Hi Tony, the problem with cheapo RG58 is there ain't much screen!! If you
have a fair amount of span up it does stretch under its own weight. I have
used all sorts of wire. My top wires are very thin single strand pvc
covered. I did this in the premise that the current flowing in the flat top
doesnt radiate it has "passed through the radiation resistance" (the
vertical part) so any resistance here doesnt matter and it will be small
compared with ground losses. I have some 16swg enammelled (not for any good
reason....it just came that way) Dont rely on rope as insulators it is
likely to catch-fire at higher powers (It is usually at a voltage point)
Some good "eggs" in series of even pyrex if you can find em are worthwile
for powers obver about 50W. The main thing is use a wire that will support
itself. On long spans telephone "dropwire" has been used This has steel
strands and a couple of copper ones......being just part of the capacitive
load it resistance downt matter.
Whilst coax would give a bigger diamerer and a bit more capacity a couple of
spaced wires will be better and probably cheaper.
Probably contentious but it's like the people who insist you need Litz and
Litz coils. Practical tests show that it makes very little difference in
amateur style systems. Yes Litz does give a lower loss coil but you can do
as well by making sure you get the form factor right (length and diameter
very similar) and the final "Q" is about 10% lower....this is totally
swamped by the effcets of ground losses and environmental (to nearby
structures or tress) losses.
.....some of my best aerials were made from old copper wire salvaged from
old low voltage transformers !! The problem there is they are only usually
shortish lengths.
Alan
----- Original Message -----
From: "Tony Baldwin" <[email protected]>
To: <[email protected]>
Sent: Thursday, June 24, 2010 4:10 PM
Subject: LF: Antenna wire
Sorry to ask a stupid newbie question but what is the best wire for my
aerial ?
I had thought about getting a couple of 100m rolls of cheapo RG58 and
soldering the centre and screen together, or is there a better way ?
Tony, EI8JK
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