Canadian TV, Computing and Home Theatre Forums banner

1 - 12 of 12 Posts

·
Registered
Joined
·
2 Posts
Discussion Starter #1
From time to time I've seen people post comments on the Lindsay zig zag antennas. I was recently cleaning out my office and came across literature for it.This is what I consider to be the holy grail of UHF antennas.

This has more detail than I thought it would have on it. I say that because this is from 1997. I feared it was just a brochure.

Anyhow, I scanned it as a pdf file to share with you.

I'm not able to tag this so feel free to tag and share.

follow the link

https://docs.google.com/viewer?a=v&pid=explorer&chrome=true&srcid=0BxjeI1khEj3-M2U1MmQ0MWUtOTQ5YS00OTJmLWFhNzctN2M5MWMzM2Q5NTAz&hl=en&authkey=CNuw1vcN
 

·
OTA Forum Moderator
Joined
·
24,867 Posts
Great find!

Thanks for that, ajnienaber! Lindsay made terrific products but after the manufacturing deal they signed with Wade it seems like they disappeared, and I don't know whether Wade carried on with the Lindsay product line as had been announced.

That giant 4SZZ configuration has quite the numbers, but boy what a tight beam... Question to modelers: is there enough info in there to model it for verifying the quoted performance, and/or is there already a NEC-style model floating around out there?
 

·
Registered
Joined
·
7,360 Posts
Question to modelers: is there enough info in there to model it for verifying the quoted performance, and/or is there already a NEC-style model floating around out there?
Only to guess at. It doesnt say what their spacings are or the reflector to element distance or wire diameters etc.

The 1SZZ is similiar to JEDs 18.3 dBi X-GH8 here : http://www.jedsoft.org/fun/antennas/dtv/xgh.html

So, based on my past experiments with modeling directors on a GH in the same way they do, an additional .2 dBi (1.5% more gain) may come from optimized directors, and the rest of the additional gain from other optimizations such as the many more reflectors (44 vs 8) the 1SZZ has. I personally dont think the directors they put on it are worth the additional time and expense, as opposed to using the metal to build another antenna to get 2.5+ dBi more in gain when stacked. They could also probably cut the number of reflectors down to 22 from 44 and only lose another .2 dBi. The 1SZZ has a lot of overkill built into it in many ways, heh. But it has an intrinsic superior sturdier mount design compared to a single channel 19 dBi yagi.

So to answer your question, yes, 19 dBi for the 1SZZ I think is verified.

That giant 4SZZ configuration has quite the numbers,
It also gives an idea of how much of a loss that 4 way combiner has. With no loss, the gain for that 4 bay should be 19 plus 6 dBi theoretical, ie 25 dBi vs the 23.5 dBi quoted.

Ive found no other images of the 1SZZ in Google images, so ajnienaber its a great find.

And JEDs X-GH8 is about a foot shorter for about the same channel range 35 - 37 or 38 - 40, 88 inches vs 103 or 100 inches for the 1SZZ.
 

·
Registered
Joined
·
7,360 Posts
I'm intrigued by the 4 linear stacked elements. I wonder if that would work with GH, Bow tie, or SH elements?
Yeah, but you need a whole mess of them to get another .5 dBi in gain. Then the build becomes very awkward, heh. And the amount of metal used would be better applied to other uses.
The best shape Ive found for a GH director is another GH element. The same goes for a bowtie. And Im pretty sure the same would apply to the SH, as it also does to the 1SZZ.

Wow! Serious antenna weight issues? 70-600 lbs
Well, high quality stainless steel is very heavy. And very hard to cut and drill (and bend, which is why I used it in the first place). Years back, I had to fabricate some custom pieces for my boat from 1" square marine SS tubing. I went thru a mess of steel cutting blades and drill bits, and I didnt even have all that many cuts to do or holes to drill. I also used Sears special steel cutting disks on a table saw, and even they didnt last long with that stuff, heh. A welding cutting torch is really the only way to deal with that stuff, except that it doesnt leave nice edges.
 

·
Banned
Joined
·
262 Posts
Strikes me as one of those ideas that, at first glance, makes you wonder why you didn't think of it yourself, then on consideration of what you actually get for all your hard work, you remember you did consider it, and rejected it, except as an intellectual exercise. Eg. Think how many directors are needed to make a good yagi, then map that knowledge onto this antenna with only two or three... At least yagi directors are easy to build dipoles or, in those European pictures around here, somewhere, bow ties.

If I understand the raison d'être of this build properly, my advice would be to skip it entirely, flip it horizontally on a boom, and lay a corrected zig zag on it. Less work, less materials, and better performance. Otherwise, you end up with a Rube Goldberg antenna, better accomplished almost any other way.
 

·
Registered
Joined
·
7,360 Posts
Its a specialized antenna, used for CATV type installations or repeater stations. Because of the price and mounting requirements, I doubt very many were sold to homeowners.
 

·
Banned
Joined
·
262 Posts
Yeah, just thought I'd give some perspective, just in case someone got it into their head that this would be a really good thing to actualize. A lot of work for not a lot of gain. But hey, if one has the gumption, I'd be the last person to stop one from doing so... Well, maybe the SECOND last... ;)
 

·
Registered
Joined
·
2 Posts
Discussion Starter #12 (Edited)
Additional info...

When I was in the field back in the day, I installed these on a few head ends in the state of Kentucky. Two singles, one double.

Lindsay used standard stock to make all their antennas and I still have a super log somewhere. (super log i.e. directors out in front) When I find it, I'll measure the boom and element diameter to give you an idea of why they weigh so much. Not made of 1" tubing.

*What I remember is that the rear set of zig zags were the only active elements. The other two in front of that were directors. The active elements formed the expected square shape to them, while the directors were smaller with the front one being diamond shaped.

Lindsay used some of the toughest fiberglass I've ever seen for boom spacing insulators and they used that same material for the standoffs to support the elements in front.

The zig zag elements were not one continuous conductor. They were individual with flattened out ends that overlapped each other and was riveted together.

The matching transformer was in an aluminum housing with a UHF N type connector on it. A short jumper to the preamp and then to the coax hard line.

These head ends are now fed by fiber optics and the towers are gone. I checked a few years ago. Missed my opportunity. Sad...
 
1 - 12 of 12 Posts
Top