L.A.P.D. Communications Division History, page 2

Two-way radios

In 1936, the FCC issued an "Experimental Service" radio license to LAPD - W6XPA - for testing of 100-watt mobile transmitters in four police cars, to study the properties and usefulness of 2-way radio. These radios operated on 30.10, 33.10, 37.10, and 40.10 megacycles in what was then considered the ultra-high frequency band.

It proved extremely successful, and the police department sought funding to equip all patrol cars with two-way radios. According to Frederic Crowder, W6ELC (and PG1115307), long-time head of LAPD's Radio Technical Division, there was a fair amount of skepticism about two-way, and a "widespread belief that this was an interesting novelty, but of no practical use." Limited funding, for just 200 cars, was finally aproved by the City Council in 1938. Since the budget did not allow for purchasing new radios, Radio Technical Division personnel built 210 transmitter sets in their shop, which was located in the basement of Lincoln Heights Jail. These "home brew" radios ended up operating for more than a decade. The cars still listened on 1712 kcs, but the FCC assigned five new mobile talk-in frequencies: 35.10, 35.22, 37.22, 37.78 and 39.38 mcs.

Despite antenna improvements at Elysian Park, radio coverage was not keeping pace with the city's growth. In 1941 the police radio shop built two additional transmitters, and they were installed at San Pedro and West L.A. Initially they transmitted on 37.50 mcs., AM. Mobile-frequency receivers were installed at these locations as well. The Valley continued to be served from Elysian Park.

Unfortunately the 37.50 frequency was unsatisfactory from the very beginning. It was plagued by high background noise levels, probably exacerbated by the fact that the areas covered by this frequency were becoming home to a number of new heavy industries - aircraft plants on the west side, and numerous civilian and Navy shipyard facilities in the harbor area. But the situation was soon to be resolved.

War broke out in December, 1941, and it was decided that for greater flexibillity and redundancy in the event of attack, all radio cars should be on one Control frequency. So in early 1942, the transmitting setup was changed. The control (talk-out) frequency was changed to 1730 kcs for the entire city. Elysian Park got a new 500-watt RCA Model 10M transmitter, the two 37.50 stations were changed to 1730, and a third remote transmitter was installed at Van Nuys. The latter three sites all operated at 175 watts. At the same time, just before wartime material restrictions took effect, sixty additional patrol cars received new two-way radios.

Industrial growth, and ever more-distant patrol beats were by now playing havoc with reception of the mobile units' transmissions at Elysian Park, so a better receiving site was needed. While Mt. Hollywood in Griffith Park was cited as the ideal location, wartime material shortages made construction impossible, so a compromise was found by mounting antennas on the roof of the Griffith Park Planetarium. The receivers were linked by dedicated telephone lines to the Monitor operator at Elysian Park, and from there to the City Hall "mic room." A two-way radio link was installed as a back-up to the phone lines, for both transmitters and receivers, using 33.46 mc and 39.50 mc, KFZA and KFZB. There were also back-up receivers for all mobile frequencies atop City Hall.

For the duration of the war, LAPD was unable to obtain any new or replacement equipment, but they were able to plan for post-war improvements. In 1946, the FCC's granted LAPD experimental license W6XKK for testing mobile radios on the 70 mc and 150 mc radio bands. Click here to see a report on one of the more interesting test sessions.

The 150 mc VHF band proved to have superior propagation and audio characteristics for mobile operation, and by 1947 the City of Los Angeles was granted a license for their first high-band mobile frequency, 155.01 mc. This was the first LAPD frequency to use FM modulation, as all the existing voice radio frequencies used AM. Another VHF-FM frequency, 154.77 mc, went into service later in 1947.

In 2004 LAPD is still using those two frequencies. 155.01 was for many years mobile "Frequency 7" for West Los Angeles Division. With the advent of the "ROVER" UHF radio system in 1982, it became one of the MDT (mobile data terminal) frequencies; now that the MDTs are on the 800-mHz band, 155.01 is again assigned as a voice frequency, though it does not appear to be in regular use at the moment. 154.77, "Frequency 6," was Harbor Division's mobile frequency until about 1967. At that time Chief of Police Tom Reddin authorized the use of car-to-car "tactical frequencies" for patrol officers, something Chief Parker had steadfastly refused to do, even after the disorganized response to the disastrous 1965 Watts Riots. As Reddin explained it to me years later, "Parker was scared to death he'd lose control of his officers if he let them talk to each other rather than going through Communications for everything." So 154.77 became known as "Tac 2," and it is still in use by some specialized units today.

Questions, corrections, comments? Please beam me an email, hmarnell@gmail.com

In 1948, the "talk-in" frequencies moved up to the 154-155 mc band (there were 7, plus the supersecret "frequency 9" for surveillance). Frequency 9 continues in use today as "Tac 1."

~~As the city grew in the 1950's, and radio traffic increased, a second dispatch frequency of 2366 kc was added for dispatching to the Valley, Harbor and West LA and Venice.~~

The Gamewell

The "Gamewell" call-box system has been in use in Los Angeles for more than a century. Beginning in the 1890s, the boxes were utilized for hourly call-ins by officers in the field, who all had fixed posts or walked footbeats. Callboxes were located in all patrol divisions, usually installed at intersections where two or more beats met. When practical, boxes were located along Division boundaries for efficiency and economy.

Early on, the policeman would open the box and pull a handle to identify himself to the city operator downtown. If there were no calls for him, he would receive a "two-bell" signal and be on his way. Three bells, however, meant there was a call for him; he would pick up the receiver and listen to a message telling him only to "See the man (or woman)," and the location - nothing more.

Such cryptic information was certainly not conducive to officer safety! A young policeman from the early 1910-era later wrote that this practice added to his misgivings about his new career. "It seemed to me the operator should have learned more, and the policeman answering the call should at least have some idea of what to expect. I had yet to learn that most police calls were brief and lacked detail. The important matter on any call was the address.¹" ( Nearly a hundred years later plenty of patrol officers have muttered the same complaint, though the operators and the equipment in use today are immeasurably better, and the information available by radio or MDT is tremendously improved ).

By about 1925, the system had been redesigned. There were over 500 callboxes throughout the city, each equipped with a Western Electric telephone handset, and they were now connected to the local Division station rather than to City Hall. At his appointed time each hour, the officer would pull a handle to identify his callbox to the Divisonal operator, and then give his name. If there were any calls or messages pending for him, they would be given, otherwise he would simply be "marked off" as having called in for the hour, and would receive the two-bell "you are clear" signal.

In the 1970s, the remaining private-circuit "Gamewell" system was integrated into the city's "Centrex" telephone system; the antiquated street-corner phone-sets were replaced with push-button phones, and the two plug-and-cord Gamewell consoles in Communications Division were removed.

LAPD CALLBOXES OVER THE YEARS

Though universally called "Gamewell" boxes, after the manufacturer of the vast majority of police and fire alarm boxes in North America, a number of L.A.'s callboxes were made by other manufacturers, such as "Cannon Electrical Development Co" (upper left photo) and Western Electric

1- "Defender of the Angels; A Black Policeman in Old Los Angeles by Lt. Jess Kimbrough, LAPD retired - available thru Amazon

NEW! 1954 "Daily Training Bulletin" I've been fortunate enough to obtain a copy of the 1954 "Daily Training Bulletin" of the LAPD. In a little over half a century, many things have changed so very much...while others, not a bit. Take a look at the section on Radio Communications in the 1950's... it's quite a hoot!
*Hot Sheets*
Before instantaneous availability of vehicle information by computer, Communications Division Teletype Section would send out, several times a day, "Hot Sheets" of recently stolen and wanted vehicles to all patrol divisions. Note the columns, sorted by the last three digits of the license numbers, from the "Zeroes" through the "Nines."

As vehicles were recovered, and new stolens reported, the Link Operator would periodically broadcast updates to the current hot sheet, and officers would update their copies. *You ought to listen soon. These broadcasts have already been gone for 30 years:* 363 kb WAV file -or- 136 kb mp3 file