Hi Joe, the link below is for a coax calculator. its self discribatory, it will let you see the difference the various coax's have agains each other vs freq. The hight you go in Freq, the lossier the cables are. Two good barometers are to run comparisons on 2m and 400 mhz. ie. 144, and 432 Mhz, 100ft runs leave the 100 watt input the same and watch the watts out !. that will give you a really good idea of cable loss. now you can see why I recommended some RG213 over the RG58 you're running now. you are losing over 50% of your power to the cable loss. that's way to costly for operation performance. We all cut corners but there are some things not to cut and running "a good" not necessarily the best feed lines out there is a good thing to get in the habit of. and a good cable will last you your lifetime almost. Ok have fun with the calculator. de Ellis WA1RKS