Scanners?

[cruiseroutfit]

Trunking is just a rotating frequecy bank right? I was chatting about scanners with our local HAM outlet awhile back. He led me to beleive that scanners are going to be a thing of the past in the coming years... already in Salt Lake, several of the larger police departments have gone to 100% digital systems. According to him others will be following suit shortly?

When I'm out in the rural parts of the state I still pickup alot of communications on my 2M. I'm in St. George this weekend and have been listening to the local dispatch all afternoon

 

[gary in ohio]

Trunking is just a rotating frequecy bank right?
already in Salt Lake, several of the larger police departments have gone to 100% digital systems. According to him others will be following suit shortly?

Trunking is not just rotating freq bank, Is more like a cellular system. There are bunch of towers, each tower has a set of frequencies. Instead of channels you have trunk groups. (which act like channels). If I am on trunkgroupa my radio talks to the controller and I am give a freq, EVERYONE else on trunkgroupa is give and frequency as well, These may be the same or different frequency depending on where the radio is located. The system then makes sure that all the audio on trunkgroupa is send to all "logged in " radio that are on trunk groupa. The system manages frequencies, sometimes each transmission you get a differeent freq, sometimes you stay on the same.

Going digital is not the same as going encrypted. A 100% digital system can still be heard if you have a digital capable scanner. Encryption is still pretty expensive and most agencies can hardly afford the radio's on digital system. $3-8K/radio compared to $1000 for a analog radio. encryption runs another grand or more.

 

[taugust]

If you want it all, go with a digital trunking scanner. Bearcat or others. Expect to pay about $500. For a non-digital trunking scanner, about $250. Digital trunking will get police an sheriffs. Analog (Non-digital) trunked will allow you to get most other agencies, fire included. Some fire agencies are still use non-trunked, conventional frequencies. I don't know it they have CB channels. You can program in NWS channels, but your ham radio may have those channels preprogrammed. I have a Uniden Bearcat BC246T Analog Trunk Tracker III. Works great but I can't get local sheriffs Dept. who are on digital trunking. Trunking is just a means of sharing a limited pool of frequencies so each agency doesn't have to be assigned their own freq. It works great until a disaster can overload the system.

Tim
KG6WFV

 

[adrenaline503]

Encryption has lots of different sounds and some of them are distinctly different from standard digital modes.

DES sounds like white noise and you'll usually hear a beep when the transmitter is unkeyed.

OTAR sounds like when you pick up an old POTS modem. This is used to update the encryption keys on trunked radios.

Motorola trunked DES sounds like a combination of stuff, like garbled white noise.

KY57/58 sounds like digital noise that almost has a non-random pattern. You will hear the transmitter unkey.

F1 mil voice encryption sounds like someone holding an unplugged guitar amp cord.

VIS sounds like people talking, but like you're running a vinyl record backwards. This encryption is what Gary is most likely talking about, it sounds like a made up language when you listen to it.

How in the world do you know all that? Pretty cool.

 

[gary in ohio]

Digital trunking will get police an sheriffs. Analog (Non-digital) trunked will allow you to get most other agencies, fire included.

what you get depends on where you are and what they are using. In some cities there are all digital, others analog. Ohio has a state wide digital network and most state agencies are on that system, Police in the big cities are on trunked analog, Out in the country where I am at the sheriff are running simple repeater based systems.

 

[NorCalSam]

Thanks, Gary!