Rg-58a/u???

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n5ims

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It will work, but not well (especially at higher frequencies) unless the distances are very short (20 feet or less). If you're stuck with that size of coax try some good grade RG-6.
 

W2NJS

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A good grade of RG58 will lose half your signal (3db) when the line is 100 feet long. A cheap grade, of which there are far too many, will lose a bit more, and the loss gets much greater as you go higher in frequency. It pays to use the least lossy coax you can afford, especially is you're doing 800/900 mHz monitoring. All the reputable manufacturers publish the loss of their cable in terms of db per 100 feet, so do some research online and you'll come up with something you can afford which does the job for you. You'll also want to stick with cable that has a MANUFACTURER'S name on it, not a reseller or dealer.
 

zz0468

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A good grade of RG58 will lose half your signal (3db) when the line is 100 feet long.
At what frequency?

At 45 MHz, 100' of RG-58 is 3 db loss.

At 160 MHz, it's 5.8 db loss.

At 860 MHz, it's 14.1 db loss.
 

W2NJS

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Like I said, "...A cheap grade, of which there are far too many, will lose a bit more, and the loss gets much greater as you go higher in frequency. It pays to use the least lossy coax you can afford, especially is you're doing 800/900 mHz monitoring."

Was there something mysterious about my statement? Far as I'm concerned the OP is certainly capable of looking up the loss tables for coax.
 

zz0468

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Was there something mysterious about my statement?
Yes. The frequency.

3db in 100 feet might be ok in some applications, but that same 100 feet is a whole lot lossier for other applications.

Far as I'm concerned the OP is certainly capable of looking up the loss tables for coax.
By now, hopefully he is. But based on the nature of the original post, I'm going on the possibility that no, he wasn't, and therefore asking for advice.
 

mpddigital

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The biggest problem is that the attenuation amounts you are refering to are applicable Only for decient Mil Spec RG-58. Most of the chinese crap ( vast amount of the cheap stuff) will be much worse. If $$ are at a real preium try some RG-11. Most places you should be able to pick up the US made stuff for less than 40 cents a foot. For best results try a Good Quality RG-213 or any of the Times or Commscope LMR types depending on length.

RG as a coax identifier ONLY means it is of a certain size and supposed construction type without any regulations or standards at all for anything not made for Government contract. LMR or CNT . WBC coax types will give you the lowest overall loss for most uses although for a few niche applications 223, 213, 214 and a few others are still better. Good Luck!
 
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