FCC Rule Question "Linking"

[r60]

With the proliferation of Trunking systems in New Jersey, I have seen a marked increase
in linking these systems to a single stand alone UHF\VHF frequency.

The intent is clearly to be able to listen to the system with a non-trunking radio such
a fire pager.

Would anyone care to opine on the legality of these full time links?

How does it comply with the rule on a user’s ability to monitor before transmitting?
Clearly this does not have a chance happen.

Would a co-channel user be able to file a complaint and be successful?

902?

[W2NJS]

PS agencies that have converted to 800 mHz trunked systems commonly retain their legacy UHF or VHF systems in operation to transmit dispatch operations for the benefit of interested persons who do hot have receive capabilities for the trunked system. In my home area this is done by several FDs. Any co-channel stations are located so far away, and with different PLs, that it's not a problem. It's legal because the agency is obviously licensed for the legacy channel. You will find all kinds of exceptions to the FCC band plans. In Montgomery County MD 153.95 was their primary fireground channel on simplex but was also licensed for repeater operation on the local subway system. It remains in operation today as a legacy channel and I've heard it used for comms with medevac helicopters from outside the area, just to cite one example. We also have a fixed, commercial station on 151.625 which is a grandfathered operation licensed to American Towers. As I said, exceptions to rules are not uncommon.

[robbinsj2]

I don't think the question was about authorization to use the selected frequency, but ability to use it while complying with other regulations (specifically, not interfering with co-channel users). Whether by necessity, accident, or intent co-channel users here sometimes don't have the luxury of geographic separation. Different PLs alleviate the problem only a little bit. (Anybody else local remember Hillsborough fire's relay on the Bridgewater-Raritan school bus input frequency? That got past the frequency coordinator.)

I'm bemused by these links, and the implementation of some trunked systems in the area. I understood the two biggest advantages of trunked systems to be spectrum efficiency and interoperability. Take Franklin as an example:

- No users other than police have access to any of the police channels, even in receive-only.
- Police very rarely switch to other channels to communicate directly, messages are almost always relayed through dispatch, and this sometimes involves two different dispatch centers.
- Nearly all the legacy base/repeater channels have been retained in use. This includes Police 1, Police 4, Fire 1, Fire South, Fire D1, Fire D3, JEMS-1. By my count the only base/repeater channels relinquished are Fire-North, two DPW channels, and the squad repeater.
- Districts 2 and 3 have added conventional UHF repeaters to help their operations.

So what is really the benefit of this trunked system? It gets everybody radios which can also have access on the county's trunked system, which is a very good thing. The police have more effective channels and better coverage, and municipal services have more channels. Fire, EMS, and DPW are using about as many talkgroups as they had conventional channels before, and fire/EMS could talk together on VHF as well.

Other specific things which have surprised me from various towns/ systems:
- ALS and BLS using the same trunked system and same dispatch center, but using two different talkgroups even when responding to the same call. (This isn't volunteers mustering, this is the ALS truck and the BLS ambulance on the road and/or at the scene.)
- Fire service removing all EMS "tactical" talkgroups from their radios, keeping only the EMS dispatch channels.
- One town's emergency service radios not including the its county's standard tactical (conventional) channels so on-scene interoperability involves borrowing radios.

</rant>

Jim