads I am aware of that uses an actual duplex operation (example 2844, or 160.530 MHz for the dispatcher, and 160.770 MHz for the train crew). Amtrak (AMTK) often uses two different frequencies at once; one is used for talking to the dispatcher, while the other may be used for inter-train communications. There is one Class III short-line railroad I am aware of that uses the split duplex mode, and that is Akadiana Railway (AKDN) in southern Louisiana.
The Spectra is capable of operating on 99 channels, which includes the 96 railroad channels (90 channels in the US from 07 to 97, and in Canada from 02 to 97). The radio includes a keypad to allow the conductor and/or engineer to alert the dispatcher using tone squelch, to operate radio-controlled switches and gates, and to access a mobile phone patch, for those railroads that use them.
The radio can also be programmed for operation on UHF channels if a repeater is used. I know of one such instance where Southern Pacific in Colorado used a UHF repeater between Denver and Glenwood Springs, given the mountainous terrain. Train crews were instructed to use the repeater frequency when on that portion of the railroad. The railroad placed repeaters in strategic spots so that train crews would never be out of touch with the dispatcher or maintenance crews.
The radios can transmit with a maximum power of 110 watts and can be powered from either 12 VDC or 72 VDC (depending on whether they are used in a ground vehicle or locomotive, respectively).
I hope this answers your question.
73 de NØJAA
PS: I have heard of Amateur Radio Operators obtaining some older Spectra units and reprogramming them for use on 2 meters. As the two radio services are not far apart in frequency (approximately 12-14 MHz), only slight tuning would be required to get a good SWR with one of these radios.
