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RG58a/u vs RG8x
- Thread starter Coyoteman
- Start date
I wouldn't use either, get some lmr240 from times microwave and save yourself in the end. JMO. God bless.
At that length you won't notice the difference on 11 meters and barely on 2/70@cm.
I replaced 18ft of rg8x in my bronco with 20ft of rat shack rg58, didn't notice any difference what so ever.
Since the price difference is minimal why not get the better coax or even get better still with LMR240 or LMR400. Coax cable is usually the cheapest part of an installation especially when you only need 20 feet of it. Other than a few interconnecting jumpers I use nothing less than Belden 8214 and even some of that is used as pigtails for my Andrew LDF4 heliax.
CB frequencies according to Times Microwave data:
20 feet of RG-58: 0.5 dB or 5.6% in losses
20 feet of RG-8X: 0.4 dB or 4.5% in losses
20 feet of LMR-240: 0.3 dB or 3.4% in losses
2 meter frequencies...
20 feet of RG-58: 1.1 dB or 11.9% in losses
20 feet of RG-8X: 0.9 dB or 9.8% in losses
20 feet of LMR-240: 0.6 dB or 6.7% in losses
70 cm frequencies...
20 feet of RG-58: 2.0 dB or 20.6% in losses
20 feet of RG-8X: 1.6 dB or 16.8% in losses
20 feet of LMR-240: 1.0 dB or 10.9% in losses
I know there are those that obsess over losses, but even the largest difference between the coax types shown in the 70 cm ham band won't make enough of a difference that you would notice it. Generally speaking it takes about 3.0 dB or around 50% before you would notice the difference, and that is only if the person on the other end was watching the s-meter directly. I have also seen many duel band antennas for 2 meters and 70 cm and almost all of them came with RG-58 on them, and the ones I've used, typically for repeater work, mind you, made no difference whatsoever...
Note, if you substitute a third rate coax, such as the coax sold at Radio Shack, for the Times Microwave coax numbers above, you results may vary...
The DB
20 feet of RG-58: 0.5 dB or 5.6% in losses
20 feet of RG-8X: 0.4 dB or 4.5% in losses
20 feet of LMR-240: 0.3 dB or 3.4% in losses
2 meter frequencies...
20 feet of RG-58: 1.1 dB or 11.9% in losses
20 feet of RG-8X: 0.9 dB or 9.8% in losses
20 feet of LMR-240: 0.6 dB or 6.7% in losses
70 cm frequencies...
20 feet of RG-58: 2.0 dB or 20.6% in losses
20 feet of RG-8X: 1.6 dB or 16.8% in losses
20 feet of LMR-240: 1.0 dB or 10.9% in losses
I know there are those that obsess over losses, but even the largest difference between the coax types shown in the 70 cm ham band won't make enough of a difference that you would notice it. Generally speaking it takes about 3.0 dB or around 50% before you would notice the difference, and that is only if the person on the other end was watching the s-meter directly. I have also seen many duel band antennas for 2 meters and 70 cm and almost all of them came with RG-58 on them, and the ones I've used, typically for repeater work, mind you, made no difference whatsoever...
Note, if you substitute a third rate coax, such as the coax sold at Radio Shack, for the Times Microwave coax numbers above, you results may vary...
The DB
It all depends on who made yhat rg/58 that came with that dual band antenna too. Losses aren't all there is to consider with coax either. Shielding is a big factor. Like I said the price difference is tiny. Get the better coax for all the difference in price.
My mobile radio used to get iPhone generated screen noise interference when I had my K40 antenna and magmount and the iPhone sitting on the passenger seat. Now since I had swapped thr K40 out for a Sirio antenna and magmount I only get iPhone generated screen noise when I bring my iPhone to the edge of my car's roofline. That proved to me that all coax isn't created equal unless someone can give a better explanation for that phenomenon.
I would say who makes the coax is far more important than what type it is, most is cheap chinese imported cable and copper content is low, RG58a/u is no longer a mil spec, Rg 58C/U with tinned conductors replaced it years ago and since then all RG58 type cables have come under the M17/28 standard, look for RG58c/u with a Mil-C-17 F or G stamp or M17/28 stamp, that way you can be sure its mil spec, any letters before Mil-c-17f are older and been lying about a while so have probably passed their shelf life.
Rg8x I wouldn't give the time of day too, its not mil spec and if it ain't good enough for uncle sam it ain't good enough for my radio.
I use either 100m of CRT France RG58 C/U with M17/28 stamp (exact same cable found on Sirio mag bases) and Mil-C-17f stamp or 2x100m (328 ft) military surplus ITC/BELDEN RG223 with a M17/84 stamp that is genuine and cost me a 1/4 of the retail price of £300 on e bay.
Rg223 is a RG58 cable that has silver plated conductor and dual silver plated braids, If it wasn't for getting them cheap I wouldn't have bothered as RG58c/u is plenty sufficient, but some things are too good to let go, inferior stuff sells here for £2 a metre,
I also have URM67, a British Standard RG213/U Equivalent made by Uni Radio, now Webro if I'm not mistaken.
If it doesn't have the proper stamps on it and if it says RG58 "type" or any other rg type its not real mil spec,avoid it .Guarantees good quality conductors and shielding.Proper Mil Spec is the way to go, if its good enough for your military its good enough for your CB
.
Times Microwave LMR range or SSB electronics Aircell/Ecoflex ranges are good too, but not necessary for a 20ft run, its doubtful if you or anyone on receiving end will notice a difference, make sure you use a good antenna, that is the key to success, add mil spec coax and proper amphenol plugs or ps gland alternatives if your not confident of soldering braid, you won't go far wrong.SSB electronics do high quality ps gland plugs too.
Good quality coax,plugs, and good soldering (not as easy as many think, preparation is essential,especially on Nickel plated plugs, pretinning conductors is essential for a good joint) and a damn good antenna are the path to consistent success.
Rg8x I wouldn't give the time of day too, its not mil spec and if it ain't good enough for uncle sam it ain't good enough for my radio.
I use either 100m of CRT France RG58 C/U with M17/28 stamp (exact same cable found on Sirio mag bases) and Mil-C-17f stamp or 2x100m (328 ft) military surplus ITC/BELDEN RG223 with a M17/84 stamp that is genuine and cost me a 1/4 of the retail price of £300 on e bay.
Rg223 is a RG58 cable that has silver plated conductor and dual silver plated braids, If it wasn't for getting them cheap I wouldn't have bothered as RG58c/u is plenty sufficient, but some things are too good to let go, inferior stuff sells here for £2 a metre,
I also have URM67, a British Standard RG213/U Equivalent made by Uni Radio, now Webro if I'm not mistaken.
If it doesn't have the proper stamps on it and if it says RG58 "type" or any other rg type its not real mil spec,avoid it .Guarantees good quality conductors and shielding.Proper Mil Spec is the way to go, if its good enough for your military its good enough for your CB
.Times Microwave LMR range or SSB electronics Aircell/Ecoflex ranges are good too, but not necessary for a 20ft run, its doubtful if you or anyone on receiving end will notice a difference, make sure you use a good antenna, that is the key to success, add mil spec coax and proper amphenol plugs or ps gland alternatives if your not confident of soldering braid, you won't go far wrong.SSB electronics do high quality ps gland plugs too.
Good quality coax,plugs, and good soldering (not as easy as many think, preparation is essential,especially on Nickel plated plugs, pretinning conductors is essential for a good joint) and a damn good antenna are the path to consistent success.
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