BCD436HP/BCD536HP: NEWB question: How do I determine a local transmission's frequency?

[unusedusername]

Hello Folks,

I have a BCD536hp that I keep in my trailer to listen to the forest service when we go camping. I've enjoyed playing with it, so I've just picked up a BCD436hp so I can play around when I'm not camping.

I've brought the 436 to my office, and I'd like to figure out what frequencies the security guys are using. I'd prefer to not ask them. They would probably tell me, but I'd rather have the challenge of figuring it out myself.

First, I checked the radioreference db. There is nothing in there for either my company or the security company. I looked up the name of the security company (securitas) in the FCC license DB, and found a few frequencies they registered for. These frequencies don't have any locations though, just "California Statewide". I programmed those frequencies into my 436 (using FM narrow) with Sentinel, however that appears to not be the correct set since I have not had a hit all day today with them.

Next I've tried using the close call feature in the scanner, but I'm not getting very far there either. I turned on filtering for pagers and local FM broadcasts in the menu so I don't get spurious hits, however now close call isn't picking up anything at all.

So, I'm completely sure that this scanner can figure out what I'm looking for, but I'm not sure how to do it. What is the correct procedure for this?

Thanks!

 

[marksmith]

You are on the right track with both procedures.

What you locked out in close call is fine and should not effect anything. Close call is the best way to find what you are looking for.

There is a possibility that they are using a system that cannot be monitored bt the 436. Some security and other types of business use systems other than what the main public safety people do, mainly because it's a little cheaper.

They are in the FCC database. Just a matter of finding them.

Mark
WS1095/536/436/996P2/HP1e/HP2e/996XT/325P2/396XT/PRO668/PSR800/PRO652

 

[RandyKuff]

Interesting thread...
http://forums.radioreference.com/ca...ion-forum/71071-securitas-security-freqs.html

 

[W8RMH]

Contract security commonly uses radio equipment owned and licensed by their clients. Check (the FCC database) for licenses that belong to the company they provide services to, such as the building's owners, management firm, or the company you work for.

 

[UPMan]

Also, if you turn on Close Call and contrive to get one of the guards to transmit while you are a few feet away, the scanner should detect/grab the frequency within a fraction of a second.

 

[I_am_Alpha1]

Or they are leasing radio time from a third party company. Hunting down frequencies can be fun--and frustrating. Another thing--try to find out what radio they have (name, model, what the antenna looks like), as this will give you lots of valuable info. Type of antenna can tell you what band (VHF, UHF, 800, etc). Make and model can tell you what format they are using (P25, DPMR, etc). Also, if you can, listen to what the signal sounds like on one of their radios, if you know what digital vs analog sounds like that is.

My guess, Motorola, 800mhz, DPMR, trunking--but just a guess.

 

[unusedusername]

Marksmith:

Thanks for the encouragement! I enjoy the challenge so I'll keep at it.

Interesting thread...
http://forums.radioreference.com/ca...ion-forum/71071-securitas-security-freqs.html

Interesting, so effectively they might be using cell phones on Nextel (Sprint?). That would explain why the 436 isn't picking them up. Their radios don't look cell-phone-ish though, not that I can really tell.

Contract security commonly uses radio equipment owned and licensed by their clients. Check (the FCC database) for licenses that belong to the company they provide services to, such as the building's owners, management firm, or the company you work for.

I looked there also. I couldn't find any applications from my company

Also, if you turn on Close Call and contrive to get one of the guards to transmit while you are a few feet away, the scanner should detect/grab the frequency within a fraction of a second.

Hrm.... Sneaky! How far away does CloseCall work if they are using handheld radios? If I'm on my office on the 4th floor, will it trigger if the security guys in the control room in the 1st floor key up? I'm effectively directly above them.

Or they are leasing radio time from a third party company. Hunting down frequencies can be fun--and frustrating. Another thing--try to find out what radio they have (name, model, what the antenna looks like), as this will give you lots of valuable info. Type of antenna can tell you what band (VHF, UHF, 800, etc). Make and model can tell you what format they are using (P25, DPMR, etc). Also, if you can, listen to what the signal sounds like on one of their radios, if you know what digital vs analog sounds like that is.

My guess, Motorola, 800mhz, DPMR, trunking--but just a guess.

I'd have to do a bunch of research on radios to do that. I can't identify the different types of commercial radios by sight. For that I'd need to find a security guy and ask him to show it to me.

 

[RandyKuff]

I gave an electrician friend of mine a hand several years ago when he was backed up with work... He used Nextel phones... They had like a walkie talkie type capability too... Might be what they are using...

 

[Voyager]

How far away does CloseCall work if they are using handheld radios? If I'm on my office on the 4th floor, will it trigger if the security guys in the control room in the 1st floor key up? I'm effectively directly above them.

Unlikely. On VHF/UHF, depending on the power level of their radios and the RF environment around you might get 50-100 feet horizontally, and that is not taking metal into account or your vertical separation. They would likely have to be on the floor below you to get a hit.