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post #11251 of 11259 Old 09-24-2014, 05:20 PM
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Quote:
Originally Posted by TonyB1966 View Post
I plan to dedicate some time to this soon... If there's any good reading on this subject, please share. certain frequencies, VHF vs UHF,
www.hdtvprimer.com/antennas/siting.html

Easy to understand link ... on the subject.
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post #11252 of 11259 Old 09-24-2014, 05:39 PM
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Originally Posted by Calaveras View Post
I have to take exception to this. I've never seen any evidence that wind makes any difference unless you're looking through vegetation and then movement of the vegetation will affect UHF more than VHF.

Chuck
You are correct. ... I forgot to state what the wind does. (to trees)
The link below shows the smaller UHF signal -versus- VHF signal through trees.
So forum readers can visualize the wind "moving tree"(s) = moving signal type of UHF dropouts.
www.hdtvprimer.com/antennas/siting.html

I would guess the wind would need to move the tree foliage 10 to 20 feet or more to impact VHF reception.
For UHF, the wind moves the foliage "beyond the size range" of a UHF antenna. Bowtie size, loop size, etc.
creating an "ongoing" multipath condition with no correction until extreme wind stops.
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post #11253 of 11259 Old 09-24-2014, 10:06 PM
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What about wind blowing dust around where it normally woudln't be would that be negligible?

Quote:
Originally Posted by 888CALLFCC View Post
You are correct. ... I forgot to state what the wind does. (to trees)
The link below shows the smaller UHF signal -versus- VHF signal through trees.
So forum readers can visualize the wind "moving tree"(s) = moving signal type of UHF dropouts.
www.hdtvprimer.com/antennas/siting.html

I would guess the wind would need to move the tree foliage 10 to 20 feet or more to impact VHF reception.
For UHF, the wind moves the foliage "beyond the size range" of a UHF antenna. Bowtie size, loop size, etc.
creating an "ongoing" multipath condition with no correction until extreme wind stops.
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post #11254 of 11259 Old 09-24-2014, 10:15 PM
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Originally Posted by Calaveras View Post
You cannot just combine two UHF antennas pointed in different directions, especially different models. They'll just interfere with each other. The Jointenna was intended to combine one channel from one antenna with most of the channels from another antenna. Channel Master no longer makes those. You can get a similar device from Tin Lee Electronics.

If you want two antennas in different directions then your best bet is separate downleads with an A/B switch in the house. Alternately you use an antenna rotor.

Chuck
I have success combining as long as one signal is much stronger than the other and the stronger signal is much higher quality or else yes you can get it bouncing back and forth or the lower quality signal can take over. And the combiner will lower the strength slightly if you are on the fringe. So I wouldn't say you can't do it, but you need to be careful when you do it.
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post #11255 of 11259 Old 09-25-2014, 12:49 AM
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I've tried combining lots of different antennas using combiners and backward splitters trying to get stations from different directions to come in on one connection. No matter what I've done, it just didn't work. You let lower signal levels and A LOT more multipath. One station might be better, but most are worse with the combining.

A few years back I used a Jointenna for channel 12 when KNTV was transmitting from Loma Prieta. I had a 10 element channel 12 antenna combined with the C5/CM4228 and it worked great. I was getting a 27 dB signal from channel 12 55 miles away. When they moved their transmitter to Mt. San Bruno I no longer needed the channel 12 antenna so removed it from the system.

(If anyone wants the channel 12 yagi, you can have it for free. Just contact me and come and pick it up. It's hanging from the ceiling down in the basement.)

The best results I've come up with for picking up stations from different directions is by using separate antennas into A-B-C switches like Chuck recommended. I have the LP345, the Y-10-7-13/4228, and the S-15 going into distribution amps that then go into three A-B-C switches that feed the living room TV, the DVR and the Home Run HD receiver. I can feed any of those antennas into any of the receivers.

My C5/4228 combination feeds the Home Run HD and the bedroom and office TVs separately.

Larry

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Last edited by Larry Kenney; 09-25-2014 at 12:55 AM. Reason: typo
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post #11256 of 11259 Old 09-25-2014, 06:37 AM
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Quote:
Originally Posted by Monte324 View Post
I have success combining as long as one signal is much stronger than the other and the stronger signal is much higher quality or else yes you can get it bouncing back and forth or the lower quality signal can take over. And the combiner will lower the strength slightly if you are on the fringe. So I wouldn't say you can't do it, but you need to be careful when you do it.

On a forum like this I can only give advice that I think will be true most of the time. You can always find someone in some situation that is successfully doing something that goes against good practice. I have a friend in Walnut Creek who successfully receives all the Sacramento stations with a dipole made out of tin foil stuck to the back of his TV. But I would never recommend this to anybody.

Chuck


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post #11257 of 11259 Old 09-28-2014, 04:12 PM
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Another scan,...another day....no KTVJ


And no KOTR - 11 too

no signal on RF 4,5,6 & 11
Filler up.

Last edited by 888CALLFCC; 09-28-2014 at 04:20 PM.
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post #11258 of 11259 Old Yesterday, 12:17 AM
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Quote:
Originally Posted by 888CALLFCC View Post
Another scan,...another day....no KTVJ


And no KOTR - 11 too

no signal on RF 4,5,6 & 11
Filler up.
I keep looking too. There are Construction Permits for all of those empty VHF channels, and 13, too, I just found out, but it's way up in Cloverdale.

There are also CP's pending for 2 on Loma Prieta, 20 on Mt. Allison, 21 on Fremont Peak and 32 on Sutro Tower (a Distributed Transmission System second transmitter for KEMO). We'll keep an eye out for those stations, too.

Larry

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post #11259 of 11259 Old Yesterday, 07:04 AM
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Originally Posted by Larry Kenney View Post
I keep looking too. There are Construction Permits for all of those empty VHF channels, and 13, too, I just found out, but it's way up in Cloverdale.

There are also CP's pending for 2 on Loma Prieta, 20 on Mt. Allison, 21 on Fremont Peak and 32 on Sutro Tower (a Distributed Transmission System second transmitter for KEMO). We'll keep an eye out for those stations, too.

Larry

I wonder if KMUV will ever come on RF 21? They're now on the KION transmitter using VC 23.1. The KION/KMUV partnership is highly advertised on 46.1.

Chuck


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Last edited by Calaveras; Yesterday at 09:18 AM.
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