15 April 2010
I just spotted your private message. Sorry I did not notice it two weeks ago.
I also noticed foxeng's reply to you concerning commercial indoor antennas. He said, "First off, DO NOT GO WITH AN INDOOR ANTENNA. It will cause you more problems than they are worth." LOL... Yes... I suspect he is right when it comes to most of the commercially available indoor antennas.
His suggestion concerning the Channel Master 4228 outdoor antenna is certainly a very good solution to your problem. In fact a few years back, I had planned on purchasing the very same antenna, an antenna rotor, a CM-7777 mast pre-amp, a new mast, a new roof top tripod, gable mounting brackets and about 100 feet of best RG6 coax cable I could find to replace my 25 year old VHF/UHF outdoor antenna.
Somewhere along the way, I stumbled across some information on building a "Do It Yourself Four Bay Bowtie Antenna" out of coat hangers. LOL... Really!!! So, I gave it a try and much to my surprise it sort of worked, even at ground level on my driveway. It was pretty big and very ugly. It might have been okay for the attic, but for the outside world, no way. It would have rusted and rotted away in the weather in short order. Like foxeng said, "It will cause you more problems than they are worth."
But by this time, the hobby bug had bitten me pretty hard. I kept on reading and experimenting. I came across a Canadian website that had a following of avid experimenters. They used a sophisticated freeware antenna modeling program, 4NEC2, written by Arie Voors to extend the Hoverman UHF antenna. Arie’s package is a Window’s front end to the Numerical Electromagnetics Code program originally developed in the 1970s for the US Navy at the Lawrence Livermore Laboratory. The Hoverman UHF antenna was first patented in 1959 (Patent # 2918672). These enthusiastic experimenters were searching for design improvements, finding them and then building their designs to verify the theory. Wow!!!
I tried to learn a little bit from these guys. I finally figured out how to use the 4NEC2 software at a fairly low level. I continued to independently experiment with simple and relatively small UHF antenna designs that might have some promise as an amplified indoor antenna. Fortunately for me, WGHP (FOX8) gave up on their original plans to switch their digital transmissions from UHF channel 35 back to VHF channel 8. This meant that all of the local Triad DTV stations would be transmitting in the UHF band and that greatly simplified the antenna design requirements.
Two more things I learned along the way were: 1) a low noise pre-amp like the CM-7777 goes a long ways to improve the performance of any “Do It Yourself” indoor UHF antenna, and 2) keep the RG6 coax cable as short as possible if you are not using a high quality pre-amp. An amplified indoor UHF antenna located close to each of your DTV sets can work or at least it does for me here in the Winston-Salem area.
I have several other working designs similar to the double diamond design in the picture I posted a month or so back. The best performer is a little taller than the double diamond design but has about the same size foot print. I am not exactly interested in starting a cottage industry, but on the other hand, I would love to see more folks go back to Free Over-The-Air HDTV. I am willing to demonstrate my humble efforts.