----- Original Message -----
From: "Roger (K8RI)" <k8ri@rogerhalstead.com>
To: <amps@contesting.com>
Sent: Saturday, July 07, 2012 2:39 AM
Subject: Re: [Amps] Amplified TV Antenna
> On 7/6/2012 10:17 PM, W2XJ wrote:
>> To a degree, yes. It is that the newer DTV tuner chips perform better
>> under multipath conditions where NTSC was very sensitive to ghosts and
>> required a very directional antenna. With DTV, scanning does not work
>> that well when there are stations in multiple directions. In such cases
>> an omni antenna is required. When the transmitters are in one general
>> direction but not exactly in the same location, a vertically stacked
>> bowtie is best. DTV requires re-thinking what we have accepted as VHF
>> and UHF propagation.
>
> My experience is an antenna is an antenna is an antenna is an antenna.
> It makes no difference in the antenna type, they do not care whether the
> signal is analog or digital.
>
> there is no such thing as a digital or analog antenna, nor is there one
> that works better on digital or analog Vs the other
> Nor have I ever noticed a difference in types versus modes.
>
> I use very long Yagi antennas I did have two, one to the SSE and one to
> the NW. http://www.rogerhalstead.com/ham_files/tower39.htm only shows
> the one pointed to the SSE.
>
> Although it specifically a UHF antenna it worked well across the entire
> UHF spectrum. With the antenna mounted preamps they worked equally well
> on VHF from CH 2 through 13 although not very directional, but reception
> was good out to around 60 miles or more. At 90 miles you couldn't tell
> the difference between that station and a local BTW although the gain
> fell off they did well up to 60 degrees off the main axis. On axis with
> the one to the NW I could receiver Traverse city which is over 110 miles.
>
> The bow tie has been popular for two reasons. It is very broad band and
> it is *cheap*! It is rare to do weak signal work on UHF because the
> horizon + 13% is so close the signal is either strong or not there.
> Even the Radio Shack long Yagis work just fine across the entire UHF
> spectrum. When both Yagis were up I could get over 22 stations like
> they wee local. I could get Kalamazoo and GrandRapids if I swung the
> antenna 45 degrees to the SW.
>
> I did at one time have a quadrature array of them up but concluded they
> were just not worth the effort and I'd much rather have a big ham
> antenna up there. http://www.rogerhalstead.com/ham_files/tower21.htm
>
> Noise is a fact of life with Analog regardless of frequency, it just
> isn't as strong in the UHF range. I used to get both Ch 2 and Ch 50
> analog out of Detroit. That is until that religious station on channel
> 49 one came on one week after I put up a winegard dish. 50 came in
> great. A week later I could not find it because 49 was in a direct line
> with 50. They told me, you can't get 50 up there. I told them that was
> true now, but it wasn't a week ago. It didn't matter as I was too far
> out on their maps.
>
> Antennas for low and high VHF were Broadband by design. They were
> really two antennas in one. In the early days they made a lot of
> monobanders...Ie for specific channels.
When I was living on LI in the late 40's to 59 stacked bowties and folded
dipoles were common since the only direction was at NYC. The few who wanted
blacked out sports used a directional antenna with some gain and rotated to
CH3 in Hartford or hoped for a slight inversion and tried to pick up Philly
since it was an over the water shot.
When color came along the marketing ploy was that all new antennas were
needed. Now the scammers are doing it all again with DTV.
I have no problem with DTV using the same long boom Jerrold VHF/UHF L-P that
Ive had up since 1983 at 2 homes....even with a few element pieces missing..
Carl
KM1H.
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