Coax for VHF

[SoonerSailor]

Thanks for the info provided, Eric. I've always soldered myself, but I am tempted to get the tool and try crimping. It does seem that crimping could provide more consistent results. Which tool and connectors do you favor? And which silicone tape do you like to use to seal with? I've used a 3M product that seems to do the job (and CoaxSeal too), but I'm not sure its a silicone tape.

Chip

[fairbank56]

As a professional, the tools I use are mostly Amphenol products and are quite expensive however there is a crimp kit available from www.mouser.com that is good quality and includes many die sets. You can go to their webpage and type in 382-0330 in the search box. It runs about $80. I also purchase Amphenol connectors from them and www.rfparts.com line of connectors. The tape is called coaxwrap and is also available from rfparts. It is sold under various names such as rescue tape and Iv'e even been seeing one of those info-mercials on tv but can't remember what they are calling it. something like fix-it-all maybe. I believe West Marine also sells it. A good pair of small pointy scissors makes accurately trimming the braid easy. I use Proskit SR-330.

Eric

[btrayfors]

One point which I believe has not been covered in this thread has to do with the prevention of inadvertent shorts due to cable movement within the PL-259 connector. This is particularly important with the smaller diameter cable (since with RG-213, RG-214, RG-8, etc. the black insulation is actually screwed into the body of the PL-259 and is thus held firmly).

If you fail to immobilize the coax with respect to the connector, it can move and possibly cause shorts. That's why I always solder the braid thru all four holes AND cover the coax and half the PL-259 barrel with heavy adhesive-lined heat shrink tubing. This way, it's both "waterproof" and extremely unlikely to develop a short circuit.

BTW, I always use adhesive-lined heat shrink tubing on the larger coax as well. It makes an attractive, robust, and "waterproof" connection.

Bill

[fairbank56]

That's another advantage of crimp connectors. Since the shield goes over top of the connector, not inside of it along with the center conductor, and is sandwiched between the connector body and the crimp ferrule, shorts are all but impossible unless you allow a strand/s of the braid to go up into the center where it doesn't belong during installation.

Chip,

Just remembered. I buy a lot of stuff from MCMElectronics and I noticed recently that they now have a dirt cheap crimping tool although I don't know the quality of it. The dies of these types of tools are often interchangable between brands.

Eric

[CarinaPDX]

I really hate to get back to the terminal thing, but I think it is worth reminding those who insist on using RG-58 or RG-8X that an adapter is required for a standard PL-259. Without one the connector just flops around on the end of the coax <shudder>

Also, as far as trimming the braid goes, nothing has worked as well for me as a pair of nail cutters (nail as on fingers and toes). It is easy to get a nice straight cut.

Greg

[Boracay]

First, thanks to all posters who have made a difficult subject that much more understandable.

I have an old, thin coax (type unknown) running from the top of my mast to a new base model SH VHF. Of course the PO terminated the coax just after it comes through the deck so I racked off to my local electronics store where a rather grumpy salesperson sold me the worst looking flimsy connector that I have ever seen. Two thin bits of metal folded over the coax and the centre cable was screwed into place.

Holding it above my head in a confined space I did possibly the worst job ever of joining two bits of metal.

When the Chief Radio Officer did a radio test (Ch 22!) with Marine Rescue, Sydney recently we got a faintish response asking where we were.

We were in a long bay with high cliffs either side (Spit Bridge), but the response was from a station way up the coast. Marine Rescue Sydney gave us a 5/5 (best possible) when they realised where we were. They probably had to let their eardrums recover before responding.

To keep this on topic (I guess) VHF is essential safety equipment and even a poor installation is way better than none at all.

[btrayfors]

Originally Posted by Boracay

....
To keep this on topic (I guess) VHF is essential safety equipment and even a poor installation is way better than none at all.

Yeah, but you better not depend on it continuing to work, even fitfully.

The only way to "splice" coax is with proper connectors on each end (PL-259 in this case) and a UHF barrel connector.

And, since the thin coax is of unknown type...and I assume age...you might plan on replacing it with proper coax for your VHF...RG-213 or, better, RG-214 or even LM-400. If you absolutely can't fit the thicker coax, then RG-8X is probably the best bet in readily available coax.

You're right about VHF being "essential safety equipment". To my mind, that means that one should do everything possible to ensure that it is working as well as possible.

Bill

[GordMay]

Originally Posted by SoonerSailor

... And which silicone tape do you like to use to seal with? I've used a 3M product that seems to do the job (and CoaxSeal too), but I'm not sure its a silicone tape.
Chip

Scotch 70
Self-Fusing Silicone Rubber Electrical Tape

[Boracay]

Regrettably the coax cable leads to the top of my mast which is way beyond my reach.

When the mast needs some serious maintenance I'm planning on replacing the aerial and the coax.

Until then it seems to work just fine...

[Mambo]

Okay, here's one:

85' VHF coaxial run. Would you use

RG-213 with a junction (barrell connector)

or

RG-8X with no breaks in the line?

Thanks for your opinions.

[btrayfors]

Originally Posted by Mambo

Okay, here's one:

85' VHF coaxial run. Would you use

RG-213 with a junction (barrell connector)

or

RG-8X with no breaks in the line?

Thanks for your opinions.

RG-213 with a barrel connector. Every time!

BTW, the barrel connector is a red herring; recent tests have shown that the insertion loss is MUCH less than generally supposed and, effectively, is negligible.

I'd also consider RG-214 in lieu of RG-213. It's got double-braid shielding. I've come to like it and use it a lot.

Just be sure the terminations are done correctly and everything is clean and TIGHT. Tape the connection well and it will last many years without deterioration.

Bill
WA6CCA

[careka]

RG-214 is standard for offshore platforms in my part off the world.(north sea)
Very good. but you must also have a good antenna, dont forget that.
The RG-214 is very stiff, but i used it on a Benetau Oceanis 411 clipper.
and all in one pice.
And will get it on our new boat also.

[btrayfors]

Originally Posted by careka

RG-214 is standard for offshore platforms in my part off the world.(north sea)
Very good. but you must also have a good antenna, dont forget that.
The RG-214 is very stiff, but i used it on a Benetau Oceanis 411 clipper.
and all in one pice.
And will get it on our new boat also.

I've found that Belden 8268 is somewhat more flexible, and has identical specs to RG-214. Came across several hundred feet of it a couple of years back at a good price, and grew to love it. Unfortunately, it's all gone now...on customer boats!

Only problem is the diameter of the double-braid shielding is a bit more than will easily pass thru the hole on many PL-259 connectors. After carefully drilling out the hole, I got smart(er) and now remove one of the braid layers before inserting into the connector! Duh!

Bill