Question about FCC's policies...

[rrbum]

I noticed a license recently granted to my local fire company. Several frequencies for mobile use but only one for FB2. Upon entering the base freq I immediately heard DMR bursts. Wondering why a license for analog voice is emitting digital bursts I looked for who else may be licensed on the frequency. Much to my amazement, a private trunking radio outfit has a transmitter within two miles of the fire company's base station.
How can they grant permission when the frequency is already in use in the same area? Am I missing something? How can these two systems co-exist without detrimental effects to one or the other?
Any help understanding would be appreciated.

 

[RadioGuy7268]

List up the call signs and frequency in question.

Generally speaking, a true trunked system in the UHF or VHF bands should have exclusivity. If the private outfit with a trunked system doesn't show as a "YG" with FB8 designation, then the trunked system is supposed to monitor for activity, and block any transmissions while other users are on the channel. Some people call that "psuedo trunking" or scan based trunking.

There can be sharing agreements and arrangements in place that will over-ride the rules, or create special exceptions.

The "official" FCC rules for PLMR trunking are in 90.187 - and they have made changes in the past year or so to clarify some of the rules.

 

[rrbum]

Interesting, never heard of the "pseudo trunking". I doubt that is what is going on here though.
But here are the particulars...

Frequency: 461.3500 Mhz
Fire Co. callsign: WQTR733
Trunking callsign: WQLT921

 

[ecps92]

Well the Business had been there since 2010

Did anyone listen before applying for the Frequencies ??
I would go back to your Frequency Coordinator and complain to them, which ought to be fun as the people who did your FCC filling is the same company as the trunking system

CommPaths, LLC
Kelly Arnold
233 Race St
Philadelphia, PA 19002

Also you are licensed on Business Frequencies, Not Public Safety
Business users must share the channels, which are usually more loaded than Public Safety

I noticed a license recently granted to my local fire company. Several frequencies for mobile use but only one for FB2. Upon entering the base freq I immediately heard DMR bursts. Wondering why a license for analog voice is emitting digital bursts I looked for who else may be licensed on the frequency. Much to my amazement, a private trunking radio outfit has a transmitter within two miles of the fire company's base station.
How can they grant permission when the frequency is already in use in the same area? Am I missing something? How can these two systems co-exist without detrimental effects to one or the other?
Any help understanding would be appreciated.

 

[RadioGuy7268]

Interesting, never heard of the "pseudo trunking". I doubt that is what is going on here though.
But here are the particulars...

Frequency: 461.3500 Mhz
Fire Co. callsign: WQTR733
Trunking callsign: WQLT921

OK - looking up the WQLT921 License on the FCC's database most of the frequencies listed are FB6 - but there's one which is listed as an FB8 - 452.73125. That frequency is the linchpin for his system. He would home all users on the FB8 - and then trunk or switch traffic over to the other frequencies when the home channel is busy.

The rules as I understand them say the FB6 channels would need to be set up to monitor for activity, and disable usage for those channels if another co-channel user is transmitting. Nothing stops them from trunking to an idle channel.

Do you hear the trunked system talking over top of your operations (when your people are actively involved in conversation) ?

As another poster mentioned, those are Industrial/Business frequencies, not public safety. Those channels are shared with other users.