Batboard

Once again, I'm new to Motorola, but I need to pick your brains.

We have an application for emergency situational use of a portable repeater, BDA or some other product that will allow us to boost in building signal coverage on our simulcast system so fire fighters will have better coverage inside a highrise building. It would have to be portable, easy to set up and essentially extend the in building coverage in a crisis situation.

I would appreciate any and all ideas. We don't have to look at Motorola if you know of another product but they will get our first look.

Thank you.

I think most of the firefighters on the board here will agree with me when I say you should NOT be using any trunked/simulcast system while 'on scene' during a fire. You should have a system in place (applicable radio programming, field personnel & dispatcher training, etc) to use simplex comms between the on-site incident command center and anyone inside a structure. This removes the system from the equation, and the less complex on-site comms are, the better. I do believe this is strongly recommended by the various fire/emergency associations in North America. The command center can relay any pertinent information to dispatch/whoever on your actual system. This eliminates the need for any type of BDA or repeater...if the people inside the structure can't reach a portable right outside, chances are they can't hit a repeater either.

Todd

I'm gonna agree on that. Simpler is Better. Unless you have a very good reason for not wanting it, a simplex fireground channel is your best bet. The site commander will be the link between fireground and dispatch which keeps the dispatch channel clear for new business and the 'big picture'. Are you currently licensed for other frequencies? How big is the municipality? if it's a big town, maybe you should get two frequencies. That way you can have FG-1 and FG-2 in case you have two working fires at the same time.

Thanks for the replies guys. We have sufficient channels and utilize simulcast for all scenes and alarm numbers. However, the radios are programmed with talk around for every channel should they have a critical event without simulcast coverage. There is a move to require BDA's of some kind in the zoning requirements of the urban district, but until that inner building coverage is attained we need to research some kind of mobile coverage expander just in case. We are trying to be proactive.

The locality is a major city with very good RF saturation coverage. Unfortunately there are things you must plan for in advance, and underground tunnels, parking garages and multistory basements are the ones we are concentrating on. Until BDA's are zoned we need to have a solution that the district chiefs or scene commanders can roll out in short order.

Once again, we are trying to think ahead. Primary and secondary lines of communications are covered, now we are contemplating the what if...

What you could do is to work out with the System Admin. a dedicated frequency that you could utilize in a repeated mode that would be standalone/portable that is licensed to the area.

As you advised you already have a trunked sumulcast system that you do use, and what you could do is to either:

a. use one of the channels that typicially doesn't get assigned, i.e the channel that transmits the CWID or reserved for control, or

b. request that the System Admin disable a channel in the network during the critical incident if its long term.

I don't think you should veer away from an already licensed frequency, as you would get better protection from interference while you the coverage of you "home system". The possibility of co-channel interference would be reduced greatly than if you used something that may be shortspaced to someone else.

BDA systems generally require some engineering to implement, as the configuration is different depending on the building. You are generally looking at a 'donor' antenna & cable, and possibly multiple leaky feed lines being run for in-building coverage...all while trying not to interfere with what's going on with the system 'on the outside'. I don't think you're going to find any real workable portable BDA solution. So really, portable vehicular repeaters are what you're looking for. Futurecom makes a very nice unit (the Mobexcom II) which fully integrates with either a W4 spectra or MCS2000 III to provide in-band repeating while linking to whatever system you're working with. Pretty slick system, really. Our local FD has tested them over the last 18 months or so, and will soon be installing them in most fire apparatus in the next few months (18 different stations). You can check them out here:

http://www.futurecom.com/mbx_nf.htm

Todd

To add to the fray: in Boston, the BFD began pushing larger buildings to install BDAs to cover the four BFD operating channels. Lo and behold, these devices began leaking their client signals outside the building, bringing up other buildings' BDAs and generally causing all sorts of havoc.

The advice that fireground comms should be handled on direct is sound. As an alternative, BFD normally leaves the fireground repeated (with some training that if a guy is in trouble and no one answers him, he can try direct from his portable), but the Mobile Command Post is dispatched to all working fires. The MCP includes 8 CDM single channel radios, which listen to all four output frequencies and all four input frequencies, via a Zetron 4010R, and it is manned by a regular fire alarm operator. This pretty much guarantees that no transmission from the fireground will be missed. The MCP also serves as the post of the designated Net Chief, a District Chief from another district who is dispatched for the sole purpose of accounting for companies and members.

my dept just made the switch from vhf lo to uhf and havent really got all the kinks out of it. What we do is go to talkaround on the scene, if the repeater is not reachable. Our engine's have pyramid repeaters that go to uhf over to the low band. this is also the secondary means of comms when needing to talk to command.

Excellent answers all. Thank you for the information.

Wave, that was exactly what I was looking for. Thank you.

Coing from a area that pretty much all my 1st due boxes are hi-rise I can feel the problems you might get with communications. Some things we have done recently seem to be working pretty well and others not so well.

They have installed some leaky cable in the subways which works pretty well. There are some dead spots and it's borken into zones so someone could end up talking to another repeater and not the one they need.

For hi-rise stuff. Tried Cross band repeaters with not much luck. So now the SOPs pretty much come down to. Ops on the Fire Floor will be on the primary HT 2watt freq. People in the lobby and other places don't need to hear everything. A chief then sets up at the diffrent locations like Lobby, fire floor, and search and evac post above the fire. They will use a 40watt portable radio to make the link between each of them and take control of the fire. So far this system seems to be working.. No repeaters to fail and no in house equipment to deal with.

Remember one thing- NFPA doesn't want repeated radio communications for fireground operations. If someone gets injured and had no communications through the repeater, there could be a heap of problems here.

Note though that the use of repeated channels on the fireground (i.e., field units xmit on input and listen on output, and Fire Alarm xmit on output and listen on input) is considered OK under NFPA 1221 if the mobile command post, listening on both input and output, is located at or near the fire scene.

Bingo RKG. They intend to roll up on scene and monitor both.

Just don't underestimate the magnitude of the commitment, both hardware and manpower, to meet this commitment.

I agree with the other replys, I don't think I've seen many departments that don't have a simplex channel for firegorund communications.

Here in New Brunswick most VFD's are on VHF and have a common fireground channel (151.3850) since the provincial government won't put up a provincial fire radio network, but thats a rant for another time...