Okay, well if you're really confused it's worth the time to straighten it
out.
No such thing as "Telerex," that I know of.
Telrex -- with an R in the middle -- is the old, high-end, antenna company.
It was "The Best" in the 50s and 60s, and I suppose into the 70s. Telrex
antennas were too expensive for most of us. They said 90% of their sales
were to commercial, government, and military, and 10% to hams. I've heard
other ham manufacturers say similar things. In any case, they seemed to
make no attempt to price their produce "for the masses." Telrex was out of
Asbury Park, New Jersey I think it was. That's where they had their machine
shop for "taper swaging" and all sorts of things they did on their
made-to-order antennas. I don't know that they kept much, if any, inventory
in stock, or that any ham dealers carried their products. They may only
sold direct -- all part of their "not for the masses" approach. Telrex also
made the "Big Bertha," which was basically the millionaire's antenna
support -- a self supporting tubular steel monopole that rotated from ground
level -- typically 112' above ground, with a pair of big monobanders on each
band, 20, 15, and 10 and a single 40M yagi. People often put VHF and UHF
antennas at the top too. In those days not nearly as many people had
"stacks" as they do now, and even fewer had "rotating stacks." The Bertha
was the "big gun's" antenna support. Some, like W3TX and WX0B, are making
rotating monopoles now and calling them "Big Berthas," but I've heard some
purists say, "It isn't a Big Bertha unless it's Telrex." Other than that,
some of the new generation of these poles are a lot taller, 150' high or
more, taking them well beyond the earlier Telrex versions. And, now guys
are putting up rotating towers, which to many is the deluxe system of today.
With them you can easily go to 200' or more, theoretically, though most hams
stay at 200' or less, to avoid FAA lighting requirements -- and the "point
of diminishing returns."
Telex -- no R in the middle -- was a headphone company -- and maybe other
things, other audio devices. Out of Minneapolis I think. Weren't they
bought by 3M? Anyway, then Telex bought Hy-Gain, creating "Hy-Gain-Telex,"
or maybe it was Hy-Gain that bought Telex -- and now I guess that
combination was bought by MFJ, right? Hy-Gain has been the maker of their
line of ham yagis -- the Long John and other monobanders, but most of what
they've sold may be their tribanders, the TH-3, TH-6, TH-7, TH-11 and
probably there were/are others.
I have a lot of Telrex antennas, and a Big Bertha (not up -- I'm WAY behind
in my installation plans). Telrex antennas do have "issues," particularly
mechanical. But, I agree with the commenter who said his has been up since
'78 with no problems, works great. The main "challenge" with having Telrex
antennas is also their "strength." They're "built like a tank," which means
you need a huskier tower to hold them on and a huskier rotator to turn them.
They're heavier, and I suppose more windload too, compared to ones by other
manufacturers of comparable performance. People will look at a big Telrex
beam and think it's a 15M or 10M beam because of the very little element
sag, compared to some others. Etc.
The main failure points, according to my observation, on Telrex antennas is
the "through-the-boom" element mounting. Telrex drilled holes through the
boom, the size of the middle portion of the element, and slipped the element
through the hole. It eliminates boom-to-element plates. It makes a neat,
tidy, appearance. The problems: When you try to take one of these apart,
take it down and take it apart, it's often very difficult to get that tubing
out of the boom, which you want to do to transport it to a new location.
Worse, over time, with the wind working on the elements and boom 24/7, a
slight amount of "play" can develop between the element and boom. Once that
first bit of "play" starts, the element starts to really work on that hole
and ream it out. Eventually, you will notice, when you look up at your
beam, that one of the elements is "floppy," moving around instead of staying
still. Let it go that way and the boom will split at that point and that
end of the antenna will fall to the ground -- bending other antennas below
it on the way. This had happened to a Big Bertha I took down in Leesburg,
Virginia (Arthur Godfrey's and "Prince Talal's" old place) -- a boom end or
two, with elements, had "shed," bending some elements on antennas below,
etc.
The worst ones are the 40M yagis, in my observation. I had a pair of
2-element 40M Telrex yagis on a 160' tower. They hadn't been up more than a
year and both looked in perfect condition when put up. While I had acquired
both of them used, they hadn't been up for most of their "lifetimes." But,
each "failed," shed an element along with the tip of the boom, within a week
of each other. Maybe it was an amazing coincidence -- I think probably
so -- and maybe it was freak winds. Those were 60-foot elements and unlike
their elements on 20/15/10, their 40M elements tapered to solid aluminum rod
for their tips -- anyway, a lot of movement in the wind and a lot of that
stress goes to where the element reaches the boom.
While I've never, myself, had an intact 3-element 40M yagi, most of the ones
I've personally seen that have been up a while have had elements fall off.
K3ZO's 3-el is an exception. It's up and intact. Consequently, I have "the
remains of" two 3-element 40s and the remains of a fourth promised to me if
I ever go get it.
The main differences between the 40M Telrexes and the ones for 20/15/10 are
the dramatic element taper (like more modern designs) that reduces weight
and windload -- and the second thing is the hairpin matches on elements,
that made it tricky, at least for me and a buddy, to make adjustments to
resonant frequency. Well, I take it back, some of my older Telrex antennas,
3-el ones, have hairpins too, on each element. The bigger ones don't. All
the 40s do.
Anyway, the 40s do seem to be more mechanically vulnerable, and they're
trickier electrically too.
Electrically.... Telrex antennas were designed empirically by the "cut and
try" method on Telrex's antenna range. They're effective. But, the modern
generation of computer-assisted design antennas are almost certainly better
electrically -- better performance. Most Telrex antennas (their tribanders
were an exception, having separate reflectors) -- so let's say Telrex
monobanders -- had evenly-spaced elements. I don't think any modern
generation antennas do this, because it's been found that better performance
can be obtained with spacings that are not all the same.
And, the well-known 8-element 15M Telrex, for instance, would work just as
well if it was only 6 elements, on the same boom length, apparently. The
6-element 20 would be just as good, better according to some people, if it
was just 5 elements. In fact, Telrex had two designs, a 5 and a 6, on the
same boom length. Some people say the 5 was better. Telrex made a
10-element 10, but some people have designs, modern designs, that are just 7
elements, on roughly that same boom length.
So, Telrex may have had more elements than needed, for a given performance
level, which added to weight and windload. Still, no doubt it's cool to be
able to say you're using a 10-element monobander, when you're on 10. There
are still some guys around who have a stack of two of those, maybe more.
73 - Rich, KE3Q
----- Original Message -----
From: "Bill Aycock" <baycock@direcway.com>
To: "Joe Barnes" <n4jbk@bellsouth.net>; <TowerTalk@contesting.com>
Sent: Wednesday, March 02, 2005 3:39 PM
Subject: [TowerTalk] Telex,Telrex,Telerex- etc ?
>
> I'm REALLY confused- The three names above, and maybe more similar ones-
> Who made what and when and how well?
> Bill
>
> At 03:09 PM 3/2/2005 -0500, Joe Barnes wrote:
>
> >Not real sure where tvd got that the Telrex monobanders were not well
> >built, Im currently using a 6 element 20 meter Telerex that wa
> >originally installed in 1978 and it still rocks, Im thinkin there are
> >few other manufactureres that can make this claim.
> >73, Joe N4JBK
> >__________
>
> Bill Aycock - W4BSG
> Woodville, Alabama
>
>
> _______________________________________________
>
> See: http://www.mscomputer.com for "Self Supporting Towers", "Wireless
> Weather Stations", and lot's more. Call Toll Free, 1-800-333-9041 with
> any questions and ask for Sherman, W2FLA.
>
> _______________________________________________
> TowerTalk mailing list
> TowerTalk@contesting.com
> http://lists.contesting.com/mailman/listinfo/towertalk
>
_______________________________________________
See: http://www.mscomputer.com for "Self Supporting Towers", "Wireless Weather
Stations", and lot's more. Call Toll Free, 1-800-333-9041 with any questions
and ask for Sherman, W2FLA.
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