UHF Antenna (Larger Scale)

[Skibble5150]

Hello all,

I've sucessfully built several of those coat hanger antennas.
You know the ones that have 8 'V' segments (see link:)

http://blog.makezine.com/archive/2009/01/maker_workshop_dtv_antenna_steadyca.html

The Vs are 7" long and gapped 3" at the tip.
I even made one out of 1/8" solid aluminum and 1/8" hollow copper tubing.

All work great and comparable to the store bought one I use as a benchmark.

I'd like to go larger scale with this if it would make a difference.

Does anybody have the math involved to (for example) make the Vs much larger?
Will this aid in reception? I saw plans for one with 10" V's but nothing larger.

I am thinking of Vs up to 14" in length. Should it just simply be rescaled?
Like, if the Vs are 14" instead of 7", and the gap at the tips was 3", should it now be 6"?

What about the distance between the Vs? And the gap between the 2 vertical sections that join all of them?

If anyone has an idea on improving this great little design, please let me know.

Any other plan would also help me out. I love this OTA HD stuff and this great site/forum!

Greg
Montreal, Canada

[teleview]

Making the bow tie metal elements longer will lower the operating frequency of the antenna , the antenna can become very large in a hurry. Here is one web site that has a flexible operating design program for sale. http://www.antennamagus.com . I will post more information on calculating antenna element lengths.

[teleview]

Do not increase the 3 inch gap. As this will create undesirable impedence changes. The gap between the antenna elements is about 300 Ohm with a 2 to 3 inch gap. Here is some information on antenna element wave lengths. http://www.kyes.com/antenna/rabbitear.html

[teleview]

Here is some inflammation on antenna stacking. . http://www.hdtvprimer.com/ANTENNAS/16bay.html . . http://www.hdtvprimer.com/ANTENNAS/32bay.html

[Dave Loudin]

The best information concerning bowtie arrays for Hi-VHF and UHF is at http://m4antenna.eastmasonvilleweather.com/index.html . A great deal of modelling and testing went into what you'll find there. For additional help with reception in the Montreal area, there's a thread within the OTA part of the forums at digitalhome.ca . Good luck!