Radio System Problems/Possible Solutions

[JChabalie]

Hello all. I don't post on here often, but I do peruse these forums often and it seems like there are some very knowledgeable people on here. I am looking for some input. My fire department, as well as 11 other departments were just recently moved from our old wideband dispatch channel to a new narrowband dispatch channel. We, as well as a few other departments, are experiencing some pretty bad coverage issues. We have reported the coverage issues to our county dispatch center and they say they are investigating, but we are trying to come up with some possible solutions to recommend to them to help render our situation.

A little bit of background on myself. I am currently the fire captain at my department and I have 9 years of experience in the fire/ems service. I have been a 911 dispatcher (police, fire, and EMS) for a neighboring county for 4 years. I also have experience in radio programming and some radio technologies.

Our area: we are located in Washington County, PA which is in Southwestern Pennsylvania about 25 miles south of Pittsburgh. We have a lot of hills and valleys in our area and a mixture of rural/suburban with some light industrial.

Our old channel worked very well for us and the other departments that were assigned to it. It was a relatively simple system. Just one stand alone repeater at a good location in our area to provide coverage to everyone that used it. If I am not mistaken, our 911 center communicated with us via a control station.

Our new channel has 3 transmitters/receivers located in different areas of our "zone" of the county (not on our old tower location that worked well). One would think that this would improve coverage, but it has done pretty much the opposite.

The problem: There are a lot of issues with reception in our areas. Depending on which tower our signal is hitting, based on our location, other units that may be in a different area (ie: still responding, station monitoring, etc) cannot receive their transmissions or updates. We can hear one tower fairly well, another one is very sporadic and not reliable for us at all, and the 3rd we can't hear at all in our area. The issue we are told is that because of how the system "votes" the transmissions, there is not much that can be done as far as us being able to hear other units. In order for 911 to talk to us, they have to manually select which tower to transmit on. If they transmit on the wrong one, we may not hear their message. Our tones are preset as to which tower they go out from. Coverage was so bad that they had to program our tones to transmit on 2 different towers.

Some solutions that we are considering:
1. Reprogram our old repeater on our old tower to receive our current dispatch channel and retransmit it on a new channel. If I am thinking correctly, this should receive the 3 towers and then retransmit it so we are able to hear it better. I'm not certain if this is a good solution from a technical standpoint, but my thinking is it should work.
2. Reprogram our old repeater to the same transmit/receive frequencies as our current channel, but have a different transmit pl, thus forcing our transmissions to go through this tower. This would help us be able to hear our units, but it would still not solve the overall issue of coverage.

The best solution, in my opinion, would be to set up our system as a simulcast system, similar to what we have in the county I dispatch for, so that all transmissions are heard, no matter where you are in the area. The problem with this is, I have been told our county doesn't believe in this kind of system and they don't believe it works.

Anyway, just looking for some feedback as far as what may or may not work to help our situation. Any input would be greatly appreciated. Thanks in advance!

[fineshot1]

Not knowing the exact technology, configurations and the lay of the land the best
thing I could recommend is for you to find a local communications consultant to do a survey
and analyze that data and have them do some of the collected data modeling so they can
recommend professional solutions. Asking here on RR this for a possible solution is not the
way to go.

[R8000]

I would suggest you go through the chain of command within your county to address the problem. If it's a county owned system, then they need to address it.

However, what may seem like a cool idea such as making a repeater for a repeater, and simulcast comes into legality of licensing and money.

Simulcast is super expensive...that is if you want it to actually work. A fly by night radio shop can slap up some transmitters that are kind of in phase and it will work but sound like crap, or you can have a radio shop that knows what they are doing and have it sound great.

Narrowbanding does reduce coverage. There are many arguments about how much it reduces coverage but we can play it safe and say...yes you will have less coverage.

I would suggest letting the county deal with it, and go through the proper channels to have your concerns addressed. Not all radio systems are perfect and many times it may appear your E911 director is dropping the ball or the radio shop sucks, when in reality the E911 director asks for funding and is denied by county board members.

I see this all the time, old crotchety county board members calling shots and they think the low band motrac is a fine radio and sees no reason to invest any money into the system *sigh*.

It sounds like to me your county would benefit from a multi site simulcast/voted system.

I build analog simulcast systems, and they are pricey but when done properly...you can't even tell it's simulcasted. I get complaints all the time from people who live outside the intended simulcast coverage area saying it sounds bad. A properly engineered simulcast system will work good in the area it was intended for. out side of that area..such as out of county, then yes it will sound bad the farther you get away from it.

interoperability ??? Ummm...analog FM simplex meets that need, and is cheap and simple

[JChabalie]

Thank you for the information. We have been having good communication with our County, reporting our concerns to them and they seem willing to help. We were just tossing around some ideas that we thought could help.

I would love if they would be able to do the simulcast system. The county I work for has their systems set up that way and they work great. You can literally talk from one end of the county to the other on a portable and hear each other perfectly. On the system my FD is on, I can't even get out a mobile at times.

Oh well. I guess we will just wait and see what, if anything the county will do to render this. Its just frustrating to feel like you are stranded per say when on a call because you don't know if your radio will work or not. Thank you guys.