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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