Yeah, really good question, Rick... I think it's a matter of both frequency and what cable you're using, i.e. how much loss you're getting. A Really Long Run of RG-8 may be several hundred feet or so for HF, but only 100 feet at VHF, and 10 feet at 1.2 ghz. If the loss is enough to matter, or if you need to spend a lot more money on coax, then it's a Really Long Run.

A 3db loss, for most applications, is about where you can just detect a difference. Don't forget to add in a little for the connectors. It's a classic "half an S-unit" on receive, and the loss of half your power on transmit. So, 100' of RG-8 type coax may be ok for VHF, but starts becoming a problem at UHF and above. I.e. it's starting to become a long run for UHF.

At least, that's how I would sum it up.

Greg KO6TH

Rick wrote:

I keep seeing all these remarks referencing a "long run"... What is considered a long run above VHF? 50 feet, 100 feet, something in between? At what point should we be using 9913/LMR-400 coax or LDF4 hardline?

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