Ok I've got one for all you experts.. I belong to our county CERT team, and we are purchasing a new response trailer to replace the one that we currently have as it is too small. We have also applied for and expect to receive a decent grant to (among other things) buy new radios to replace the ancient/inadequate Motorola Talkabout FRS radios we currently use. Since I'm the only licensed ham and real tech nerd on the team they looked to me to come up with a workable radio solution. I have some ideas but there's some things I'm not sure about and want to be sure (and make sure I'm not missing anything) before I bring them my plan.
The idea has been floated to simply buy a few P25 radios and get a talkgroup on the statewide system (KSICS), but I honestly don't think this will be the most efficient use of the money because we would only be able to get five (there are over a dozen members on the team). We have also been deployed out of state before - which means the radios won't be able to hit KSICS towers, and if we are sent to an area in state where the KSICS tower has been damaged, we'd have the same issue.
That said, here's what I'm thinking of...
I propose we get a business band license for nationwide full-power initerant frequencies (since we never know where we will use them). I believe we are classified as government (we operate under FEMA and the county Emergency Management) so we should qualify for full exemption of fees.
I think the Motorola RDU4160D UHF radios would fit our needs (high power, water/dust IP, long battery life, digital readout for channel).
I also propose we install a repeater in the trailer to increase range if needed. I was looking at a 50W VS VXR-9000 with duplexer. The antenna would be on a 7-33' Geroh crank-up mast attached to the front of the trailer.
The trailer would have a bank of AGM deep cycle batteries to power everything (including lighting, flashlight/phone chargers, inverter, etc) in the event shore power and the generator were not available, and an RV-style power panel with DC converter/charger.
Now here's the questions I have..
First, there is also a 50W 2m/70cm mobile in the trailer, and its antenna will also be mounted on the crank-up mast (we may also get a P25 mobile to connect with emergency departments if funds allow). There will be a T-bar at the top to accommodate the multiple antennas, and I know about the proper separation. What I am concerned about is the feedlines. I intend to use LMR-400, but there will need to be a minimum of two, possibly three leads, and they will need to be able to accommodate the extendable mast. Will there be any cross interference running the lines exactly parallel to each other over the 60' or so I would need to make that coil? Also it has been a while since I ran mine, so I need to know if LMR-400 will hold a "coil" shape - so if I fabricate a "bowl" at the bottom, can I ziptie the leads together and make a coil that will follow the mast and keep itself organized? Or do I need to sleeve it in Nycoil to keep it neat? Should the leads be choked?
Any issues with flexing the cable in this installation?
I'm also thinking of putting 3-4 12V LED floodlights on the mast. Will there be any issue including the power cables in this coil?
Anyone have any opinions on the VXR-9000? Better alternatives in the same price range? It would have to be able to run directly from 12V, not just as a backup how like the 7000 works.
I think thats all I have right now but I may need more info later..
Thanks!
The idea has been floated to simply buy a few P25 radios and get a talkgroup on the statewide system (KSICS), but I honestly don't think this will be the most efficient use of the money because we would only be able to get five (there are over a dozen members on the team). We have also been deployed out of state before - which means the radios won't be able to hit KSICS towers, and if we are sent to an area in state where the KSICS tower has been damaged, we'd have the same issue.
That said, here's what I'm thinking of...
I propose we get a business band license for nationwide full-power initerant frequencies (since we never know where we will use them). I believe we are classified as government (we operate under FEMA and the county Emergency Management) so we should qualify for full exemption of fees.
I think the Motorola RDU4160D UHF radios would fit our needs (high power, water/dust IP, long battery life, digital readout for channel).
I also propose we install a repeater in the trailer to increase range if needed. I was looking at a 50W VS VXR-9000 with duplexer. The antenna would be on a 7-33' Geroh crank-up mast attached to the front of the trailer.
The trailer would have a bank of AGM deep cycle batteries to power everything (including lighting, flashlight/phone chargers, inverter, etc) in the event shore power and the generator were not available, and an RV-style power panel with DC converter/charger.
Now here's the questions I have..
First, there is also a 50W 2m/70cm mobile in the trailer, and its antenna will also be mounted on the crank-up mast (we may also get a P25 mobile to connect with emergency departments if funds allow). There will be a T-bar at the top to accommodate the multiple antennas, and I know about the proper separation. What I am concerned about is the feedlines. I intend to use LMR-400, but there will need to be a minimum of two, possibly three leads, and they will need to be able to accommodate the extendable mast. Will there be any cross interference running the lines exactly parallel to each other over the 60' or so I would need to make that coil? Also it has been a while since I ran mine, so I need to know if LMR-400 will hold a "coil" shape - so if I fabricate a "bowl" at the bottom, can I ziptie the leads together and make a coil that will follow the mast and keep itself organized? Or do I need to sleeve it in Nycoil to keep it neat? Should the leads be choked?
Any issues with flexing the cable in this installation?
I'm also thinking of putting 3-4 12V LED floodlights on the mast. Will there be any issue including the power cables in this coil?
Anyone have any opinions on the VXR-9000? Better alternatives in the same price range? It would have to be able to run directly from 12V, not just as a backup how like the 7000 works.
I think thats all I have right now but I may need more info later..
Thanks!
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