Batboard

Hello,
I am putting together an EOC and need to run some coaxial. What is the best type?

If money is no object, go with 1/2 inch Heliax. Connectors are expensive as well. Try not to use adapters.

Next might be RG214, the military stuff with silver-coated braid and center contact. This is 0.405 inch diameter.

RG400 is smaller than RG214 but usually has the same specs. This is 0.195 inch diameter. It has a bit more loss than RG214.

Bob M.

It depends on how far you really have to go and if your running through conduits, a plenum, or up a tower.

Give us some more details on the installation and we can give you better answers.

Problem with RG214 is that it has higher losses than you think. You would do better to use some LMR-400 if it is not used for duplex service. Otherwise bite the bullet and put in the 1/2 inch or 7/8 coax heliax type cable.

Do it once and you don't have to worry about it again for many years. Just make sure you weather seal all the connectors and ground the whole thing.

Jim

kcbooboo wrote:If money is no object, go with 1/2 inch Heliax. Connectors are expensive as well. Try not to use adapters.

Next might be RG214, the military stuff with silver-coated braid and center contact. This is 0.405 inch diameter.

RG400 is smaller than RG214 but usually has the same specs. This is 0.195 inch diameter. It has a bit more loss than RG214.

Bob M.

We are going to be using RG8, Thanks for all of your help. We are running from an office outside the office to the chimney (15'). we are also running from the office through the wood to the other side of the building (45'). We are unsure of the connectors at this time.

The one thing you didn't stae is the frequency
RG8 shouldn't be in your vocabulary if you are using 700/800Mhz

VHF and UHF 453.

If you had already made your decision to use the worst stuff possible, why did you even bother asking for anyone else's opinion?

Bob M.

rg8, worst stuff. Interesting. I was told it was the best stuff. Please explain

RG8 is suitable for HF stuff just fine. Many hams tell, and have even told me, that RG8 is the super super best. - Wrong. Sure, for around 50MHz and below, but above that ins't the best choice due to the loss factors.


I would stick with heliax above that. And for your project being an EOC, in an emergency I would want to be using the best stuff you money can buy.

I'd use Andrew LDF4-50. It's fairly expensive, but you don't want to cut massive corners for a public safety application.

LDF4-50 from the polyphaser to the Antennaa
FSJ4RN-50B (Plenumn rated superflex)from the poyphaser to the unit.
Don't spare the grounding.
I guess it depends on what sort of use your EOC is for.
Are you in a hurricane, tornado, serios storm area?

Don't forget providing LIGHTENING PROTECTION!!!
You need to protect both your radios and building when using
ANY outside antenna. A grounding system for the radio room and
Grounding of the coax along with the use of some type of coax
Suppressor, for the center pin, of the coax need to be included in your budget.
Ground that suppressor also. Remember, a close strike by lighting can destroy most modern radios and computers unless they are protected. I mention computers, because computers connected by wired LAN systems can be damaged also. The LAN wiring can act like a long wire antenna and conduct the EMP of a large close strike.

mm

Jim202 wrote:You would do better to use some LMR-400 if it is not used for duplex service.

I use it all the time in duplex service. Just make sure to use the approved connectors for it and it works fine. 99% of the time I use Crimp N connectors and have not had a problem with it.

Kurt

Give it time. the problems will show up. Mother nature will show you just how well this cable works after some time outdoors.

Jim

n1pfc wrote:

Jim202 wrote:You would do better to use some LMR-400 if it is not used for duplex service.

I use it all the time in duplex service. Just make sure to use the approved connectors for it and it works fine. 99% of the time I use Crimp N connectors and have not had a problem with it.

Kurt