WHAT TYPE OF PAGING IS THIS?
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WHAT TYPE OF PAGING IS THIS?
IN OUR AREA WE USE MOTOROLA TYPE II. OTHER SURROUNDING DEPARTMENTS ON THE SAME SYSTEM ARE BEING PAGED OUT WITH WHAT SOUND TO BE 4 DTMF TONES AND THEN ONE OF THE THREE ALERT TONES ARE SENT TO IDENTIFY THE NATURE OF THE CALL. DOES ANY ONE KNOW THE NAME OF THAT TYPE OF PAGING, 4 DTMF TONES EACH TONE IS AROUND 250MS.....?
If it's not actual DTMF, you're probably hearing the old 2+2 format, a.k.a. Motorola Quik-Call I. This was used to trip the old fire and air raid sirens, and worked with the Plectron boxes.
2+2 was viewed as a more secure way of encoding than just sending two single tones. The "tags" (sweep sirens, beeps, warbles, hi-lo, steady 1000 hZ tones) after the 2+2 tones are just attention getters. They serve no electronic decoding purpose.
With all the digital stuff on the market, 2+2 is now considered antiquated technology. I don't know of very many systems still on the air. The Zetron Model 25 is the only encoder I know that can still do these tones.
More info: http://www.policeinterceptor.com/emerg.htm
Rick
2+2 was viewed as a more secure way of encoding than just sending two single tones. The "tags" (sweep sirens, beeps, warbles, hi-lo, steady 1000 hZ tones) after the 2+2 tones are just attention getters. They serve no electronic decoding purpose.
With all the digital stuff on the market, 2+2 is now considered antiquated technology. I don't know of very many systems still on the air. The Zetron Model 25 is the only encoder I know that can still do these tones.
More info: http://www.policeinterceptor.com/emerg.htm
RickYEAH I AM FAMILIAR WITH THE 2+2 IF IT HELPS ATLANTA FIRE ALSO USES THIS TYPE OF DTMF PAGING. http://WWW.SCANFULTON.COM
THANKS FOR THE INPUT
THANKS FOR THE INPUT
Well, in all fairness he said it sounded like 4 DTMF tones 250 ms each in duration then an attention tone and then said in a second post it was like that of Atlanta.
Sounds to me like they use the DTMF tones to open up the PA system at the appropriate fire houses instead of all of them at once. Columbus uses a separate radio channel around 950 MHz and I think they use sub-audible signalling to open up PA receivers in fire houses. If I remember right, all fire runs air at all stations and EMS runs are aired to zones. It's been awhile since I've listened to it. As far as your area, it's probably something similar.
Sounds to me like they use the DTMF tones to open up the PA system at the appropriate fire houses instead of all of them at once. Columbus uses a separate radio channel around 950 MHz and I think they use sub-audible signalling to open up PA receivers in fire houses. If I remember right, all fire runs air at all stations and EMS runs are aired to zones. It's been awhile since I've listened to it. As far as your area, it's probably something similar.
It's been years since I've heard Columbus's system, but what you describe is what I remember. The original poster was from New Carlisle, and, at one time, one of those southwest Ohio counties used 2+2. Licking County (Newark) did too for fire paging, and maybe still does. I thought that may have been what he was hearing.