That is what the theory says. In practice if the signal is above the
digital cliff it is 100%. What make life more complicated? Many people
have height, space and covenant restrictions. They in practice do what
works. I have been working with DTV for 15 years and learned what works.
It is necessary to think differently.
On 7/7/12 2:44 PM, Joe Subich, W4TV wrote:
> On 7/7/2012 1:54 PM, W2XJ wrote:
>> Most people report acceptable results on VHF with a UHF bowtie if
>> the V is relatively local.
> If you are going to erect an external antenna, use the right antenna
> for the job. In mixed U/V environments, that's a U/V antenna - not
> a UHF bowtie that just "might" work on close-in VHF signals. If you
> are going to accept whatever signal is there, the FM folded dipole
> produces signals even though it is a resistive short very close to
> one of the channels in use in the particular market.
>
> With a UHF bow-tie in a mixed U/V market, at least install a splitter
> backward as a combiner and connect a high VHF bow tie or at minimum
> a dipole cut for about 195 MHz in parallel with the UHF antenna.
>
> 73,
>
> ... Joe, W4TV
>
>
>
> On 7/7/2012 1:54 PM, W2XJ wrote:
>> Most people report acceptable results on VHF with a UHF bowtie if the V
>> is relatively local.
>>
>>
>> On 7/7/12 12:03 PM, Joe Subich, W4TV wrote:
>>> > *** And from my original question. Is it a good bet to install this
>>> > well-regarded amplified TV antenna? Bearing in mind that I will be
>>> > helpless if the internal amp suffers fundamental overload at HF?
>>>
>>> Also far removed from amplifiers and their operation - more appropriate
>>> for a DTV antennas list.
>>>
>>> > bearing in mind that we are getting very decent - but not 100% -
>>> > reception with a mere 300-ohm folded dipole "FM Antenna" tacked to the
>>> > wall.
>>>
>>> A twinlead folded dipole "FM Antenna" (88-108 MHz) is not very good
>>> on UHF TV (450-900 MHz). It has a widely varying pattern and on some
>>> channels appears as a resistive short across the receiver input.
>>>
>>> If you get any where near acceptable signals with the FM dipole, all
>>> stations are in a single direction (+/- 45 degrees or so), and all
>>> stations are UHF (actual channel - not the virtual channel they ID),
>>> then a two or four bay bow-tie antenna will be more than enough and
>>> probably far more reliable than the amplified omni. On the other
>>> hand if you are in one of those places "between" transmitter sites
>>> (with clusters in opposite directions) you're likely stuck with an
>>> omni (or multiple directional) antennas.
>>>
>>> Start your search at:
>>> http://www.antennaweb.org
>>> http://www.antennapoint.com
>>> http://transition.fcc.gov/mb/engineering/maps/
>>>
>>> Your area has two high VHF channels and many UHF channels (19-47).
>>> Fortunately, other than one distant independent, they seem to be
>>> clustered in two directions with less than a 30 degree spread.
>>> You would probably be best served by a small VHF/UHF dualband
>>> log-periodic - a UHF "bow tie" antenna would be questionable for
>>> the two VHF stations.
>>>
>>>
>>> 73,
>>>
>>> ... Joe, W4TV
>>>
>>>
>>>
>>> On 7/7/2012 11:19 AM, Jerry Kaidor wrote:
>>>>> In any case, all of this is rather far removed from amplifiers.
>>>>>
>>>> *** And from my original question. Is it a good bet to install this
>>>> well-regarded amplified TV antenna? Bearing in mind that I will be
>>>> helpless if the internal amp suffers fundamental overload at HF? Or
>>>> should I just pack it off back to Amazon and install something like a
>>>> bowtie - bearing in mind that we are getting very decent - but not 100% -
>>>> reception with a mere 300-ohm folded dipole "FM Antenna" tacked to the
>>>> wall.
>>>>
>>>> - Jerry Kaidor, KF6VB
>>>>
>>>>
>>>>
>>>>
>>>>
>>>>
>>>>
>>>>
>>>>
>>>>
>>>>
>>>>> 73,
>>>>>
>>>>> ... Joe, W4TV
>>>>>
>>>>>
>>>>>
>>>>> On 7/7/2012 7:18 AM, W2XJ wrote:
>>>>>> You got what you got. In most cases the antenna had to be adjusted for
>>>>>> each channel. With DTV this is not very practical as the TV must scan
>>>>>> the channels seen by the antenna at that instant.
>>>>>>
>>>>>>
>>>>>> On 7/7/12 7:01 AM, Bill Turner wrote:
>>>>>>> ORIGINAL MESSAGE:
>>>>>>> On Fri, 06 Jul 2012 22:19:21 -0400, you wrote:
>>>>>>>
>>>>>>>> I disagree. No one in their right mind would have used an omni to
>>>>>>>> receive NTSC.
>>>>>>> REPLY:
>>>>>>> What about those hundreds of millions of portable TVs with "rabbit
>>>>>>> ears" or
>>>>>>> monopole verticals?
>>>>>>>
>>>>>>> 73, Bill W6WRT
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>>>>
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