Topband: Beverage strain auto-disconnects

[Bill Wichers]

Typical "fishing line" is made of nylon. Nylon will stretch far more than the steel in the WD-11A and will be of limited usefullness as an additional strength member as a result. This is a similar problem to that of fiber optic cable since the glass fiber doesn't stretch. In fiber optic cables where high strength is required aramid yarns are generally used (like kevlar) due to low stretch properties of that polymer.

If WD-11A isn't strong enough the next best option is probably just a higher-strength/heavier wire of equivalent design. The nearest substitute I'm aware of is rural "C" wire (basically telephone service drop cable). I have previously referred to that type of cable as "superman's zip cord". It is basically zip cord with two wires that are each solid copper clad steel of about 16 gauge if I remember correctly. I would estimate it has a break strength of 500+ pounds although I haven't ever tested it for tensile strength.

There is a newer type of telephone drop cable that has a single 22 gauge copper pair molded into a jacket containing glass reinforcement. The only conductive part of the cable is the copper pair (and it's solid copper wire). This might be useful to replace WD-11A as well and is probably cheaper -- and definetely is lighter weight -- than rural C wire. If anyone is curious I can look up the spec number for that wire and post it.

-Bill
[Sent using Blackberry Messaging]

----- Original Message -----
From: topband-bounces at contesting.com <topband-bounces at contesting.com>
To: Tom W8JI <w8ji at w8ji.com>; topband at contesting.com <topband at contesting.com>
Sent: Fri Jul 20 19:07:45 2012
Subject: Re: Topband: Beverage strain auto-disconnects

If the WD-11A is so weak and a repair problem why not support it on one of 
the higher strength fishing lines as a messenger?

Carl
KM1H


----- Original Message ----- 
From: "Tom W8JI" <w8ji at w8ji.com>
To: <topband at contesting.com>
Sent: Friday, July 20, 2012 12:59 PM
Subject: Re: Topband: Beverage strain auto-disconnects


>> However, single wire Beverages are out. The only way I can have
>> Beverages in more than a couple of directions (south, southwest, and
>> west) is to make them reversible. All feeds have to be on the end
>> that is on high ground so that leaves two-wire Beverages with a
>> reflection transformer at the far end.
>
> I see now.
>
>> I settled on WD1A wire for ease of installation. BUT the stuff is a
>> nightmare when it breaks! It is never a clean break, but rather a
>> badly frayed section at least several inches long. Over time the
>> Beverages quickly shorten from cutting out the bad section and
>> splicing, requiring re-adjustment of the end points and/or splicing
>> a new section in. Splicing the stuff is not fun with the steel
>> strands, and splices must be COMPLETELY waterproofed or else the
>> steel strands rust through and the wire becomes too weak. Not to
>> mention the tinned copper strands seem to get "eaten" by the rust.
>
> This is exactly the problem I have with Wireman stranded ~400 ohm ladder
> line. After a few years, if water gets inside, conductors  rust through.
>
> Heat from soldering also seems to remove the ultra thin copper layer over
> the steel core. I suspect that wire is not copper clad, but some sort of
> copper flash or plate.
>
> Anyway, I see now what you are doing.
>
>> I will admit I haven't tried "window line". I should be able to
>> install it with a level of aggravation somewhere between two
>> separate wires and the WD1A I now have. But I imagine that stuff
>> isn't the most fun to splice when it breaks either?
>
> The solid wire stuff is, IMO, much easier to splice. Stranded has the same
> problem you describe. It has to be watwerproofed, and heat removes the 
> thin
> copper "whatever" on each strand.
>
> 73 Tom
>
> _______________________________________________
> UR RST IS ... ... ..9 QSB QSB - hw? BK
>
>
> -----
> No virus found in this message.
> Checked by AVG - www.avg.com
> Version: 10.0.1424 / Virus Database: 2437/5143 - Release Date: 07/20/12
> 

_______________________________________________
UR RST IS ... ... ..9 QSB QSB - hw? BK