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post #11251 of 11265 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 11265 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 11265 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?

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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 11265 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 11265 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 11265 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 11265 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.

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post #11258 of 11265 Old 09-29-2014, 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 11265 Old 09-29-2014, 07:04 AM
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Quote:
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; 09-29-2014 at 09:18 AM.
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post #11260 of 11265 Old 09-30-2014, 02:47 PM
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Thought I would post in this thread as well related to KCBA. I live in Gilroy and have an antenna in the attic (I know get it outside...). KCBA worked 99% of the time until 2-3 weeks ago where it began to drop out for hours to a day at a time. It is now completely gone.

I think I had a failure in the antenna (UHF/VHF combo C2) so I swapped it out for a CM4228HD. At my old house I had a CM4228 that faired well in the attic at 15 miles further away so I thought this would be a good option even though it is not as good as the old revision. Even with the CM4228HD and a CM7777 or CM7778 pre-amp I can't get KCBA back. I tried with no pre-amp as well to verify I was not overloading. I am thinking there is something happening with either the signal strength or a change between the tower where KCBA is located and where I am.

broken URL due to post count. They must have purged older posts....
www . tvfool . com/ ?option=com_wrapper&Itemid=29&q=id%3dd243cfde4ab69 1


I can get 8.* and 25.* but not 35.1.

I would love to pull channels from Sutro with the antenna outdoors but I have a wall of 30-40 foot trees lining a field that may interfere with any signal from the north. It might be possible but I fear intermittent.
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post #11261 of 11265 Old Yesterday, 07:10 AM
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Quote:
Originally Posted by Dewmerz View Post
Thought I would post in this thread as well related to KCBA. I live in Gilroy and have an antenna in the attic (I know get it outside...). KCBA worked 99% of the time until 2-3 weeks ago where it began to drop out for hours to a day at a time. It is now completely gone.

A CM4228 is a UHF antenna and KCBA is on VHF 13 so that antenna is not going to work for you. And yes, it should be outdoors. You must be in a really bad spot to have Mt. Toro (KION, etc.) so far down the list and have KCBA at 2 edges. Can you receive KION? TV Fool says no.

No Sutro station appears on your list anywhere so that means it is likely to be impossible.

Chuck


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post #11262 of 11265 Old Yesterday, 05:07 PM
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Originally Posted by Calaveras View Post
A CM4228 is a UHF antenna and KCBA is on VHF 13 so that antenna is not going to work for you. And yes, it should be outdoors. You must be in a really bad spot to have Mt. Toro (KION, etc.) so far down the list and have KCBA at 2 edges. Can you receive KION? TV Fool says no.

No Sutro station appears on your list anywhere so that means it is likely to be impossible.

Chuck
KION at 2edge has not worked for me with either antenna in the attic. I am close to the west hills so there may not be a direct line of site to the tower.

I know the CM4228 is not optimal for VHF but it gets 8 with signal strength of 94 using the 7778 and 35-40 with no pre-amp. I would ditch the UHF antenna and go just VHF if I did not need PBS for the kid on 25.1.

Hoping to test outdoors this weekend.

Thanks,
Brian
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post #11263 of 11265 Old Yesterday, 05:36 PM
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Originally Posted by Dewmerz View Post
KION at 2edge has not worked for me with either antenna in the attic. I am close to the west hills so there may not be a direct line of site to the tower.

I know the CM4228 is not optimal for VHF but it gets 8 with signal strength of 94 using the 7778 and 35-40 with no pre-amp. I would ditch the UHF antenna and go just VHF if I did not need PBS for the kid on 25.1.

Hoping to test outdoors this weekend.

Thanks,
Brian
Anyone in Morgan Hill/Gilroy on the west side has a hard time. The east side is much better. Why don't you get a Winegard HD7698P or an HBU55 and mount it outdoors? One antenna, UHF and VHF. You'd be okay with a preamp too. Using a UHF antenna on VHF only works when the signal is very strong. KBCA has much reduced power to the north which is why TV Fool shows it as 24 dB weaker than KSBW. BTW, K46LG at the top of your list is not located where TV Fool says it is. It's on Fremont Peak.

Chuck


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post #11264 of 11265 Old Yesterday, 05:47 PM
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Originally Posted by Calaveras View Post
Anyone in Morgan Hill/Gilroy on the west side has a hard time. The east side is much better. Why don't you get a Winegard HD7698P or an HBU55 and mount it outdoors? One antenna, UHF and VHF. You'd be okay with a preamp too. Using a UHF antenna on VHF only works when the signal is very strong. KBCA has much reduced power to the north which is why TV Fool shows it as 24 dB weaker than KSBW. BTW, K46LG at the top of your list is not located where TV Fool says it is. It's on Fremont Peak.

Chuck
Thanks Chuck. Good to know the west side is harder by default. I will look into the antennas suggested. I guess I had a good 2 year run before it decided to drop out.

Thanks,
Brian
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post #11265 of 11265 Old Yesterday, 05:57 PM
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Quote:
Originally Posted by Dewmerz View Post
KION at 2edge has not worked for me with either antenna in the attic. I am close to the west hills so there may not be a direct line of site to the tower.

I know the CM4228 is not optimal for VHF but it gets 8 with signal strength of 94 using the 7778 and 35-40 with no pre-amp. I would ditch the UHF antenna and go just VHF if I did not need PBS for the kid on 25.1.

Hoping to test outdoors this weekend.

Thanks,
Brian
Dewmerz, I feel your frustration regarding KCBA. I'm out by Lake Anderson, and it's quite tough here...

If you decide to get a VHF only antenna, I have essentially a new Y10-7-13. I paid about $55 delivered, which is pretty good. 30 bucks, if interested...

My strongest PBS is on virtual 54. Not sure if that is better for you... I believe the transmitter is in Milpitas.
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