Don’t Skimp on Coax — Link to a Good Loss Chart

3:45pm Thur.

When trying to work farther on SSB/CW bands like 50, 144, 222, 432, 902 and 1296 MHz your coax or feedline is important.   To make these 200, 300 mile contacts, (farther with band enhancement) you want every last db you can get.   A few db may be the difference between no signal and good copy (with headphones) in the S1 range.   You don’t want to wimp out on coax.   Here’s a link that shows the loss characteristics with various coaxes.   http://www.therfc.com/attenrat.htm   I found these links by Googling “coaxial cable loss chart”.
Some will say that it’s not worth getting concerned about a few db’s.   I’d say that any way you can improve your system by at least 1 or 1.5 db, you will notice an difference with marginal signals on weak-signal V/UHF.  You start gaining a few db’s with a better yagi, plus a few db’s with better coax, use a good preamp, quality headphones… it adds up quickly.
Main point is that while cheap coax may be OK on HF, it will seriously degrade your signal on VHF/UHF.  If you’re going to the trouble of putting up good antennas, then don’t throw away your signal with cheap coax.   If you have coax runs of 70-100 feet, you want to be at least in the 9913 or LMR-400 range, especially above 2 meters.   If you have a run of more than 100 feet, (especially on 432 MHz and higher) then LMR-400, 600 or perhaps even hardline is necessary.

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