Hi. The gain for an 8 element collinear approaches 9 dBi by squishing the 'donut' for omnidirectionality.
Am fine with that. Now, how can I build one to work wide from 470 to 700MHz ? What has to be considered ? What type of elements determines bandwidth ?

 

Hello,

As far as I know, collinear antennas are quite narrow banded.
Perhaps you can find more info in these books:
https://archive.org/details/TheArrlAntennaBook
https://the-eye.eu/public/Books/Electronic Archive/ARRL_Basic_Antennas.pdf
https://the-eye.eu/public/Books/Electronic Archive/JonesAntennaHandbook.pdf
https://the-eye.eu/public/Books/Electronic Archive/Practical_Antenna_Handbook.pdf

Bertus

 

Hello,
I don't know why you think VHF channels are obsolete, I have two stations near me that are.

 

Thanks. Can you produce a current document confirming there is any television broadcasting going on under 470MHz as of today in USA ?
Perhaps you believe they are VHF.

As much as I know ----> https://otadtv.com/frequency/index.html To please the 5G thingy.

 

Hello,

Perhaps the wiki can tell you:
https://en.wikipedia.org/wiki/Lists_of_television_stations_in_North_America

Bertus

 

Hi Bertus. See nothing current in that wiki. ----> Edited post #4 with a link !

 

https://www.dennysantennaservice.net/vhf-tv-stations.html

Thanks. Can you produce a current document confirming there is any television broadcasting going on under 470MHz as of today in USA ?
Perhaps you believe they are VHF.

As much as I know ----> https://otadtv.com/frequency/index.html To please the 5G thingy.

https://nocable.org/availability-report/zip/97266-portland-or/

Two local stations.
VHF-Hi
180 MHz

VHF-Hi
204 MHz

A US station on RF channel 3.

3

60

60.31

61.25

63.142857

65.75

66

https://publicfiles.fcc.gov/tv-profile/wsbs-tv
RF channel 2
https://publicfiles.fcc.gov/tv-profile/wlbz

 

Thanks. Can you produce a current document confirming there is any television broadcasting going on under 470MHz as of today in USA ?
Perhaps you believe they are VHF.

As much as I know ----> https://otadtv.com/frequency/index.html To please the 5G thingy.

https://www.google.com/search?clien...VD2qwKHWwPDn4Q6RMwF3oECBkQBA&biw=1600&bih=758
https://www.google.com/search?client=firefox-b-1-d&q=will+tv