How critical is quality of coax

prey · Post by **prey** » Monday 16th Jul 2007, 5:39

I've finally gotten everything I need to hoist my IMax 2000 24 ft. vertical up to 37 feet at the base and expect it to endure a storm. I do not, however, have enough of the big, thick $2 per foot coax I've been using to reach this new height. I do have a length of the cheesy Radio Shack $.50 per ft., thin-looking 52 ohm stuff to suffice. Would I really notice a difference in performance either way? I hate to dismantle the entire antenna just to have to screw on better coax directly to the antenna whenever I can afford it. I'm not worried about losing actual transmit wattage (I'm ok on that) and couldn't I just crank my RF gain up a tad to compensate for a bit of loss reception-wise? I mean, it's not going to selectively filter out signals more than background noise...?
Is this non-ideal coax not nearly as much to worry about as getting up high in the air, period?

TrumpyNZ · Post by **TrumpyNZ** » Sunday 16th Sep 2007, 1:52

If you only want to do the job once, I'd recommend RG-8 or RG-213 coax.
The old saying goes, you get what you pay for.

King Mudduck · Post by **King Mudduck** » Monday 17th Sep 2007, 4:50

Coax is VERY important, it will make or brake your radio setup! Think of it this way. If you were to build an 800hp BB Chevy and then try to supply fuel to it with the stock full line and fuel pump how well do you think it would run?

I don't know if this link will work but here it is. It will take the guess work out of coax!

http://www.ocarc.ca/coax.htm

booger351 · Post by **booger351** » Wednesday 2nd Apr 2008, 16:11

I don't think you will notice much performace difference, although cheaper coax is less shielded and might result in your radio bleeding through tvs and phones ect, and may be more likely to recieve interferance from power lines and other rf noise.
As far as performance, rg-8/u (the thin stuff) has a loss factor of 1.2db at a length of 100ft on 50mhz, and loss factor is less than that on 27mhz cb, and if you are going up 37feet and use 50ft of coax it would cut the loss even more, the worst I see on my chart is rg-58 and it has a loss factor of 4.1db on 50mhz.
I have used radio shack jumpers, and I would reccomend getting some good pl-259 ends and putting them on, I have had there cheap connecters fail more than a few times.

speedracer6g · Post by **speedracer6g** » Sunday 1st Jun 2008, 7:36

Your Coax and antenna is the most important part. I would recomend using rg8. Cushcraft makes a reasonably priced Coax that has very good specs. there are many manufacturers of coax and prices and specs vary. one spec you want to go by is db loss per 100ft. here is some specs on the stuff i use. Notice it has only .8 db loss/100ft @50MHZ.

http://www.tessco.com/products/displayP ... ventPage=1

I have about 240ft left from an install if you need some.

MIKE

PM me if you want more info.

frogman296 · Post by **frogman296** » Monday 9th Jun 2008, 18:29

i always recommend no less than rg8 or rg 213...the most important part of the system...antenna and feedline...