I've used DavisRF and also bought coax locally.
http://www.davisrf.com/ham1/coax.htm
has an attenuation table. At 100ft, maybe you lose 3dB at 30Mhz with
the RG58.

I'm not as concerned about loss as much as will the cable hold up
outdoors, and the quality of the shielding.

There are attenuation charts on the net.
Robert11 wrote:
Hello:

Will be putting up an outdoor Listening-Only antenna. (30 MHz, on down)

After the outdoor Balun and Lightning Arrestor, it looks like I will need
pretty close to
100 feet of coax to get it to the receiver.

Can anyone suggest what might be the lowest cost coax that will not exhibit
any "meaningful" attenuation for listening only at around 30 MHz ?

I don't have a good feeling on how to evaluate the db losses for the
individual types with regard to
what is, and is not, meaningful for listening.

Don't mind spending another 50 cents or so per foot, but would like to not
do it
unless it would really offer an improvement.

Also, guess I would like the smallest diameter possible, but this, of
course, would be a secondary consideration

Is the Wireman Company: considered a reputable, and good, source for ?
Others ?

Might as well also ask this while I'm at it:

re those metal mesh Kellums for supporting a wire- If placed over the active
antenna wire (not the coax), is there any "shorted-turn" effect phenomenon
to be considered ?.

Thanks,
B.

wrote:
I've used DavisRF and also bought coax locally.
http://www.davisrf.com/ham1/coax.htm
has an attenuation table. At 100ft, maybe you lose 3dB at 30Mhz with
the RG58.

I'm not as concerned about loss as much as will the cable hold up
outdoors, and the quality of the shielding.

RG-6QS quad shielded satellite dish coax. The shielding is better than
most small diameter 50-ohm coax. The impedance of RG-6 is 75-ohm but
that's not an issue for HF reception. Radio Shack sells a 100-ft roll
for $35.

http://tinyurl.com/e3wn3