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Thread: New Antenna Blog by Phil Karras KE3FL

  1. #1
    Join Date
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    Mount Airy, MD, USA
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    New Antenna Blog by Phil Karras KE3FL



    Greetings!

    I've been offered a volunteer guest blogger position here at Solid Signal and have been contemplating just what to write about.

    I'm a physicist by education and have worked in the optical, fluid dynamics, high-powered LASER as well as all manner of IT and software development fields. I am probably what was once called a "jack of all trades, master of none." However, my level of "jacking" can rise to that of a master when my interest is focused on any particular subject long enough. Or, at least, I hope it can.

    My hobbies include Amateur Radio (Ham Radio) and my interests are in the antenna designing, building, construction side of ham radio as well as general radio and TV, with some circuit design and building thrown in for good measure.

    In the last few years I've helped others get the TV stations back that they lost with the change to DTV. I have been trying various TV antennas to get back my own lost TV signals from Washington D.C.

    I live in a small Carroll County, MD, town called Mount Airy. Looking up the TV stations I should be able to receive (as purported on TV Fool using the "Check Your Address for Free TV" link), I was originally hopeful that I could receive all of the stations I was able to receive when there was analog TV. When we bought our present home in March 1991, we were told by the former owner that we could receive all TV stations from both Baltimore and Washington, D.C., with a TV and a "rabbit ears" antenna. This was mostly true for the VHF stations but not so for the UHF stations, especially those from Washington.

    Most of you have probably experienced the same disappointing DTV reception characteristics and have concluded, as I have, that the theory that these calculations are based on was, and still is, overly optimistic. I quickly discovered that not only couldn't I get all of the stations as easily as I used to, but there are some that are extremely difficult to receive now. In fact, with a rabbit ears antenna and the portable DTV in the living room, I receive only one Baltimore station well enough to actually be worth watching.

    This, then, is my situation and I will write about my experiences using various ideas, antennas, and combinations in different situations in the hope of helping you get your free TV back to where it once was.

    All of my TV antenna articles have been published in Popular Communication magazine, starting with a Turnstile-Bow-Tie UHF antenna I designed, built, tested, and then used for years to get the missing UHF NTSC/analog TV stations in my area from both cities. This particular design has the advantage that no rotator is needed in order to get stations from completely different directions. In my case, Baltimore is East and Washington is South.

    Disclaimer: I am not here to sell Solid Signal, or anybody else's DTV products. I am not being paid for this blog, nor do I care if I hurt the feelings of any particular manufacturer. I will tell it as I find it, and if any seller or manufacturer does not like that, that's not my concerned. I am not here to make enemies, but I'm also not here to make friends or to whitewash someone's pet product. I consider myself to be a very interested but unbiased observer.

    Last, my next installment will be a proposal of antenna tests I will be working on with my present antennas designs & TV antennas I already own. I will test other antennas against the ones I have & can characterize. I hope you will help me here with suggestions and comments as to whether or not what I'm doing will be helpful to you.

    That's it for this time around. In the meantime, you can contact me through my Ham Radio (KE3FL) web site and visit it to get an idea of the things I've done, am doing, and am interested in.

    Until next time, Good viewing & listening!
    Phil Karras, KE3FL / KPC3FL
    http://cs.yrex.com/ke3fl

  2. #2
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    As they say: I like where you're coming from.

    I too got burned by antennaweb back in 2003 as they hadn't added terrain to their modeling.
    As such they claimed I could get reception from stations in Reno, but failed to account for something called the Sierra Nevada mountain range.

    Antennaweb has since added terrain to their modeling.

    "I'm curious" as to what you think I might receive with this:

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  3. #3
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    Quote Originally Posted by VOS View Post
    As they say: I like where you're coming from.
    "I'm curious" as to what you think I might receive with this:
    In looking at it & comparing to what I know about my area and how TVFool rated everything here I would say it would be difficult to get anything without a very good high-gain (very directional) antenna and up as high as you can get it. But, I haven't yet tried my new homebrew TV antennas up on my roof yet so I can't really say if something like that would work for you or not.

    When I started trying this a few years ago after the DTV switch TVFool said that there were 15 stations that should have been receivable with only an indoor "set-top" antenna. I got and can still get only one well enough to watch. These were all rated at -55 dBm or higher (up to -31 dBm). Your listing shows all stations at -90 dBm or worse.

    What have you tried and have you found anything that works? If so, include a list of the TV stations you can get and at what quality.

    I eventually came up with a relative rating system that started out as Good, OK, Poor, Bad and went to WW, NWW. WW = Worth Watching, and NWW = Not WW. I feel that the analog TV was far better at gracefully slipping over into the NWW category so that Excellent, Very Good, Good, Poor, Bad, Really Bad was a perfectly good rating system.

    With DTV if the picture pixilated too often and/or it lost audio too often it simply was not worth watching. While they said that we'd get everything we got before but with better quality, the truth was that the reception didn't even come close to getting what was possible before and most of what was receivable was in the "not worth watching" category. And even that was with a better antenna arrangement than was needed before.

  4. #4
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    Analog was much more forgiving than digital is. "A little fuzz" went by almost unnoticed.

    I must come clean, as my question was VERY loaded.

    Same location but with an "imaginary" 300' mast:



    Yes I did get most/all of the channels out of Sacramento, but weather had a lot of affect and sometimes when I couldn't get channels that were 62 miles away, I could get those from 120 miles away.

    I had about 20 dBi of antenna gain and 28 dB of preamp.
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  5. #5
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    I'm not trying to suggest TVFool is the be all end all to find which channels you should get, but the terrain modeling has improved their results.

    Here's what it reports with various mast heights at one location:



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  6. #6
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    Quote Originally Posted by VOS View Post
    Analog was much more forgiving than digital is. "A little fuzz" went by almost unnoticed.

    I must come clean, as my question was VERY loaded.

    Same location but with an "imaginary" 300' mast:



    Yes I did get most/all of the channels out of Sacramento, but weather had a lot of affect and sometimes when I couldn't get channels that were 62 miles away, I could get those from 120 miles away.

    I had about 20 dBi of antenna gain and 28 dB of preamp.
    Just a quick note: Weather affects the UHF band more than the VHF or even lower bands as you may know. As for the gain in your antenna & amplifier, the 20 dBi of antenna gain is the only gain that will help get a DTV signal. The amplifier can only amplify what it gets at it's input. The only gain that is needed in the amplifier is the gain needed to offset the losses in the coax & connections.

    I think I'll write more about this & post it to the blog since this is another good topic and many people simply do not understand amplifiers and how to determine what is needed and where.

    Phil KE3FL

  7. #7
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    Quote Originally Posted by PhilK View Post
    The only gain that is needed in the amplifier is the gain needed to offset the losses in the coax & connections.

    I think I'll write more about this & post it to the blog since this is another good topic and many people simply do not understand amplifiers and how to determine what is needed and where.

    Phil KE3FL
    The antenna was over 120' from the tuners and the signal was split to feed a few tuners.

    I hope this has given you some good ideas for your blog.

    This isn't my first roundup.

  8. #8
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    Quote Originally Posted by VOS View Post
    The antenna was over 120' from the tuners and the signal was split to feed a few tuners.

    I hope this has given you some good ideas for your blog.

    This isn't my first roundup.
    Yes, this has given me at least two topics to write about

    Thanks VOS,
    Phil KE3FL

  9. #9
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    Maybe some would like to read more about these:




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