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What is this antenna structure? (vertical bow tie)

by berkeman
Tags: antenna, structure, vertical
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berkeman
#1
Jun16-14, 11:25 AM
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I saw this antenna on a residential rooftop yesterday (in the US). I'm guessing it is a over-the-air Digital TV antenna, but I don't recognize the vertical bow tie structure. The antenna is about half a meter tall. Any ideas?
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dlgoff
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Jun16-14, 11:30 AM
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Very odd. I'd would just have to go and ask the residents of the home.
berkeman
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Jun16-14, 11:33 AM
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Quote Quote by dlgoff View Post
Very odd. I'd would just have to go and ask the residents of the home.
LOL. I was wearing my EMT uniform at the time (about 7AM on a Sunday morning). Probably would have scared the poor residents if I'd have knocked at the door!

Baluncore
#4
Jun16-14, 12:21 PM
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What is this antenna structure? (vertical bow tie)

Looks like a ClearStream 4 Antenna for Free Over-The-Air Digital and HD Programming.
It is operated with the reflector screen. The horizontal dipole is something extra.
berkeman
#5
Jun16-14, 12:24 PM
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Quote Quote by Baluncore View Post
Looks like a ClearStream 4 Antenna for Free Over-The-Air Digital and HD Programming.
It is operated with the reflector screen. The horizontal dipole is something extra.
Thanks! At least it looks like half of the ClearStream 4...

https://all-cryptothrift1.netdna-ssl...72-300x200.jpg
berkeman
#6
Jun16-14, 12:28 PM
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Looks to be the ClearStream 2V:

http://nsz-gs7.com/wp-content/upload...-0-345x345.jpg


Any idea what the bow tie structure does that horizontal elements don't do? Wider band?
jtbell
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Jun16-14, 12:44 PM
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I think the makers claim better performance in the VHF band than a traditional bowtie-plus-reflector design such as the DB2, enough to market it as a UHF+VHF combo antenna rather than as a UHF antenna that has some ability to receive VHF.

It came out a few years ago, around the time of the US analog-to-digital TV transition.
Baluncore
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Jun16-14, 01:02 PM
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A fishing lure must be designed for two quite different functions. Firstly, most importantly to be commercial, it must catch a fisherman, then secondly, and of little importance is to catch fish.

Like a fishing lure, the thing that is really important in consumer antenna design is style and looks. It is most unlikely that the antenna performs better, but to be commercial it must look new and different.

It is probably just an old style simple antenna underneath.
Don't get distracted by their marketing hype and the unusual plastic style.
berkeman
#9
Jun16-14, 03:44 PM
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Quote Quote by Baluncore View Post
A fishing lure must be designed for two quite different functions. Firstly, most importantly to be commercial, it must catch a fisherman
Well it sure worked on me!
dlgoff
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Jun16-14, 04:34 PM
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Quote Quote by jtbell View Post
I think the makers claim better performance in the VHF band than a traditional bowtie-plus-reflector design such as the DB2, enough to market it as a UHF+VHF combo antenna rather than as a UHF antenna that has some ability to receive VHF.

It came out a few years ago, around the time of the US analog-to-digital TV transition.
Quote Quote by Baluncore View Post
A fishing lure must be designed for two quite different functions. Firstly, most importantly to be commercial, it must catch a fisherman, then secondly, and of little importance is to catch fish.

Like a fishing lure, the thing that is really important in consumer antenna design is style and looks. It is most unlikely that the antenna performs better, but to be commercial it must look new and different.

It is probably just an old style simple antenna underneath.
Don't get distracted by their marketing hype and the unusual plastic style.
I feel sorry for all the folks that trashed their old UHF-VHF "analog" antennas. I'm receiving 45 digital channels with an antenna like this.




from http://www.walmart.com
Baluncore
#11
Jun16-14, 07:01 PM
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I remember when colour TV arrived, gone was the brown cardboard box for the new antenna, the antenna came in a white box with bright red, green and blue coloured printing. Looking at the antenna, it had brightly coloured insulator blocks, no more of that UV stable black stuff. Apart from that, absolutely nothing changed.

When digital TV arrived I designed antennas optimised for each different transmit site in this corner of the state, they are manufactured locally and installed by antenna installers based on the transmit site name. The engineering can be optimised because there is no direct sale to a customer. Because I can optimise for a specific site's band, gain, beamwidth, and F/B ratio, others who buy fancy expensive antennas from a catalogue, cannot get better reception.

The internet is a sewer that flows into your office. TV is a sewer that flows into your lounge room.
Whichever way you look at it, you need a significantly better crap detector to handle the bigger pipe.
berkeman
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Jun16-14, 10:15 PM
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