Every time they 'patch through' a call to Hodiak, I do wonder if they had the technology to do that. It seems they not only 'patch calls' from the police station, but from the outside. Was that technology available and so common in the late 60's?
shareI used google and I think that they used switchboards back in the 60's. This is what they said on google
A telephone switchboard is a telecommunications system used in the public switched telephone network or in enterprises to interconnect circuits of telephones to establish telephone calls between the subscribers or users, or between other exchanges. The switchboard was an essential component of a manual telephone exchange, and was operated by switchboard operators who used electrical cords or switches to establish the connections.
The electromechanical automatic telephone exchange, invented by Almon Strowger in 1888, gradually replaced manual switchboards in central telephone exchanges around the world. In 1919, the Bell System in the United States also adopted automatic switching as its future technology, after years of reliance on manual systems. Nevertheless, many manual branch exchanges remained operational into the second half of the 20th century in many enterprises. Later electronic devices and computer technology gave the operator access to an abundance of features. A private branch exchange (PBX) in a business usually has an attendant console for the operator, or an auto-attendant, which bypasses the operator entirely.
That's regular telephone service. Police cars used 2-way radios which were FM or band radios like truck drivers used. As far as I know police still communicate on a unique frequency, but today they have other ways to communicate too. I don't think they could 'patch through a call' made to the police station and then to their car. But it's fun to look for these things in the show.
shareAdam-12 (1968-75) always had to stop and use a police phone call box for police business or pay phone for personal calls while on duty.
shareYes they did, was even in shown in TV Shows like Andy Griffith, basically it all goes back to 1946 when the first Mobile Car Phones were used.
http://www.wb6nvh.com/Carphone.htmSo because it was part of the already existing Police Radio set-up and just adding a handset to it, they could patch through to any Police car.
INTRODUCTION:
http://www.wb6nvh.com/MTSfiles/Carphone1.htm
The first car telephones connected to the Public Switched Telephone Network in the United States were put into service in 1946, as a response to the growing mobility of the American population in the postwar years. Initial design of the mobile telephone itself was undertaken by the Western Electric Corporation, the prime supplier of telephone sets to the nation's Bell System operating companies, while Bell Laboratories itself designed the overall system and set the specifications for the equipment. At the same time, the independent telephone companies were developing their own equipment, to be supplied by Automatic Electric. The Bell System equipment built upon an already existing mobile radio set, Western Electric's 1945 vintage Type 38 or 39 VHF FM police radio equipment, adding a telephone style handset and a selective calling decoder, which rang a bell in the automobile when that phone's unique number was signaled.
http://www.arrl.org/phone-patch-guidelinesshare
Radio amateurs in the US enjoy a great privilege: The ability to interconnect their stations and repeaters with the public telephone system. The wisdom of the federal government in permitting, and even in defending, this freedom has been demonstrated time and again. There is no way to calculate the value of the lives and property that have been saved by the intelligent use of phone patch and autopatch facilities in emergency situations. The public interest has been well served by amateurs with interconnect capabilities.
The technology used for 2-way radios is different than what is used for what was originally car phones and now cell phones and landline phones are different still. The information you found is interesting and you'd think it would be easy to find some article stating the difference between them all, but I'm pretty sure you couldn't 'patch a call through' from a landline call to a 2-way radio. I did find out where that term originated - it was from the original switchboards where they would literally connect 2 calls with cables called patch cords using a patch panel.
shareI think the term sought is the nature of the difference between half and full-duplex communication.
https://en.wikipedia.org/wiki/Duplex_(telecommunications)
If one Google’s phone patch schematic, the ubiquitous 600 ohm isolation transformer most often forms the basis for landlines. It’s probably best to think of a 2-way radio more as a 1/2-way radio, i.e. say ‘over’ when done. Cop radios are not full duplex, but with VOX (voice operated relay)/squelch and tone control, the transmit and receive functions can be made more seamless. Phone patching has been around since radio, what has changed is the level of automation in replacing the operator having to manually flip a TX/RX switch, rules can apply. Early car phones were half-duplex-- 2-way, meaning switching. Full-duplex relies on a wide enough split frequency for isolation and power as not to swamp the receiver for simultaneous transmit and receive, think cell and cordless phones.
In an area like L.A. at that time FM-VHF Hi-band equipment was established and likely had repeaters networked with dedicated landlines to extend and define coverage. Phone patch tech became mature quickly with the advent of DTMF or Touch-Tone beginning in the early 60’s. DTMF chips are easy to find now. "ANI" (automatic numeric identification) a unique sequence of tones is common now to identify an individual unit, some shows add that effect for realism. ANI reduces issues with squelch/VOX only setups when more than one operator keys the repeater at the same time causing a heterodyne squeal and missed transmissions.
Phone patching isn’t that high tech, amateur radio and even citizen band operators have done it for decades, rules apply. Tech-wise the wattage used in 2-way half-duplex radio is unlimited as is range, the full-duplex nature of a cell or landline seems to be causing the confusion, hopefully I haven’t added. If there is an art to it, it’s in the method(s) to switch between transmit and receive transparent enough for conversation. Usually at a set attack-hold-release VOX timing both ends adapt to. For me, portraying full-duplex conversation over a 2-way radio, parallels plots that turn transmitters into receivers to see who did the bugging, switch viewer to suspend mode.
The car phone of the 40's was a different beast though, as the article says: " The Bell System equipment built upon an already existing mobile radio set, Western Electric's 1945 vintage Type 38 or 39 VHF FM police radio equipment." To which they were patching through on, like I said even used it on shows like The Andy Griffith Show (1960) which were of that time, it is also how they patched landline calls through to ships at sea.
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