Topband: Supporting Ladder line

Mon Jan 8 11:15:15 EST 2018

One more thing...if you are supporting ladder line with the recommended 
twist, you could actually run the paracord through the holes in the 
ladder line. I don't think it would have any impact on the performance 
of the ladder line.

73

Dave, KD9VT

It's a Belville thing and you wouldn't understand.

------ Original Message ------
From: "Vic Lindgren" <g4byg at lindgren1.karoo.co.uk>
To: "jeremy maris" <jeremy at maris.plus.com>
Cc: topband at contesting.com; "Jim Garland" <4cx250b at miamioh.edu>
Sent: 1/8/2018 9:47:52 AM
Subject: Re: Topband: Supporting Ladder line

>Thank you everyone for your contributions regarding my questions re 
>Ladder Line.
>We will try a test run of the RG6U as suggested by Jeremy. Mainly 
>because we already have a source on site of the cable he suggested.
>The WD1A telephone wire does not appear available in the UK.
>You all appear to agree that it matters not whether supported 
>vertically or horizontally,as long as a twist is made to help maintain 
>both balance and wind survival. All great info folks.
>Will let the group know our progress with the project shortly.
>73
>Vic
>G4BYG (G6M)
>
>
>>On 7 Jan 2018, at 10:28, jeremy maris <jeremy at maris.plus.com> wrote:
>>
>>Hi Vic,
>>
>>I’ve done something similar to Jim with two paralleled runs of WD1A 
>>for a bi-directional Beverage and it worked very well.
>>
>>According to the specifications, WD1A is made up of two 0.85mm 
>>diameter conductors separated by 0.85mm between the inner surface of 
>>the conductors.
>>I took the effective diameter of two paralleled strands of WD1A to be 
>>2mm. Two lines spaced apart by 50mm gives about 450 ohms impedance.
>>
>>Paralleled strands of WD1A at 450/600 ohms are OK for RX but you want 
>>to use the line for feeding QRO to a transmit antenna, so loss 
>>matters.
>>
>>I’ve considered using RG6U spaced apart by 150mm for 450 ohm TX 
>>transmission line but think that I’d need too many poles to support it 
>>with acceptable sag.
>>Aluminium wire or copperweld would be much better - it would be 
>>lighter and hold more tension so less sag, fewer supports needed and 
>>more consistent impedance.
>>
>>Re horizontal versus vertical spacing, don’t think it will make much 
>>difference on taught lines raised above head height.
>>
>>73 Jeremy G3XDK / G4AQG
>>
>>>On 6 Jan 2018, at 21:05, Vic <g4byg at lindgren1.karoo.co.uk> wrote:
>>>
>>>Thanks for that Jim,
>>>
>>>Well we plan on using some on site "Shot Gun" coax (about 8 gauge 
>>>diam) as the ladder line conductors with a 6 inch spacing. Which on a 
>>>test length gave us around the 450 ohm impedance we require.
>>>
>>>I dont know the diameter of that WD1a wire but suspect it is quite 
>>>small which would make home made 450 ohm line spacing very small 
>>>indeed.
>>>
>>>Your method of supporting using the wood clamps sounds a good idea as 
>>>we were concerned about the plastic clamps breaking due to flexing 
>>>and UV deterioration.
>>>
>>>If our conductors fail through the flexing then we may bite the 
>>>bullet and buy some Aluminium wire as Rik N6RK uses.
>>>
>>>All useful info though and thanks again Jim.
>>>
>>>73
>>>
>>>
>>>>On 06-Jan-18 20:38, Jim Garland wrote:
>>>>Vic, I've had nothing but bad luck in trying to support long 
>>>>horizontal lengths of ladder line. In my case, I have two 720 ft 
>>>>bidirectional beverages, which I initially made of heavy duty 
>>>>commercial ladder line. I supported the line with wood 4"x4" posts, 
>>>>spaced sixty feet apart, using the little plastic ladder line 
>>>>clamps, sold in the US by DX Engineering.
>>>>
>>>>After only a month or so, the plastic clamps broke apart because of 
>>>>the repetitive flexing of the ladder line in breezes. I replaced the 
>>>>clamps with wood clamps, screwed into the top of the posts. These 
>>>>survived with no problem, but the ladder didn't. After six months or 
>>>>so, I started having breaks in the line from the flexing, and after 
>>>>spending two years repeatedly repairing the line, I gave up and 
>>>>threw away all 1500 feet of the stuff.
>>>>
>>>>Finally, I settled on WD1a military surplus field telephone wire, 
>>>>available from many sources for about $50 USD in half mile lengths. 
>>>>I use two parallel lengths of the wire, threaded through twin 
>>>>ceramic insulators screwed into each 4x4 wood support (available 
>>>>from a farm supply store), with a pulley at the far end to equalize 
>>>>tension in the two lengths. In three years, it has worked perfectly, 
>>>>with no problems at all.
>>>>
>>>>I'm not disparaging ladder line (or the plastic clamps) at all. The 
>>>>commercial stuff just isn't designed for long horizontal lengths.
>>>>
>>>>73,
>>>>Jim W8ZR
>>>>
>>>>>-----Original Message-----
>>>>>From: Topband [mailto:topband-bounces at contesting.com] On Behalf Of 
>>>>>Vic
>>>>>Sent: Saturday, January 06, 2018 01:17 PM
>>>>>To: topband at contesting.com
>>>>>Subject: Topband: Supporting Ladder line
>>>>>
>>>>>Has anyone idea's of how to support a long (750 ft) length of home 
>>>>>made
>>>>>450 ohm ladder line ?
>>>>>
>>>>>Is it possible to use it supported from posts in a vertical 
>>>>>orientation or will that introduce
>>>>>imbalance.
>>>>>
>>>>>I would prefer not to have it supported horizontally due to added 
>>>>>cross arms being
>>>>>required.
>>>>>
>>>>>Have scoured internet sources but their appears little information 
>>>>>available on the subject.
>>>>>
>>>>>I plan to feed a Marconi Tee Vertical (Hairpin Matching) with 9:1 
>>>>>transformers at each end
>>>>>of the ladder line enabling use of 50 ohm coax at each end for 
>>>>>convenience.
>>>>>
>>>>>73
>>>>>
>>>>>Vic
>>>>>
>>>>>G4BYG (G6M)
>>>>>
>>>>>_________________
>>>>>Topband Reflector Archives - http://www.contesting.com/_topband
>>>>
>>>
>>>_________________
>>>Topband Reflector Archives - http://www.contesting.com/_topband
>>
>>—
>>Jeremy Maris
>>
>>
>>
>>
>>
>>
>
>_________________
>Topband Reflector Archives - http://www.contesting.com/_topband

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