Anybody got lengths of RG8x or 58A coax?

Im getting ready to install radios (VHF marine and CB) in my sailboats and am needing at least 100-200 feet of the above coax. Looking for cheap prices/swap/trade

Gunner

"At the core of liberalism is the spoiled child, miserable, as all spoiled children are, unsatisfied, demanding, ill-disciplined, despotic and useless. Liberalism is a philosophy of sniveling brats." PJ O'Rourke

Reply to
Gunner Asch
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Gunner Asch fired this volley in news: snipped-for-privacy@4ax.com:

You know it doesn't age gracefully, yes? LLoyd

Reply to
Lloyd E. Sponenburgh

I've got several 35 foot chunks of full sheilded 6 up here in Ontario Canada, but you can buy it in Cali for less than the shipping cost form Ontario Canada.

Reply to
clare

Gunner Asch fired this volley in news: snipped-for-privacy@4ax.com:

Gets a bit leaky, too, and the characteristic impedance changes with age, making it hard to tune into a matched load well.

LLoyd

Reply to
Lloyd E. Sponenburgh

Get marine-rated RG8. The covering is more water-resistant. If it's exposed to sunlight, it will last longer than RG58. And stay away from anything with which you can see the inner insulation through the braid. It will be lossy and it's unlikely to last in a marine environment.

RG58 with a good, dense braid, in the relatively short lengths you'll be using, is likely to perform better than RG8 with a less-dense braid.

Reply to
Ed Huntress

Gunner Asch fired this volley in news: snipped-for-privacy@4ax.com:

RG8 is the better choice of the two. It's usually foam-core, and low-loss. It's also got a little faster (lower) velocity factor than RG58, making it lower-loss over a given length of run.

Ham radio rule-of-thumb: Even with cheap, homebrew antennae, NEVER skip on the feed-line. Use the best you can afford, because most of your operating power losses are there, not in the antenna.

LLoyd

Reply to
Lloyd E. Sponenburgh

Ed Huntress fired this volley in news: snipped-for-privacy@4ax.com:

Yep. I'd agree with that, with the minor exception that almost all of them now use a foil outer conductor, and the braid is more to keep everything tight and conductive than to provide the "shielding" function, as it did in prior times.

But Gunner, he's right. Buy the BEST feedline you can afford for any given job. That's where your power losses will be, and you can't really ever get that power back, even with a so-called "positive gain" antenna. (anybody who actually believes you can feed 12 watts into a 6dB 'gain' antenna and get an effective 50 watts out hasn't really run the math.)

Plus... those losses work both ways, reducing received signal strenght by a similar factor.

LLoyd

Reply to
Lloyd E. Sponenburgh

Premade 100' cables are $20+16/30+10s/h ($36-40 each) on eBay. Got PL-259s and crimpers? Make one stretch.

But, yeah, $5 for a hank of cable would be a much nicer deal. Water seems to be the deciding factor on longevity of the coax. Keep the ends dry and they'll last a long time.

Reply to
Larry Jaques

Larry Jaques fired this volley in news: snipped-for-privacy@4ax.com:

UV affects them, too (not only the 'brittleness' of the sheath, but the plasticizers and solvents that work their way into the core, changing the characteristic impedance). Once IN the mast, that's not a problem (only moisture, then), but how was it stored/kept prior? If it's not virgin cable from a reputable source, you just don't know.

I guess it depends upon whether this is a project to make the boat "sellable", or if it's an attempt to maximize propagation.

Lloyd

Reply to
Lloyd E. Sponenburgh

Would Gunner's short-range use (locally in lakes) make much difference in the effect of an old cable? Impedance tuning usually affects range, right? It has been a long time since I was exposed to much RF chatter (QA @ Southcom, Intl. ca. 1975)

FYI, I ran across an old (Swan?) SWR meter at a Goodwill type store for $2 last October and couldn't let it sit there. I figured that it might come in handy later, in a top-down world.

Reply to
Larry Jaques

Larry Jaques fired this volley in news: snipped-for-privacy@4ax.com:

Maybe not, but if they're ever used as ocean-going craft, it could. People routinely go outside their "range" of either distance or competence.

Why skimp on "the critical link"?

Cable isn't that expensive! (although it can exceed the cost of the load at the end of the run...)

Lloyd

Reply to
Lloyd E. Sponenburgh

A length of 3/4" helix is would solve all your problems.

John

Reply to
John

John fired this volley in news:i6qdne64- snipped-for-privacy@giganews.com:

Or dry-nitrogen flooded rigid co-ax! 'Done a few of those lines on 'real' transmission towers.

LLoyd

Reply to
Lloyd E. Sponenburgh

"Lloyd E. Sponenburgh" fired this volley in news:XnsA451D3A60C63Elloydspmindspringcom@216.168.4.170:

I should have also said "helium-filled", but that gets into another realm!

Lloyd

Reply to
Lloyd E. Sponenburgh

I have a hundred feet of that in storage left over from a cell repeater job. I don't think Gunner could even afford the connectors, let alone the cable.

Reply to
rangerssuck

I don't have spare. I need to buy more at the next hamfest.

But for marine use -- some caveats.

1) Best to use crimp connectors, not solder.

2) Heat-shrink sleeving over the crimped ferrule.

2) *especially* -- look for self-sealing tape to wrap where the wire enters the connector, and over the whole area where the connector goes into the antenna at that end of things. this is important enough on an antenna on a tower where it gets rained on, but our where salt water is involved -- even mores so.

Good Luck DoN.

Reply to
DoN. Nichols
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Arrrggghhh! The PL-259 is the worst connector for weather conditions of any in common use. Especially the one at the top of the mast. At least the solder versions of PL-259 tend to wick up water where the shield is soldered to the outer body. Crime is a bit better, but the seal where it screws onto the other connector is not watertight. A BNC or a Type-N have a resilient rubber seal inside the connector to keep water out of the mated pair.

You can probably get away with the PL-259 inside the cabin out of the weather, but the other connectors are better there, too.

Good Luck, DoN.

Reply to
DoN. Nichols

Do they make whips for console radios? You don't really need the height for local chat. 1' and 3' whips run from $15 on up.

Will these work?

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Reply to
Larry Jaques

That's one more reason to avoid an antenna on the mast, isn't it? I'm surprised you don't have a portable instead.

Reply to
Larry Jaques

I can't imagine what you want a wind speed transmitter for, but a simple wind vane type of wind direction gizmo is a good addition.

But I think that you are building in a lot of complexities. You can easily put a wind vane on the mast head as well as a whip antenna. Run the antenna feed down the inside of the mast and out through a grommeted hole 6 - 12 inches from the bottom. Terminate the feed with a coax connector. Run the feed from your radio through the deck close to the mast fitting on the cabin top through a compression gland and terminate in the other end of the connection.

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Take it apart to lower the mast.

I used foam core RG-8 on my last boat that lasted for 15 years with no noticeable loss in power.

Re single handing. Certainly run the sheets back to the cockpit but I found that trying to run every line back to the cockpit wasn't all it was cracked up to be. Routing the halyards through several blocks and changing direction a couple of times means that they get hard to pull and you might need a winch to tension the main. If the idea is to douse the sails quickly in a sudden storm then you will need downhauls on the sails as in a big wind they can't be depended on to come down and stay down by themselves.

Reply to
John B. Slocomb

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