Quote:
Originally Posted by D. Stussy[_2_]
"Ralph Mowery" wrote in message
m...
I would like some opinions as if anyone could notice replacing 100 feet of
rg-213 with 7/8 inch or larger hardline would be noticiable.
One ham said when he did he could tell the differance. I just don't see
that going from about .4 db or less of loss to .15 db of loss on 80 meters
is going to be noticed. That is about like going from 100 watts of
transmitted power to maybe 105 watts or less.
In the past I have inserted some 1 and 3 db pads in line with a receiver to
see if I could tell the differance and have a hard time telling that even
the 3 db pad makes much differance in casual operation, especially below 20
MHz. Maybe some have more sensitive ears than I have.
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For HF, RG-213 vs. hardline makes no significant difference. The frequency
of the transmission is low enough that the heat loss is barely measurable.
I only use hardline on my 2.4Ghz or above feeds or where the power into the
line exceeds 250w. Otherwise, it's LMR-400, except for 222Mhz and
receive-only operations still using RG-58.
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I think that some of the posts has gone off target on this one.
Simple math tells us that as long as the op is only wanting to compare power in vs power out and signal in vs signal out that he should be using Belden 9913 F7 or LMR 400 coax.
You wouldn't or couldn't use hardline for a dipole antenna, maybe for a beam antenna, if you were going to attach the hardline to the side of the tower or to a track. The Hardline would be too heavy to support with a rope.
RG 213 is not a very good coax from my perspective - especially if you want to get maximum performance out of a piece of coax.. At higher frequencies you are throwing away a proportional amount of signal in the coax and a proportional amount of power loss between the transmitter and the antenna.
If you were building a repeater, you would want hardline going up the tower to the antenna, regardless if it was 6 meters, 2 meters or 70 cm..
If you were trying to work rare DX on either of those bands, you would want to use the best possible coax with the lowest loss, and if you went to the expense to put up a tower and a stacked beam antenna array to work those bands, you would want hardline to feed those antenna's..
That is the purpose of hardline - not to feed a HF antenna!