Coax for field kits

[flashover52]

I’m assembling some mobile radio kits for an emergency communications group. I will be using Wouxon KG-1000g Plus radios, Laird FG4603 antennas mounted on 20’ telescoping poles and MFJ-1921 tripods.

 

I want to have a 25’ and 100’ length of cable in each “field” kit (or maybe 50’ & 75’) so LMR400 is going to be a bit too stiff. These could be set up in a building and pass cable out a window, in a large tent used by a large incident Incident Management Team or operated out of a vehicle on a ridgeline.

 

I have a 300’ pool of rG213 I could cut, though it seems bulky. I was thinking of LMR240 but had someone mention that it’s not great for GMRS frequencies.

 

Anyone have any suggestions?

[gortex2]

LMR240 for 25' would be suitable. At 100' you need LMR400. 

I have a  VHF Search and Rescue Repeater. I swept the cables. We use LMR400 for 30' jumper and when we use the 60' its 1/2" LDF. Yup its bulky but it works well. 

 

Remember at 100' thats just about 3 db (2.7) of loss. Thats half the power you put in and 3db receive less. 240 is 5db of loss at 100. I wouldn't even consider it. 

[tweiss3]

How do you plan on carrying this "field kit"? If it's in a trailer and you have room to mount large coils on the wall or in a drawer? The reason I ask, my HF kit for the field has 20' of RG-8x, which is pretty bulky if you are going to carry it. For UHF, beyond having the radio connected directly at the push up mast, you will need at a minimum LMR400, and probably hardline, like the 1/2" LDF mentioned above. Going to 1/2" hardline reduces your loss at 100 feet from 2.7 to 1.5, which is huge.

[flashover52]

The plan is to put the radios n Pelican cases. I was hoping to have everything except the antenna/tripod in the case.

We have a repeater that provides excellent coverage of our city. Heck, I can hit it from my house a couple counties away (-45 miles). So in the city we have the repeater that most HT’s can ping. The main focus is if that repeater is down, then we have a simplex plan. I already have VHF/UHF ham radios at these sites. We are adding the GMRS radios to support the AREs folks and distribute traffic.

Sounds like I may need to leave the coax out of the case, bite the bullet and go with LMR400.

How durable or long should I expect it to last if it’s getting unrolled/rolled a couple times per month?

[BoxCar]

The main point will be to keep short bends out of the cable body and use some sort of boot or strengthening at the connectors. If your are truly worried, use an ultra-flex cable but you still need to protect the connector ends.