What I've seen as an RG8X is a smaller cable than the old RG8, slightly
bigger than an RG58 and that meets with my description for its shield.
This fact doesn't insure that what I've seen is really the same RG8X
sold or known in the US or that some feature like the percentual of
tinned copper braid may vary depending by manufacturer.
> ---------- Initial message -----------
> From : "Gary J. Ferdinand W2CS" <email@example.com>
> To : <firstname.lastname@example.org>, <email@example.com>
> Cc :
> Date : Thu, 1 Mar 2001 09:41:34 -0500
> Subject : RE: [TowerTalk] Coax Rating
> One of us is confused. I've never seen RG8X with "a thin aluminum
> Foil-Polyester Tape-
> Aluminum Foil and only very few thin copper wires as braid shield."
> RG8X is foam dielectric with standard copper shield and various forms
> jackets depending on manufacturer.
> Here's a URL to Belden's RG8X specs:
> Note the description of the shield as being "copper braid."
> As for power-handling capability, I've seen conflicting specs on that.
> Strictly speaking if the SWR is 1:1, under 10MHz RG8X is spec'd to
> 1500W. By the time you get to 50MHz (yeah, right!) it's down to
> the other hand, those ratings QUICKLY degrade when the VSWR starts
> above 1:1. This thread started with the context of a 3/2 wave
> Such an antenna is not going to provide a 50-ohm feedpoint (or it
> purely accidental if it did, height dependent). Given RG8X's voltage
> of about 300V, practically speaking it cannot handle the legal limit.
> My personal experience with mysterious incidents of shorted feedlines
> RG8X on both 7 and 21 MHz at 700W leads me to believe it's not a good
> for legal-limit usage on any practical antenna system.
> So, I guess I respectfully disagree :) This might be yet another
> what works on paper and what fails miserably in actual use.
> Gary W2CS
> | -----Original Message-----
> | From: firstname.lastname@example.org
> | [mailto:email@example.com]On Behalf Of firstname.lastname@example.org
> | Sent: Thursday, March 01, 2001 8:57 AM
> | To: email@example.com; firstname.lastname@example.org
> | Subject: RE: [TowerTalk] Coax Rating
> | The reason why an RG8X insn't raccomandable at high power levels is
> | because of a shield that's made of a thin aluminum Foil-Polyester
> | Aluminum Foil and only very few thin copper wires as braid shield.
> | The foam dielectric hasn't significant losses and a foam cable of
> | same size of an RG8X, but with a classic copper braid or a more
> | consistent foil (aluminium or copper), would safely withstand much
> | than US legal power at 7 MHz, and roughly twice the power of an RG58
> | expecially at 30 MHz and above.
> | 73,
> | Mauri I4JMY
> | > ---------- Initial message -----------
> | >
> | > From : email@example.com
> | > To : <firstname.lastname@example.org>
> | > Cc :
> | > Date : Thu, 1 Mar 2001 08:35:18 -0500
> | > Subject : RE: [TowerTalk] Coax Rating
> | >
> | >
> | > Ted,
> | >
> | > Be careful. Yes, I have had a meltdown as you call it, using some
> | > hamfest-grade RG8X on a 100 ft run feeding a 1/2 wave on 40. The
> | power into
> | > the feed line was likely about 700W. I don't know whether this
> | happened
> | > while operating on 40 or 15. And here's the caution...you might
> | squeak thru
> | > with a perfectly flat SWR. But with 3/2 waves I'd bet you will
> | have
> | > that. Any SWR will significantly increase the probability of
> | the
> | > line.
> | >
> | > As I recall, the rating is about 300V across that foam dielectric.
> | Less
> | > sure of that than the above. I believe RG58 is actually more
> | forgiving than
> | > RG8X in terms of power handling.
> | >
> | > I'm using RG8 now, with a convenient tree to help support the
> | so the
> | > antenna doesn't have to see it all.
> | >
> | > 73/Gary W2CS
> | >
> | >
> | > | -----Original Message-----
> | > | From: email@example.com
> | > | [mailto:firstname.lastname@example.org]On Behalf Of Ted & Joyce
> | Wilhelm
> | > | Sent: Wednesday, February 28, 2001 11:39 PM
> | > | To: email@example.com
> | > | Subject: [TowerTalk] Coax Rating
> | > |
> | > |
> | > | Am planning on trying to put up 3 1/2 waves on 40mtrs. and
> | if
> | > | anyone knows the maximum power that RG8X will handle on a
> | > | short run less than 100 feet....I know I would probably be
> | off
> | > | with something like 213 or the like but am concerned with the
> | > | factor....Anyone had any major meltdowns using the lighter feed
> | line.
> | > | Thanks,
> | > | Ted K9HUH
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