Gizmodo: A Brief History of Listening In on Police Radios

blantonl

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Excellent article here:


Enjoy.
 
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"Anyone with an ordinary receiver at home could tune in and hear the calls at WDKX, at 1684 on the AM dial,” author Christopher Bonanos wrote, of the NYPD, when it started broadcasting to its police cars in the 1930s.

Growing up, we had an old AM Radio in a wooden case that had POLICE at the top of the dial.

Nice article!
 

cmdrwill

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Herschel Calvert was the father of Police Radio. As a Ham radio operator in the 30's - 40's and a motorcycle officer for the Pasadena Police department in California, built the first AM transmitter for Police. .
 

Hfcomms

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Brings back memories. My first scanner was a 10 channel Regency I believe around the 1979 era. Had a blue metal case and you took to cover off to put the crystals in. Ran it off a cigarette lighter plug in the car and had a small wet cell 12v battery if I wanted to use it inside. Worked pretty decent from what I can remember.
 

RFI-EMI-GUY

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"The UK has simply outlawed the use (but not ownership) of radio scanners altogether."

Do they still make people get license to watch TV?
They outsourced the harassment of folks who own "computer monitors" to a private firm that has no police powers. That firm will drag the local constable (who is often confused) into the picture to gain entrance to what often turns out to be a TV set plugged into a video game console.
 

RFI-EMI-GUY

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86785

86784

The above from the Bearcat 210 manual linked in the article. I did not recall the 467 MHz interstitial channels as having existed back then
 

nd5y

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One of the better researched and written articles about our hobby. You can tell that the reporter really did a great job researching the topic.
I quit reading when I got to this part:
The first police radio scanners of the early seventies were practically useless by today’s standards, as users needed to purchase a tuning crystal for each frequency. (An older radio technology, the crystal, typically a tiny piece of lead sulfide, acts as a diode which allows the alternating current caused by radio waves to pass through in only one direction, modulating and smoothing the audio signal, essentially deciphering the sound. Here’s a good explainer from a 1944 issue of Popular Mechanics.)

The link is about AM crystal detectors which has absolutely nothing to do with the local oscillator crystals used in old style scanners.
Gizmodo should stick to writing about smart watches.
 

Alain

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Interesting subject. I'm enclosing a few snips from my own Bearcat 210...with owners manual, which I still own and yes, it still works! It was my first "scanner", but not my first VHF/UHF "receiver". That was a tuneable radio that I received for a HS graduation present. Kuhn Electronics [I believe they were based in Cincinnati] used to manufacturer a tuneable, tabletop radio, its enclosure was made from 1/2' plywood[!] with actual glow-in-the-dark tubes! As an option, you could purchase the telescoping antenna for it, which mounted [via mounting bracket] to the radio. It had a rather large loading coil at its base and the radio performed very well indeed in my apartment. It served me very well during the 1967 Newark [yup, that Newark] riots in July, 1967.

For the radio's particulars, see the link: Kuhn 357C Radio

For those who've scanned as far back [in years...no decades] as myself, you might recall the "Tune-A-Verter" that was manufactured out of Refugio, Texas in the early/mid 1960's. It came in 3 models, lo VHF 30-50 Mcs, hi band VHF, 136-172 Mcs, and the aircraft model from 108-136 Mcs [see photo below]. It was powered by a 9 volt battery in a small compartment on the rear. You could also purchase an optional squelch unit that fastened to the underside of the converter with 4 sheet metal screws.

I used to travel the streets of Newark in my 1966 Pontiac Tempest; you could attach the Tune-A-Verter by unplugging your car's radio antenna cable and inserting a small jumper to the rear of the car radio, then the car's antenna to the rear of the converter.

Lastly is my Bearcat 210. When you purchased the 210 [$170 as I recall, you could call a 1-800 number and reach "Betty Bearcat" You could then request a sheet of frequencies for your local zip code [see enclosed]. I got mine from a Speigel catalog [in 1977]. As I said, it still receives and I have some of the local fire freq's loaded in it. It's a bit worse for wear [in the garage for the past 22 years], but it still functions. Thank for the walk down Memory Lane! Here's the pics:
 

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RFI-EMI-GUY

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Interesting subject. I'm enclosing a few snips from my own Bearcat 210...with owners manual, which I still own and yes, it still works! It was my first "scanner", but not my first VHF/UHF "receiver". That was a tuneable radio that I received for a HS graduation present. Kuhn Electronics [I believe they were based in Cincinnati] used to manufacturer a tuneable, tabletop radio, its enclosure was made from 1/2' plywood[!] with actual glow-in-the-dark tubes! As an option, you could purchase the telescoping antenna for it, which mounted [via mounting bracket] to the radio. It had a rather large loading coil at its base and the radio performed very well indeed in my apartment. It served me very well during the 1967 Newark [yup, that Newark] riots in July, 1967.

For the radio's particulars, see the link: Kuhn 357C Radio

For those who've scanned as far back [in years...no decades] as myself, you might recall the "Tune-A-Verter" that was manufactured out of Refugio, Texas in the early/mid 1960's. It came in 3 models, lo VHF 30-50 Mcs, hi band VHF, 136-172 Mcs, and the aircraft model from 108-136 Mcs [see photo below]. It was powered by a 9 volt battery in a small compartment on the rear. You could also purchase an optional squelch unit that fastened to the underside of the converter with 4 sheet metal screws.

I used to travel the streets of Newark in my 1966 Pontiac Tempest; you could attach the Tune-A-Verter by unplugging your car's radio antenna cable and inserting a small jumper to the rear of the car radio, then the car's antenna to the rear of the converter.

Lastly is my Bearcat 210. When you purchased the 210 [$170 as I recall, you could call a 1-800 number and reach "Betty Bearcat" You could then request a sheet of frequencies for your local zip code [see enclosed]. I got mine from a Speigel catalog [in 1977]. As I said, it still receives and I have some of the local fire freq's loaded in it. It's a bit worse for wear [in the garage for the past 22 years], but it still functions. Thank for the walk down Memory Lane! Here's the pics:
I discovered that the LO from my Bearcat 210 was easily used as a stable synthesized signal generator for tuning other receivers and filters.
 

RFI-EMI-GUY

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I quit reading when I got to this part:
The first police radio scanners of the early seventies were practically useless by today’s standards, as users needed to purchase a tuning crystal for each frequency. (An older radio technology, the crystal, typically a tiny piece of lead sulfide, acts as a diode which allows the alternating current caused by radio waves to pass through in only one direction, modulating and smoothing the audio signal, essentially deciphering the sound. Here’s a good explainer from a 1944 issue of Popular Mechanics.)

The link is about AM crystal detectors which has absolutely nothing to do with the local oscillator crystals used in old style scanners.
Gizmodo should stick to writing about smart watches.
I went right past that on first read. Yes, the technology journalists have no clue. I remember years ago, before advanced CDMA cellular phones (PCS) were marketed, some Wall Street technology "expert" downgrading Qualcomm because their Eudora e-mail client wasn't as great as he expected. The clown had no idea what the company was really about. I made a ton of money holding onto that stock.
 

rivermersey

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In 1921, the Detroit Police Department became the first police department in the country to utilize radio dispatch in their patrol cars. A historical marker at Belle Isle Park describes the new advancement in technology. Between 1921 and 1927, radio buffs Kenneth R. Cox, Walter Vogler and Bernard Fitzgerald, all Detroit police officers, experimented with radio sets they had Installed in the back seat of a Model T Ford police patrol car.
 

jgorman21

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Great article!

From our first tunable Wards Airline 5 band radio, through the first Electra Bearcat crystal controlled (one equipped with speech inversion scrambler/encoder), several others, and up to the software controlled scanners- then onto the Unication “G” series pagers we have seen a lot.

i remember my Aunt’s Father telling me stories about being one of the first dispatchers for the Albany NY PD over AM radio. Saying something like: “we weren’t always sure that they got the calls. Reception was “iffy” and really it was only one way communication!”
 

Archie

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It was a well researched and written from an obvious radical who likely was never born nor lived in NYC during the bad old days. She forgot to mention speech inversion and when we only had crystal scanners that was just fine with most of us. Additionally, it is not likely Samsung and AT&T smartphones will everyone replace VHF UHF public safety radio systems. My separate posting yesterday yielded comprehensive responses from many.
Happy Weekend to all.
 
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