# Toroidal Wavefronter antenna



## blink

Has anyone every thought about a scaled up version of the 
Toroidal Wavefrontier antenna.
More than a 55cm or 90cm antenna.
A 120cm, 180cm or 240cm antenna


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## FTA Michael

I see references to such large-scale torodial antennae, but for most situations, a motor is the more typical way to receive Ku-band signals from Ku-band satellites.


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## blink

what i em looking to see happen is a bigger antenna than for ku band only, 
but for c band as well.


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## FTA Michael

I've never seen a toroidal C-band dish, which doesn't mean they don't exist somewhere. Is there some reason you would want to avoid a motorized dish?


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## kenglish

Take a look at this one, which is on "my" roof:

http://www.atci.com/images/Simulsat Project Photos/UT, Salt Lake City SS5 C-Ku.JPG

Be aware, it took two cranes (a 100-foot one that helped assemble the 300-foot one) to put it together and lift it.


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## Richard King

"Your" roof is a thing of beauty.


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## blink

small space in yard, Do not want antenna farm, check tele satellite, c band 
has been made to work with a 1.2 meter dish, also because then i can 
combine c and ku band on the same feed


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## FTA Michael

Those are all good reasons why you'd want to restrict yourself to one dish. But I still don't know why you don't want a motorized dish.


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## blink

is possible to get a atsc digital tv transmitter to be put on after a terrestrial antenna.
But for a private home system. i want to multicast a number fta satellite channels .


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## FTA Michael

I found one. Go here (http://www.dvb101.net/comersus/store/satellite_dishes.asp) and scroll down to "Wave Frontier Toroidal T90". It's listed at $279, it's not much prettier than two or more individual dishes, and it'll take some tweaking to get right, but there you go.


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## blink

Were do i fine the design math for the toroidal antenna.


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## FTA Michael

There's a book called Small Antenna Design, reviewed here: http://www.analogzone.com/book0807.htm, but that doesn't look like what you really want.

The standard dish uses a parabola to bounce the signals to a single point. I would guess that the toroidal dish uses its shape to bounce the signals to a short line, where the focal position along the line depends on the angle of the incoming signal. Maybe someone with more experience with these things can chime in.


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## TonyM

FTA Michael said:


> The standard dish uses a parabola to bounce the signals to a single point. I would guess that the toroidal dish uses its shape to bounce the signals to a short line, where the focal position along the line depends on the angle of the incoming signal. Maybe someone with more experience with these things can chime in.


The Toroidal dishes have dual reflectors so the signal comes down, bounces off the mian dish at an angle, hits the 2nd reflector and goes to the LNB. It doesnt focus on one point like a normal fixed dish. It focuses on the LNB line and not a specific point. That's how you can have (in my case) 13 LNB's with very little loss on signal compared to a motorized.

Advantage is you can have multiple LNB's but the bad part is in most cases it is a pain in the rear to align for the first time and shouldn't be doen by a newbie. A couple other drawbacks are you are limited to 40 degrees (but I have more) and 2 degree separation is not really able to be done normally.

It does take very precise aiming to get the ends of the bar to work. Setting this up does take a good weekend or more depending on how many LNB's you want. But right now I have 72,74,79,83,85,89,91,97,101,103,107,111,119 on mine. They say you cant get 2 degree spacing mainly due to the holder for the LNB's being too big but it is possible (on the ends of the bar its easier). 72 is bend almost behind 74 but I do get the stuff on there like GBN and feeds pretty good (they are lower than the mototrized but stable enough to work)

89 & 91 was much harder because they were in the middle but a little twisting of the LNB holder and both sats are better than the motorized.

101/103 is the worst of the bunch mainly due to 103 being just weaker and a screwy skew. 101 I can get KUIL, 3ABN and Hope Net really good but LLBN and RTPI are either weak or non existant

107 & 111 is for my StarChoice subscription

119 is there right now for the audio. I had to add an extension to the bar to get it to work. The only reason it works is due to being higher powered. KU won't even blip on it (tried 121)

I tried to get 89/91/93 but that wont work in the middle. I can get 95/97 but 95 is really weak (30-35 on the Pansat) so I kept it as is. I know the farther away from the middle the better the odds are of 2 degrees. At one point I did have 83/85/87 instead of 89. 87 had lower signals but it worked (i had to ziptie it to another LNB to make it hold).


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## blink

How many toroidal Wavefronter 90cm antennas would it take to receive all the 
ku-band satellites over the usa.


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## TonyM

depends on location but seeing you're in the vicinity of me (MN) Id have to honstly say 3

Unless you need like PAS9 (58W) I would do something like this. KU is on the following
72,74,79,83,85,87,89,91,93,95,97,99,101,103,113,116.8,123,127,129

105,107.3,111.1,121 are subscription services so unless you have those, they really don't count. 99 & 127 doesn't have anything on it either. Another issue is from 103 to 123 there is only 2 satellites that have stuff on them so there is kinda a wasteland

So one dish could do 72,74,79,83,85,89,93,97,101,113 and the other could do 87,91,95,99,103,116.8,123,129. That would cover all the active satellites.

I use one with 72,74,79,83,85,91,93,97,101,103,107.3,110,119. 107.3, 110 & 119 are for subscriptuion services. 2nd 36" dish for 123 & 129. SO I'm missing 87 (which I am working on wedging it in between 85 & 91), 89 (not much on there but ABCNewsNow), 95 (CCTV). 113 & 116.8 are useless to me as I know speak Chinese or Spanish


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## blink

has a bigger toroidal antenna ever been made.


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## HDTVFanAtic

blink said:


> How many toroidal Wavefronter 90cm antennas would it take to receive all the
> ku-band satellites over the usa.


I have done it for 18 months with 2

61-101W

101W - 148W

At some point in time I will probably move the first from 61W to 71W - 111W to handle the 107/110/111 issue and just use a single dish pointed at 61W for that.

I have a 1.2M looking at 148W which is the only way to get a signal around 80 in my part of the Country - as the T90 will only give me a high 60 on 148W - so I could move the upper one down to 139W as well.


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