Today it is an almost sure bet that any radio sales person coming in the door to talk with any public
safety agency is going to talk a "P25" trunking system. Like others have said, it is in the salesman's
pocket interest to sell the most expensive system they can. This way their commission can be at the
max. Doesn't matter what is best for the public safety agency, the sales force are going to push the top
dollar system they can get the agency to spend on. Note, that this trunking system may be far beyond
what the agency can afford or even needs.
The radios on the market today are generally able to do P25. There are some that won't and I would
shy away from those. The main name to the game of obtaining a new radio today for VHF or UHF is
to make sure it does come with "digital" ability right out of the box without having to add a feature
software upgrade. The trunking ability on VHF or UHF is a rather expensive option and if you do
choose to go for it, make sure it is a "P25" compatible option.
On the P25 compatibility options, there is some digression by one or two companies to keep pushing
a proprietary functionality here. It either is P25 compatible all the way or not. When you start to hear
some back paddling or the "well, it does this", you need to get very technical and make sure your
getting what you think your getting. Don't take the word of the sales force stuffing the radio down
your throat, get someone on your side to dig into the details and make sure it's what you want.
Motorola is famous for throwing in all these features that an agency will never use and they just
add to the cost. Like right now there are a couple of new trunking systems being installed with
what is called P25 phase 2. This is having more than one conversation going on on the same
RF channel. It also means that you have to jack up your entire radio system and replace it
in it's entirety. Nothing is left except the towers and antennas. It's a very costly upgrade and
leaves all the other agencies around you with no way to communicate with the new system.
Radio system upgrades can be needed by a number of agencies. The big but comes in on
who is writing the specs for the new system. Don't let the radio vendor write the specs. Don't
rely on the radio vendor looking out for the best interests of the public safety agency. Find
someone that has a good solid proven background in radio systems to work with the agency.
It may take bringing in a consultant to help with this. But again, I will point out that there are
consultants out there that are not agency friendly. They are also looking to fatten their own
pocket and will drag out a job or look for ways to jack up the cost of the project. The reason
is these consultants typically base their price of the work based on a percentage of the total
radio system project cost. Walk carefully here and try to get a fixed price for the consultants work.
As for the differences in frequency bands to use, I am an old timer that likes to use VHF. I have
found over the years, that VHF seems to be the best selection for range and getting into buildings.
The problem with VHF is that you really have to dig to find frequencies available. The best you
can do is to monitor the channels and see what activity there is. Do this from the tower sites
with an antenna on the tower at the elevation you will be selecting for your system use. If you find
some channels open with no activity, then do your homework in the FCC database and see who is
currently licensed on the channels. If you do a 30 day test and find no activity, I would put this in
your request to the frequency coodinator and see what happens. The FCC has been reclaiming
channels with little or no activity, even though agencies still maintain a license. You just have to
find a channel and then press to get it licensed.
Hope this adds to some of the answers you were looking for.
