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Discussion Starter #1
Hi All,

The mast is coming off tomorrow for a total refurb. It's never been off the boat which is 34 years old. There is no "trap door" at the base of the mast and the wires (including coax) coming out of the dance pole below the floor are single runs... all the way to the electrical panel and the radio (which is in the aft cabin). I'm having trrouble believing the boat was built from the factory with no breaks in the wiring from the top of the mast to the back of the boat. But what if... it's so. I plan on slowly lifting the mast up to see if maybe there are breaks there at the bottom of the mast. If not, I won't have any coice but to cut everything below the floor, tie a painter line to the wires and pull them out with the mast going up.

Will splicing in a connector upon reasembly adversly affect VHF performance? Any disscussion is apreciated.

Dave
 

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a good quality connector and barrel, waterproofed will do fine. Use Amphenol or better, silver plated w/ teflon core. Your VHF will not know it is there.

IF the coax is more than 10-12 years old, it would be best to replace it with LMR, quality cable .
 

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Dave, it is very possible that the VHF coax is not original to the boat. If it is, and that's 34 years old, it is probably time to replace it. No way to tell without more information but the odds are, it needs to be replaced.

Normally you run coax through a deck or bulkhead with a bulkhead connector. That's pretty much like a "pipe nipple" in a floor or table lamp. It is a "pipe" that may be several inches long, long enough to penetrate all the way through the bulkhead or deck, and there is a female VHF connection on both sides of it. You embed the bulkhead connector in the bulkhead (or deck) and then you fit a male connector to each of the coax cables. One screws in to each side.

That's the simplest and neatest way to run it. If you simply cut the cable and then reconnect it, you actually do the same thing but you use a female-female connector hanging in free space somewhere instead of the bulkhead connector. (Coax is always terminated with a male fitting, never a female on the cable.)

There are a number of "patent" fittings these days that can be crimped or clamped onto the cable, which are better than first-time solder attempts. Just shop carefully, don't assume whatever is on the chandlery shelf is the right choice. If you've got a ham (amateur) radio store somewhere around, odds are they've got better fittings at better prices.
 

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Mermaid Hunter
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I'm having trrouble believing the boat was built from the factory with no breaks in the wiring from the top of the mast to the back of the boat.
*sigh* Don't be surprised. Boat builders do funny things.

Will splicing in a connector upon reasembly adversly affect VHF performance?
Yes. Will you notice if you do a good job? No.

Avoid the Shakespeare and similar cheap crimp on connectors. Get good quality silver-teflon connectors.

Normally you run coax through a deck or bulkhead with a bulkhead connector.
A through-bulkhead connector or a barrel connector is really two connections, each of which is a small impedance bump and reduces performance slightly. It won't kill you but if it is easy to do better you should. There are inline SO-239 connectors that result in a single connections. See UHF RG-8 RG-55 RG-58 RG-14 RG-59 RG-213 RG-214 RG-9913 PL-259 and scroll down to the SO-239 section. SO-239 is the female version of the male PL-259 connector.

Under no circumstances use a terminal strip for RF connections.
 

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As a practical matter, on a boat, I'd put a 100% watertight deal in the deck as being more important than a slight impedance bump in the coax. The bulkhead fitting in the deck ensures that, and also ensures that he can replace either side of the cable with a handy store-bought conventionally terminated cable in the future, instead of needing whatever that special fitting wants. (Can't tell from the picture or lack of description what is special about it anyway.)

Impedance bumps, important, yes. But in the bigger picture? I think "dry boat" "dry cable" and "standard replacement parts" will be more important.
 

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Discussion Starter #6
Hi guys,

Thanks for the replies. The mast came off without a hitch. There was plenty of extra slack at the base for all the wiring. But if I hadn't seen it, I wouldn't believe it - the coax was one piece. So I cut it at the base. I'm not going to create a "through deck" type of connection in this late stage of the boats life. With this mast refurb (which includes paint, news sheeves, and standing rigging and new wind sensors), I don't plan on taking the mast off again. So I will terminate the ends of the coax with the best connectors I can get, weather proof them best I can and call it good.

How would I best weather proof the connectors?

Dave
 

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Mermaid Hunter
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instead of needing whatever that special fitting wants. (Can't tell from the picture or lack of description what is special about it anyway.)
An inline SO-239 connects just like a PL-259 and just means one connection instead of two. Cutting the number of connections in half is what makes it special. It's a broadly available part.
 

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"An inline SO-239 "
Except catalog listings show every "this goes on the end of a cable instead of a flat surface" fitting under that name. There must be a slightly different name for the connector you're describing? The URL you'd given before just has a fuzzy picture that could be any SO-239.
But unless he's using RG8 or another thick cable, wouldn't he get even less of an impedance bump by using a mini-UHF connector, or other connector designed to RG58 (etc) instead of using the UHF with fittings? In for a penny, in for a pound?


Dave, whatever you connect them with, you can use "coax seal" or a similar butyl or silicone rubber self-fusing tape to seal over it. Sold in radio shops to seal antenna cables, possibly available from Radio Shack in the "adult only" section. 3M's tape in the electrical section of Home Depot, etc. for the butyl product. In the plumbing section for the silicone product, or in the "as seen on TV" section in Walgreen's. Also sold in chandleries as "Rescue Tape" at a higher price, possibly the same material. If you give these 48 hours to self-fuse after application, the butyl ones pretty much become one piece. The silicone ones are easier to strip off, but supposedly just as durable. And come in colors. (G)

Whether you also use silicone di-electric grease inside, sparingly, to make sure water can't get past it, is a whole other debate. If you get any grease on the outside, of course, the sealing tape won't properly seal.
 

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Mermaid Hunter
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"An inline SO-239 "
Except catalog listings show every "this goes on the end of a cable instead of a flat surface" fitting under that name. There must be a slightly different name for the connector you're describing? The URL you'd given before just has a fuzzy picture that could be any SO-239.
The descriptions list the appropriate cable - LMR-400, RG-58, RG-8X, RG-8, ... all in the description.
 

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Well, elsewhere I'm seeing the impedance bump translates into a possible loss of 1/10th of one db, so even if that becomes 2/10th of one db for a conventional splice...I'd argue "convention" is worth that.

But you've still only referred to a piece of equipment that doesn't seem to exist. At least not by that name, no magic splicing junction thingies that I can see. Regardless of cable type. Where or what else is it called? And why are they so hard to find?
 

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Well, elsewhere I'm seeing the impedance bump translates into a possible loss of 1/10th of one db, so even if that becomes 2/10th of one db for a conventional splice...I'd argue "convention" is worth that.

But you've still only referred to a piece of equipment that doesn't seem to exist. At least not by that name, no magic splicing junction thingies that I can see. Regardless of cable type. Where or what else is it called? And why are they so hard to find?
They exist. You can buy them at RF Connection and Tower Electronics among many other sources. It isn't a magic splice - it's a female version of the PL-259 that is attached to the end of a piece of coax just like a PL-259 is. I agree that the loss is small, but if you can spend less and get better performance why not?
 

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"it's a female version of the PL-259 "
That would be just an SO-239 without the usual bulkhead fitting. Oh, I see!

On the "Why not?" side, I had the impression that always terminating cables in PL-259s was a formal standard, as well as custom. And mounting SO-239's on fixtures, part of the same standard. Standards for a reason, i.e. so you can ALWAYS swap out a cable with another standard cable.

I see your point though. Finally!
 

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See UHF RG-8 RG-55 RG-58 RG-14 RG-59 RG-213 RG-214 RG-9913 PL-259 and scroll down to the SO-239 section. SO-239 is the female version of the male PL-259 connector.
I personaly like the koax connector with a good protection against moisture.
In your list I found one connector of that type:
PL-259 LMR600 Clamp TGN for 12 $
All these connectors come from china. They are sold in Germany for < 5$.
1 Stück UHF-Stecker für H 155 / Aircell 5 / RG 58 Koaxkabel 50 ? (H1010) | eBay
The H155 cable comes in 2 qualities.
One is UV protected. When not, you get moisture into the cable.
I worked some years in the cable industry.
Moisture is the no.1 point, its the killing point.
Greetings, Wilhelm
 

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Moisture is the no.1 point, its the killing point.
Agreed. I generally avoid crimps, preferring solder. I also shy away from the little rubber sleeves that come with many connectors. I prefer layering adhesive-lined shrink wrap that helps keep water out and provides some structural support for the cable.

Remember service loops and strain relief.
 

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I generally avoid soldered connectors, especially PL-259's, and prefer crimped connectors for the same reasons. I put 3 concentric layers of heatshrink primarily for the added strength at the connector base, then weatherseal the whole connection. It makes a very durable connection that will last.

I don't trust any "weather resistant" connectors and have seen many failures even when attached on the bottom of an exposed device, out of direct weather.
 

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I generally avoid soldered connectors, especially PL-259's, and prefer crimped connectors for the same reasons.
I certainly use adhesive-lined shrink crimps exclusively for electrical connections. For PL-259s I have never found a decent crimp product. The Shakespeare units in particular are quite horrible. MaineSail has had good luck with one unit (see his Compass Marine website on pbase.com) that I have yet to try.
 

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I certainly use adhesive-lined shrink crimps exclusively for electrical connections. For PL-259s I have never found a decent crimp product. The Shakespeare units in particular are quite horrible. MaineSail has had good luck with one unit (see his Compass Marine website on pbase.com) that I have yet to try.
Amphenol, Amphenol-Connex, Times etc. all make a decent crimp/solder (crimp shield/solder pin) product. The Pan-Pacific brand I sometimes buy at my local HAM shop is made in the same factory as the Amphenol-Connex version and is pretty much identical. Amphenol-Connex #182102..

Mostly I use the Amphenol 83-1SP solder/solder but they are a tad harder to use for novices. Unless I can terminate a cable in my shop, with no wind, controlled parameters etc. I use the crimp/solder PL-259's. I probably have well over 200 crimp/solders in service and have yet to have a single one fail.. Surprisingly it was my ham buddies who turned me onto them. You do however need the proper tools...

Most of the "pre-made" VHF cables you buy from Shakespere etc. are all crimp or crimp / solder...

The big problem I have with solder/solder is that 99.5% of the ones I come across were done INCORRECTLY. To solder these CORRECTLY the shield gets 100% pre-tinned BEFORE it is inserted into the PL-259.... I see this about .5% of the time....:mad:

Improper soldering is the #1 VHF failure mode I see....

The Shakespere "pinch-on's" have an EXTREMELY high failure rate but luckily most boaters are not STUPID enough to use them.........
 

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Discussion Starter #19
As far as the "wrap" is concerned. I see alot of you using sticky versions of wrap as opposed to heat shrink. Why? Ease of use? Accessability?
 

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As far as the "wrap" is concerned. I see alot of you using sticky versions of wrap as opposed to heat shrink. Why? Ease of use? Accessability?

Two different applications. An amalgamating tape over the entire external connection once the two are mated. The adhesive lined heat shrink (dual wall) is used at the intersection between the PL-259 and the cable.
 
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