THE FIRST CAR TELEPHONES, INTRODUCTION
The first car telephones linked to the Public Switched Telephone Network in the United States had been put into service in 1946, as a response to the growing mobility of the American inhabitants within the postwar years. Initial design of the mobile phone itself was undertaken by the Western Electric Corporation, the prime provider of phone sets to the nation’s Bell System working firms, whereas Bell Laboratories itself designed the general system and set the specifications for the tools. At the same time, the unbiased phone companies were creating their own tools, to be supplied by Automatic Electric. The Bell System tools built upon an already existing mobile radio set, Western Electric’s 1945 vintage Type 38 or 39 VHF FM police radio gear, adding a phone fashion handset and a selective calling decoder, which rang a bell within the automobile when that phone’s unique quantity was signaled. The selective calling decoder consisted of a small wheel in a glass enclosure, with pins situated at certain points around its circumference. The decoder had been developed in the nineteenth century for railway right-of-way signaling, was later used in ship to shore radio phone installations within the 1930’s, and was a confirmed idea. This decoder was labeled “102.” Western Electric and the Bell corporations thus didn’t draw up a wholly new idea for a car phone in 1946; they used proven components of other systems to create the brand new public automobile phone service.
Mobile telephone gear had already been in use internally within the Bell System on an experimental basis, going again before WWII, using mobile radios such as the Western Electric Type 28 VHF tools. One instance was the Emergency Radiotelephone Service established by New York Telephone in December, 1940, which used AM on the Megacycle band. Based on the profitable checks of that equipment, AT&T announced the creation of the General Mobile Radiotelephone Service on June 29, 1945, and applied to the FCC for authority to establish base stations in Baltimore, Chicago, Cincinnati, Milwaukee, Philadelphia, Pittsburgh, St. Louis, Washington DC, Columbus Ohio, Denver, Houston, New York City, and Salt Lake City. One has to marvel why nothing was initially thought-about for California.
The FCC and the Bell companies envisioned two forms of mobile telephone service, “HIGHWAY” and “URBAN.” Both could be VHF, and each would use FM. The “Highway” service, as its name implies, was meant primarily to serve the most important land and water routes that existed throughout the United States within the 1940’s, which might not be served by the “Urban” methods. Highway service was meant for vans and barges on inland waterways quite than non-public autos. Highway service was allocated 12 channels within the VHF “low band,” with the mobile tools receiving on 35 Megacycle and transmitting on forty three Megacycle frequencies, although not all 12 channels have been initially used. The Urban gear, as its name implies, was intended to serve mobile subscribers whose travels took them primarily within the quick radius of a major urban heart, corresponding to medical doctors, supply vans, ambulances, newspaper reporters and so forth. Urban gear operated on VHF 152 Megacycles (receive) and 158 Megacycles (transmit,) and the initial FCC allocation in 1946 was for 6 channels. The separation in transmit and receive channels was essential to offer a “half duplex” communications circuit, and allowed the phone firm base station to remain on the air repeatedly through the duration of the call. The first Highway system went on the air in August 28, 1946 in Green Bay, Wisconsin, and the primary Urban system went on the air in Saint Louis on June 17, 1946.
By 1948, Urban service was obtainable in 60 cities in the United States and Canada, with 4000 mobile subscribers, dealing with 117,000 calls per thirty days. Highway service was in place in 85 cities with 1900 mobile subscribers, handling approximately 36,000 calls per thirty days, with most main highways within the east and Midwest covered.
The Bell System also entered the two-way business and police radio market after the war by providing the rental of entire radio techniques together with their maintenance and updating. This gear was marked “Bell System” either in white painted letters or with water-slide decals. Smaller police departments have been inspired to make use of the “Urban” mobile phone system as opposed to a conventional dispatch system, which will have to have been considerably odd in operation. Most of the equipment rented by the Bell System associates was Motorola two-piece “Deluxe” tools, FMTRU-5V “Dispatcher” and GE one-piece pre-Progress Line radios. It is believed that the Bell System discontinued this apply someday within the early to mid 1950’s.
Map of Mobile Telephone Land Stations in Service or Planned in early 1947:
Map of first “Highway” Mobile Telephone Land Station channel assignments, early 1947:
ORIGINAL URBAN SIX CHANNEL ALPHA-DESIGNATORS:
WJ WR JL JP JR JS
ORIGINAL HIGHWAY ALPHA CHANNEL DESIGNATORS:
ZF ZH ZM ZO ZB ZA ZL
POST-NARROW BANDING ALPHA CHANNEL DESIGNATORS:
Highway: ZO ZF ZH ZM ZA ZY ZR ZB ZW ZL
Urban: JL YL JP YP YJ YK JS YS YR JK JR
UHF: QJ QA QP QB QR QF QS QH QW QL QX QM
Typical installation of the primary automobile telephone:
WESTERN ELECTRIC 238 and 239 EQUIPMENT AND 41A CONTROL HEAD
The Western Electric house-made equipment consisted of two pieces; the transmitter cupboard and the receiver cupboard. These mounted within the automobile trunk, and a big cable introduced ahead underneath the carpet connected to a “management head” under the dash which contained a phone handset. The control head featured two illuminated lenses–one indicated that the tools was turned on, and the other would illuminate when the mobile phone was known as. The Western Electric Type 38 was Highway band tools, i.e. VHF low band, and the Type 39 equipment was Urban, or VHF excessive band gear. A full installation could be prefixed “2”; in different words, kind 238 could be an entire Highway mobile telephone, and sort 239 a whole Urban mobile telephone. As originally provided, all tools was single channel in operation though two channel enlargement was possible.
Transmitter proven under
The first Bell System mobile telephone control head was the Western Electric Type 41A, seen beneath. The handset, with a cloth braided wire, stores in a curious-looking spring loaded pocket on the bottom of the management head. The bell and terminal strips for cabling are self contained within the 41A. There have been two styles of 41A management head; the difference was solely in the faceplate across the pilot lamps and toggle change. The authentic 41A had two exposed lamp lenses as shown. The later model had a easy plastic sheet with colored lens sheet items set behind it. The 41A set was technically a single-channel set up though a multi-channel switch was developed which mounted alongside in a separate box.
Type 41A Control Head with non-original rubber coiled twine, a later replacement:
The gear for decoding a ringing sign to a particular automobile was a rotary stepper wheel with a latch, designed to rely inbound pulses as they have been dialed from the land aspect station, situated on a chassis called the “Selector.”. The land station’s signal consisted of alternating pulses of 600 and 1500 Hz tones representing the varied numbers. The description of how this labored is beneath. If all the best numbers were acquired, the wheel would attain the end of its journey and a bell can be activated both inside the control head (41 Series) or (later) in a bell field under the car dash (47 Series.)
In 1949 a typical quantity scheme for the gear was as follows:
Type 38B Urban 6 Volt
Type 38C Urban 12 Volt
Type 39A Highway 6 Volt
Type 39B Highway 12 Volt
WETU-30-D Urban Motorola Deluxe 6 Volt
WETU-30-12D Urban Motorola Deluxe 12 Volt
In the kind 38 and 39 receivers, the decoder circuitry was mounted contained in the receiver chassis. Western Electric also manufactured a separate housing for this decoder, such that it could presumably be used with different makes of mobile radio gear, such as the Motorola “Deluxe” line two method FM radios and the GE 1949 “Pre Progress Line” two piece sets. The separate Selector Set was known as the 106A. See under.
CLICK HERE FOR A PHOTO OF A LATE TYPE 41A HEAD IN USE
WESTERN ELECTRIC 106A SERIES SELECTOR SET:
The decoders in these sets had been capable of responding to a maximum of five digits, and operated by a series of small pins placed in holes across the circumference of a toothed ratchet wheel. As the operator dialed a specific mobile unit, all of the wheels in the entire cell phones within range would start to maneuver in step with the pulses being dialed from the telephone company’s base station. At the end of the primary digit, solely these mobiles with pins within the wheels set to that quantity would hold the wheels at that spot. The others would reset to the remaining position. This course of would continue via the fifth digit, at which level (ideally) all of the decoder wheels in the different cell phones would have returned to the remainder position except the one whose five pins matched the number dialed by the operator, at which point the wheel would shut a switch and the mobile’s bell would ring. The signals from the telephone firm have been audio tones, alternating between 600 and 1500 cycles as a digit was dialed. It was attainable to hear the stepper wheel working in your trunk with calls for different individuals, and even to anticipate when your cellphone would ring by listening to the stepper ratcheting.
This first system of mobile telephony would come to be referred to as “MTS.” There had been no dial services in the cars – – to initiate a name, the push-to-talk button can be depressed briefly, which might trigger a lamp to gentle at the mobile operator’s switchboard and put the bottom station on the phone firm on the air. The mobile unit would give the operator its phone number and city of registry, and the specified quantity to be dialed. The mobiles were not “duplex,” i.e. operation of the handset pushbutton was “push to speak,” and “launch to listen.” The majority of the mobile telephones had no squelch circuit, so the attribute FM “speeding” noise would emanate from the handset every time the bottom station went off the air. This was not an issue because the handset audio was muted every time it was hung up on its cradle.
Equipment manufactured by Motorola (the “Deluxe Line”) was also placed in service together with the Western Electric, principally on the “Highway” channels, along with a small variety of GE two-piece FM transmitter-receivers (also for “Highway” service.)
Independent telephone firms utilized equipment practically equivalent to that of the primary Western Electric car telephones, which was manufactured by Automatic Electric Co. as shown under, and believed to have been used with Motorola and GE radios:
MOTOROLA “DELUXE” LINE ADAPTED FOR MTS USE:
The photo beneath exhibits a Bell System Motorola “Deluxe” line high band ( 150 MHz) “Urban” radiotelephone installed in a taxicab in Delaware in 1948, taking on practically the complete trunk. Many of those items had a sheet steel plate tack welded to the higher cupboard lid overlaying the connector space. This was to maintain the connectors and cables from being bashed to items by issues being thrown into the trunk, and were usually seen in taxicabs.
The Type 106A rotary signaling selector unit is proven on the far right. The receiver would have been a model FMRU-16V modified for Western Electric use and (apparently) renumbered WERU-16-V (for a 6 Volt receiver.) The transmitter would have been the WETU-30-D ( 6 Volt Urban dynamotor powered transmitter) which in Motorola numbering was the FMTU-30D.
The cabinets on these models present that they’ve been “recycled” by the Bell System already — one is slightly older than the other and so they don’t strictly match. These had been regular two method radios modified for Bell System use by incorporating the exterior selector unit and a telephone-like management head.
In the image under, the far left is the receiver, the middle the transmitter, and the far proper the 106A Selector Set.
Notice that this guy should be shopping for a model new spare tire!
Land Station Side
Below is a photograph of the typical distant receiver used to feed the sign from the cell phones to the central office operator board, on this case known as the G2 Console. They had been mounted in a weatherproof cabinet at the backside of a telephone pole, with the antenna on the prime of the pole fed with fuel crammed concentric cable. There had been usually a number of of these receivers situated at strategic points, however just one transmitter. This one was outside Philadelphia and uses a Motorola FSRU-16B receiver on 157 MHz..
REMOTE RECEIVER USING WESTERN ELECTRIC TYPE 38 EQUIPMENT:
The view below shows a distant receiver web site the place the receiver itself was inside a railroad right-of-way constructing which seems to have as quickly as been a small station, already boarded up by 1947, someplace close to Philadelphia.
Shown under are typical views of a central office switchboard and tools. In this case, Philadelphia, 1946, the Western Electric G2 management console. The racks represent the console within the switch area of the telephone plant and the wooden switchboard and toll-ticket printer are inside on the main operator area. Note the Western Electric “Urban” and “Highway” VHF receivers mounted along the tops of the rack frames. The transmitter was situated elsewhere.
The caption for the photo below reads:
“Western Electric G2 Control Terminal. Terminal services for mobile telephone service within the Philadelphia area include 4 Western Electric G2 Control Terminals. The cabinet sort on the left is for the Philadelphia hyperlink within the New York — Washington Highway System. The first rack mounted type on the left is for the Philadelphia Urban channel # 1 (FCC # eleven.) The three sq. bins over the fuse panels are filters within the incoming AC power traces to cut back noise. The receiver at the prime is for monitoring. Each of the receivers at the high of the racks are for monitoring their respective channels. The center rack Type G2 is for the Philadelphia Urban channel # 2 (FCC #9.) The right hand rack Type G2 is for the Urban channel # three (FCC # 7.) Railroad service for the New York to Washington run is also additionally handled on this channel. The apparatus just over the G2 tools on the best hand rack is an A1 noise reducer J6806L1 and an appliqué unit used in reference to the railroad service.
Photo under of mobile operator in Michigan Bell central workplace.Back of picture reads: “MOBILE SWITCHBOARD – – Calls to and from mobile items are dealt with by a particular ‘mobile service operator’ in the Michigan Bell Telephone Company’s main office. Miss Pat A. Voige is shown as she completes the primary calls over the model new system here. “(1948)
Photo beneath reads on back: “Leslie F. Hamelin, toll technician, keeps an in depth watch on strength and quality of signal at management middle in central office building. (Michigan Bell, March 1948)
MOBILE PHONES ON TRAINS
CLICK HERE for the page showing a 1947 mobile phone system installed as a public cellphone booth on a Pennsylvania Railroad train.
BELL SYSTEM SHORT FILM
CLICK HERE for a short movie from approximately 1948 showing the first Bell System telephone techniques in use.
EARLY CAR TELEPHONES ON TV
There are assorted films and TV shows which made use of the earliest mobile telephones. I hope to list them right here as they become recognized. In many instances solely the handset is shown and it might be assumed that there was no actual control head and solely the “prop” handset was used. But some show the complete management head. Some motion pictures, whereas trying to characteristic automotive telephones, show only full props or different fakes. An instance can be Sabrina,starring Humphrey Bogart, which sadly reveals only a pretend mobile telephone control head and a ridiculous gigantic antenna on the limousine it’s mounted in. Genuine early MTS automobile phone sightings are listed beneath:
1) The Feb. 15, 1960 ( Ep. 21 Season 2) episode of Peter Gunn, TV detective present, entitled “The Hunt,” options the Type 41A control head in Gunn’s car, at approximate time hack 10:08 . Great view of the management head.
Unfortunately these episodes are endlessly being eliminated by YouTube following copyright infringement claims and there’s no method to make a hyperlink work here for longer than a couple of days!
2) A few other Peter Gunn episodes circa show him utilizing the same MTS mobile phone as nicely, such because the January 4, 1960 episode (Ep. 15 Season 2) entitled “Hot Money” (you can skip forward to approximately 20:40 if desired.)
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