Early Police Band Radio

I got to thinking about the police squad post on Friday and realized I skipped some back history I should have covered in advance. They were the replacement for Police boxes an innovation of 1877. Call boxes were in regular use into the 1950s. Police radios solved the basic problem there which was that one location is centralizing information and the multiple users that most need that information are in transit. (see how I used modern nerd-speak to express that.. it's called irony) It's the sort of problem we now solve with cell towers, wi-fi and a number of other toys. back then we had to get very clever.

Police band radios came in many different configurations. Some operated on multiple channels but one channel at a time. As early as 1907, two-way telegraphy was commercially available but not on a scale that would make police use tractable. Early two-way schemes operated on a simples configuration. Only one station could transmit at a time since all operated on the same radio frequency. The (FRC) Federal Communications Commission assigned only eight radio frequencies for all police departments in America. This was a serious limitation.

This was solved with duplexing. Receivers and transmitters were simply set to different frequencies. Suddenly simultaneous transmission and reception were possible. I've read some early adopters had to use morse code but I've not found anything that collaborates that.

EARLY ADOPTERS

In 1921, Detroit Police Commissioner William P. Rutledge had a radio transmitter installed at police headquarters and in 1922 the FRC, issued a provisional commercial radio license for, 1050 KOP-AM. They had some difficulty maintaining the license as they did not operate continuously. Frequency changed to 1080 in 1925 and was deleted thereafter. More here.

833 WLAW-AM was operated by the NYC police department starting in 1922. It was deleted in 1924. It sent out alerts to police officers. It's primary use was by special radio-equipped motorcycle patrols. The station was managed by M.R. Brennan, superintendent of the NYPD's Telegraph Bureau. More here.

You'll see that most of these share the same frequency. This continued until 1938, when Sheriff Biscailuz debuted a genuine two-way system on 31.90 mc with a callsign of KQBV. More here.

1929 Indianapolis WMDZ 1714 Khz

1930 Berkeley KSW 2410 Khz

1930 Tulare WPDA 1712 Khz

1930 Pasadena KGJX 1712 Khz

1931 Los Angles KGPL 1712 Khz

1931 Omaha KGPI 1714 Khz

1935 San Bernadino KGZY 1712 Khz

???? St. Louis KGPC 1712 Khz

???? Chicago (WPDB, WPDC & WPDD) 1714 Khz

1933 The Bayonne, New Jersey police department successfully operated a two-way system between a central fixed station and radio transceivers installed in police cars; this allowed rapidly directing police response in emergencies. The very high frequency system developed by radio engineer Frank A. Gunther and station operator Vincent J. Doyle. The system operated in “push-to-talk” set up. In 1949 the FCC decreed that all police radio systems were to be limited to that VHF bands.. putting an end to the 4-letter calls.

Radio on the Twilight Zone

The Twilight Zone "Static" Season 2, Episode 20.The original air date of this episode was March 10th, 1961. In this script, an old man, Ed Lindsay, obtains an old radio, which he listens to and hears old shows and music from his younger days. But other people only hear static. The radio reunites him with his lost love but 20 years into his own past, where he can relive his life and set things right.

In the episode he clearly refers to the calls and city for the radio station. These are: WPDA-AM Cedarburg, New Jersey. Currently there is a 106.1 WPDA (simulcast WPDH) in Jeffersonville, NY to the west of Poughkeepsie. In 1930 the Pasadena, CA police department used those calls on 1712 kHz. However, a 1936 issue of Radiotron puts the calls in Tulare, CA; some 170 miles north. A 1934 issue of Shortwave Craft puts the same callsign in Framingham, MA on 1666 kc concurrently with the other Tulare listings. Something is amiss there.

There is no Cedarburg in New Jersey, but there is one in Wisconsin outside Milwaukee. There is a Cedarville, a Cedar Grove and a Cedarbrook but none of these has a local stick. This still may of course be a veiled reference to some radio station from the resume of writers Oceo Ritch or Charles Beaumont. 

It originally aired in March of 1961 starring Dean Jagger as the cranky old man. The context here is that may old radio writers were re-purposing themselves as TV writers about then. It's a script an old radio man, who didn't feel that magic in TV, would write. More info here, and here.

It wasn't until 2002 that The Twilight Zone TV show was adapted as a radio drama series of the same name. Of course this is the opposite of the traditional media shift.