I now use 1/2 in PVC tubing which I cut in 4 inch segment, with a hole
drilled 1/2 inch from each side, providing 3 inch spacing. I use cable ties
to keep the spacers from moving up and down. A bit of work to cut and drill
the spacers, but works fine, and are a bit lighter than the ceramic dog-bone
insulators.
Dave
-----Original Message-----
From: TenTec [mailto:tentec-bounces@contesting.com] On Behalf Of Phil
Sussman
Sent: Wednesday, October 21, 2015 10:43 AM
To: Discussion of Ten-Tec Equipment
Cc: Rick - DJ0IP / NJ0IP
Subject: Re: [TenTec] Open Wire Line - D-i-Y "Professionally"
Rick,
Years ago there was a company in the USA that also sold a similar spreader.
I noticed in your web site the spreaders have three tines (forks). The old
units here were constructed out of some black material and had four forks. I
tried them out and they did work without adjusting tuner in rain, snow, etc.
Unfortunately, we are in an area of high wind and freezing cold rain. The
problem was these units would fail (tines broke off) in -20 degF weather
with any wind at all. Company went out of business.
Now I use 4" ceramic spacers on my ladder line. They look like 'dog bones'
and were sold years ago by Radio Shack, before they switched to polyvinyl.
The added benefit of the weight of the ceramic spacers keeps the line from
"whipping around" in the usually high winds in this area.
Regards,
de Phil - N8PS
Quoting Rick - DJ0IP / NJ0IP <Rick@DJ0IP.de>:
> I changed the subject line. The thread no longer pertains to OCFD,
> just Openwire.
>
> This is a response to Robs excellent post (below).
>
>
> THIS IS HOW I EASILY MAKE PROFESSIONAL QUALITY LADDER-LINE.
> If interested, read on - if not then exit and delete now.
>
>
> Rather than try to describe it in words, I have created a page on my
> web site showing how I have been doing this for many years.
>
> No offense guys, but IMO, this system makes the other stuff look
> Mickey Mouse.
>
> It's not cheap, but it's not expensive, and it is certainly outstanding.
> When you have built your own openwire ladder-line, you'll have a
> professional product for life.
> The problem for most of you is, it is only available in Germany.
>
> This is not really a problem, we live in a global economy.
>
> The main reseller of these components is DX-Wire, my biggest
> competitor. :-( Yet I buy this stuff from him and send him customers who
need it.
>
> The owner of DX-Wire and the guys here at Spiderbeam are all in the
> same contest club, The Bavarian Contest Club. We've been friends for
> twice as long as either of the companies have existed.
>
> If anyone is interested and needs assistance with ordering this, I am
> happy to help.
> If enough interest for a bulk order, as long as we have a bit of time,
> I can get this shipped to the states (Tennessee) for free (legally).
> I believe there is a 6% import tax, but I am not sure.
>
> I don't really have a chapter on my web pertaining to Openwire, so for
> now I have uploaded the page to my "CATCH-ALL" section, called
"Ricki-Leaks" ...
>
> See: http://www.dj0ip.de/ricki-leaks/d-i-y-ladder-line/
>
> 73 - Rick, DJ0IP
> (Nr. Frankfurt am Main)
>
>
> -----Original Message-----
> From: TenTec [mailto:tentec-bounces@contesting.com] On Behalf Of Rob
> Atkinson
> Sent: Tuesday, October 20, 2015 10:38 PM
> To: tentec@contesting.com
> Subject: Re: [TenTec] Open Wire Line - A CASE FOR OCFD
>
> It's important to understand that any antenna is better than no
> antenna and I'm speaking of incremental improvements in terms of an
> antenna _system_, i.e. the matching network, feedline and antenna, and
> the most transfer of power from the RF final to the load for a single
> system. There is rarely a complete utter night and day difference,
> between two somewhat similar systems, but an improvement will be
> observable over time although it might be subtle. But a dramatic
> improvement, such as going from a low dipole in town to one up 120
> feet in the country will be instantly clear. In the case of open wire
> line etc. it is more a matter of having a solid signal with one
> antenna over several bands. With any antenna the best test is seeing how
well you can do with fairly low power, almost QRP on CW for
> example. If you run enough power, a coat hanger will work, but if
> you are frequently solid copy with the amplifier off, then you are
> moving in the right direction.
>
>> I'd love to hear more about the practicalities of routing open wire
>> line from feedpoint through heavily wooded lots, through house walls,
>> etc etc, to the shack.
>
>
> There's a rich body of literature on spacing insulators that has been
> published over the years but most hams now seem to settle on either
> the ceramic spacers that can be found at hamfests, or the black
> irrigation pvc pipe that's about 1 inch diameter and can be cut and
> notched to make spacers. The pipe has the advantage of being
> lightweight, but it can get spiders and bugs in it. It seems to be UV
> resistant and although black, not a known carbon conductivity problem.
> The ceramic spacers were made in a variety of lengths--you use the
> holes on each end to hold the tie wrap wire; the feedline wire goes on
> the ends of the spacers, not through the holes. They can add a lot
> of weight to the line, but over land that is okay--I'd probably go
> with a light weight spacer from ground up to a free hanging feedpoint.
> Most people think they need to have a spacer every two feet or so
> but if the line is 3 or 4 or 5 inches apart, then once it is strung
> up, and has some tension on it, the spacers can be every 3 or 4 feet,
> allowing more length for the number of spacers.
>
> If you construct your own line you get to choose what wire you want to
use.
> I'd consider AWG 12 stranded as it is a good compromise between power
> handling and size although I think you'd have to space it pretty
> far apart to get 600 ohms impedance. The top spacer at the feedpoint
> should be strapped to the center insulator of the dipole so that it is
> perpendicular to the center insulator and directly below it, so as to
> make a X when viewed from above. then the feedline wires can be
> curved around and attached to the dipole ends so there is strain
> relief allowing the feedline to move around in the wind and not fatigue
the connection points.
>
> Supports over ground can be poles --the only thing that is important
> is that they hold the line with insulators in the weather and maintain
> the line geometry with a bit of sag but not too much, and get the line
> high enough so you can get under it and/or mow under it. I have used
> PVC pipe topped with T sections with light weight line.
>
> The feed throughs depend on the wall. If you have a window with a
> small pane, you can knock that out and put in a plexiglass pane
> drilled for a pair of banana jacks or porcelain feed throughs, or you
> can drill holes for porcelain feed throughs, -- some guys use a pair
> of RG213 stubs through the wall. If the wall is stone or brick, it's
> harder. I'd probably route to a window I could modify in that case.
>
> 73
>
> Rob
> K5UJ
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