"Rob" wrote in message
...
I am finally going to put up a VHF antenna for 2 meter and another antenna
for 70 cm.

What is type of coax should I use? Rg213? Or will RG213 be too lossy?

Recommendations please...

Rob



Simple. Use the lowest loss coax you can afford.

Dan/W4NTI

Have fun - use twin-lead 300-ohm or ladder-line 450ohm...
use a half-wave u-shape balun + a 1/4-wave stub on each end - and your runs
can be pretty long without a lot of loss - or a lot of expense.


"Rob" wrote in message
...
I am finally going to put up a VHF antenna for 2 meter and another antenna
for 70 cm.

What is type of coax should I use? Rg213? Or will RG213 be too lossy?

Recommendations please...

Rob




---
Outgoing mail is certified Virus Free.
Checked by AVG anti-virus system (http://www.grisoft.com).
Version: 6.0.690 / Virus Database: 451 - Release Date: 5/22/2004

Hal Rosser wrote:
Have fun - use twin-lead 300-ohm or ladder-line 450ohm...
use a half-wave u-shape balun + a 1/4-wave stub on each end - and your runs
can be pretty long without a lot of loss - or a lot of expense.


I'm afraid this is largely a myth from the Olden Days. Back then,
twin-lead was probably better than most types of coax that hams could
buy... but coax has improved, and twin-lead hasn't.

The myth has been overly influenced by a few measurements dating back to
the 1950s, made under ideal conditions that can't be achieved in real
installations.

The reality is that twin-lead is difficult to install, sensitive to
electrical disturbances, of very poor quality if it's also low-cost, and
*very* sensitive to getting wet. The higher in frequency you go, the
more each one of these things matters.

(Yes, I know there are a billion TV sets out there using twin-lead - but
that doesn't make it right. Most viewers in the USA have been
brainwashed to accept appalling standards of TV picture quality.)

Parallel-line can be excellent for power distribution and phasing
*within* a stacked array. I've used it on the moonbounce array at
432MHz, in a wet climate, but those were short, straight lines that are
self-supporting with mostly air insulation - a completely different
thing.



"Rob" wrote in message
m...
I am finally going to put up a VHF antenna for 2 meter and another antenna
for 70 cm.

What is type of coax should I use? Rg213? Or will RG213 be too lossy?

Recommendations please...

As many others have said, it depends how important low loss will be for
*your* particular application.

If a significant length is involved, and you're interested in weak
signals, then RG213 (full quality, no substitutes) should be your
minimum specification.

People in the USA can recommend specific brands that will be available
to you.



--
73 from Ian G3SEK
'In Practice' columnist for RadCom (RSGB)
Editor, 'The VHF/UHF DX Book'
http://www.ifwtech.co.uk/g3sek

Ian White, G3SEK wrote:
Parallel-line can be excellent for power distribution and phasing
*within* a stacked array. I've used it on the moonbounce array at
432MHz, in a wet climate, but those were short, straight lines that are
self-supporting with mostly air insulation - a completely different thing.

Given a single dipole, multi-band antenna, parallel transmission line
is just about the only choice. The 50 ohm SWR on a one-wavelength
dipole is about 100:1. The 500 ohm SWR on a one-wavelength dipole is
about 10:1. Under those circumstances, it is no contest.
--
73, Cecil http://www.qsl.net/w5dxp



-----= Posted via Newsfeeds.Com, Uncensored Usenet News =-----
http://www.newsfeeds.com - The #1 Newsgroup Service in the World!
-----== Over 100,000 Newsgroups - 19 Different Servers! =-----

I am finally going to put up a VHF antenna for 2 meter and another antenna
for 70 cm.

What is type of coax should I use? Rg213? Or will RG213 be too lossy?

It depends on what you wan to do . As mentioned use the lowest loss you can
afford. The 5/8 inch hard-line is great but not many will want to pay the $
5 per foot and about $ 70 per connector and put up with the stuff not being
easy to bend.

Look at the LMR 400 or Belden makes some that is hard to find I think is
called 9914. It has almost the same low loss as the 9913 but uses a solid
dielectric instead of the hollow type of the 9913. If you are only using 30
or 40 feet and mostly the FM repeaters, the RG8x type is ok. As someone
mentioned the RG 6 type sold for cable TV is fine for a run of 50 feet or
so. The on;y problem is the connectors. IT is 70 ohm coax but for most
simple systems it will not mater.

I have used most all of the above but the hard-line at home and it all
depends on what I was doing. I only want a few local repeaters for a rig in
the house so a homemade dipole (vertical) is up about 25 feet on the tower.
It has about 40 feet of rg59 and then about 30 feet of rg58 going to it.
Not the best but it works fine for what I am doing. I also have a 2 meter
ssb rig in the shack that is fed with the 9913 and it seems to work ok for
it. Using a dual band antenna to a scanner that is programmed with 2 meter
and 440 repeaters and feeding it with about 100 feet of rg8x. The 2 meter
part works great but not so good on the 440 band.
The satellite antennas are feed with the 9913 and sofar I have been able to
keep the water out of the coax.

Cecil Moore wrote:
Parallel-line can be excellent for power distribution and phasing
*within* a stacked array. I've used it on the moonbounce array at
432MHz, in a wet climate, but those were short, straight lines that
are self-supporting with mostly air insulation - a completely
different thing.

Given a single dipole, multi-band antenna, parallel transmission line
is just about the only choice. The 50 ohm SWR on a one-wavelength
dipole is about 100:1. The 500 ohm SWR on a one-wavelength dipole is
about 10:1. Under those circumstances, it is no contest.

Very true... but also a *very* long way from the original question.


--
73 from Ian G3SEK 'In Practice' columnist for RadCom (RSGB)
http://www.ifwtech.co.uk/g3sek

On Sun, 30 May 2004 10:44:15 -0400, Rob hath writ:

I am finally going to put up a VHF antenna for 2 meter and another antenna
for 70 cm.
What is type of coax should I use? Rg213? Or will RG213 be too lossy?
Recommendations please...

Cable TV Hardline. You can't beat the price. HI!HI!

http://jonz.net/W3DHJ/catvhardline.html

73
Jonesy
--
| Marvin L Jones | jonz | W3DHJ | OS/2
| Gunnison, Colorado | @ | Jonesy | linux __
| 7,703' -- 2,345m | config.com | DM68mn SK

Ian White, G3SEK wrote:
Cecil Moore wrote:
Given a single dipole, multi-band antenna, parallel transmission line
is just about the only choice. The 50 ohm SWR on a one-wavelength
dipole is about 100:1. The 500 ohm SWR on a one-wavelength dipole is
about 10:1. Under those circumstances, it is no contest.

Very true... but also a *very* long way from the original question.

Too bad English is not a context-free language, huh?
--
73, Cecil http://www.qsl.net/w5dxp



-----= Posted via Newsfeeds.Com, Uncensored Usenet News =-----
http://www.newsfeeds.com - The #1 Newsgroup Service in the World!
-----== Over 100,000 Newsgroups - 19 Different Servers! =-----

"Old Ed" verbositized:

Hi -

Just curious: Do you know of any (reasonably priced) vendor that
offers 9913 conveniently made up in standard lengths, with connectors?
(CPX1318 is available in that form.)

WHAT is a Standard Length?

And, do you want to trust factory installed cheap connectors?

Even if coax comes with connectors, I take those off and install my
own, so I know it was done right and will last.

TTUL
Gary

Go on ebay and get yourself some 1/2 andrews hardline.
Ends are not much money for N, so239 are more pricey.

If you cant, get some LMR400.

www.cablexperts.com are good people.


On Sun, 30 May 2004 10:44:15 -0400, "Rob" wrote:

I am finally going to put up a VHF antenna for 2 meter and another antenna
for 70 cm.

What is type of coax should I use? Rg213? Or will RG213 be too lossy?

Recommendations please...

Rob