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Old 6-Jan-2019, 10:36 PM   #1
Kinetic
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Antenna Signal Help/Advice

Tv Fool Report:
http://www.tvfool.com/?option=com_wr...9038d0655ada02

I've got a Winegard HD7694P installed right now, about 25ft high. No pre-amp. I'm struggling to maintain good signal strength with a couple of channels (Fox, ABC, PBS) which are 40-46 miles away. Could I just add a mast-mounted pre-amp and solve the issue, or is a different antenna recommended? Thanks for the help!
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Old 7-Jan-2019, 2:54 AM   #2
rabbit73
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Hello again, Kinetic. It looks like you are in a different location (Boerne?) than in your last thread:
Roof-top Antenna recommendation
http://forum.tvfool.com/showthread.php?t=15983

Thank you for the signal report. You say your antenna is 25ft high, but you used 10ft for your signal report. Please redo your report at 25 ft; it makes a difference with 2Edge signals.

A preamp will help with the weak 2Edge Fox signal at 140 degrees, but it might be overloaded by KNIC at 115 degrees. A more directional UHF antenna might be necessary. Try a medium gain preamp that is less likely to be overloaded than a high gain preamp, before switching antennas. Perhaps an Antennas Direct Juice or a Channel Master 7778.

ABC and PBS are VHF, so you might be able to use the 7694 just for VHF or have a separate VHF antenna.
Attached Images
File Type: jpg KineticTVFmap1-6-2019.JPG (93.0 KB, 313 views)
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Last edited by rabbit73; 7-Jan-2019 at 3:26 AM.
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Old 7-Jan-2019, 4:08 PM   #3
Kinetic
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Quote:
Originally Posted by rabbit73 View Post


Hello again, Kinetic. It looks like you are in a different location (Boerne?) than in your last thread:
Roof-top Antenna recommendation
http://forum.tvfool.com/showthread.php?t=15983

Thank you for the signal report. You say your antenna is 25ft high, but you used 10ft for your signal report. Please redo your report at 25 ft; it makes a difference with 2Edge signals.

A preamp will help with the weak 2Edge Fox signal at 140 degrees, but it might be overloaded by KNIC at 115 degrees. A more directional UHF antenna might be necessary. Try a medium gain preamp that is less likely to be overloaded than a high gain preamp, before switching antennas. Perhaps an Antennas Direct Juice or a Channel Master 7778.

ABC and PBS are VHF, so you might be able to use the 7694 just for VHF or have a separate VHF antenna.
Thanks for the reply! Here is my updated report:

http://www.tvfool.com/?option=com_wr...903848254225bd

I can try the amp and see if that works. Is there a better antenna recommendation you could give? Were you suggesting getting a separate antenna for UHF reception?

If this were a "start from square one"scenario, what might you recommend?
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Old 8-Jan-2019, 6:22 PM   #4
rabbit73
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Quote:
Originally Posted by Kinetic View Post
Thanks for the reply! Here is my updated report:

http://www.tvfool.com/?option=com_wr...903848254225bd
Thank you for the new report at 25ft.



WOAI NBC isn't on your TVFool report. As a double check, here is a report from rabbitears.info:



As a result of repack by the FCC, there will be some channel changes, as indicated by the arrows:
https://www.rabbitears.info/market.p...&callsign=WOAI

WOAI NBC will move from real channel 48 to 28.
KENS CBS from 39 to 29.

This is the repack plan for San Antonio:
https://www.rabbitears.info/repackch...=&lss=&status=

Most of the changes will be during Phase 3, 4/13/2019 to 6/21/2019.
https://www.fcc.gov/about-fcc/fcc-in...ition-schedule

https://www.commlawcenter.com/2017/0...deadlines.html
Attached Images
File Type: jpg KineticTVFreport1-7-2019.JPG (104.6 KB, 207 views)
File Type: jpg KineticTVFreportRE.JPG (181.6 KB, 207 views)
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Old 8-Jan-2019, 8:22 PM   #5
rabbit73
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This is the terrain profile for KABB showing the terrain interference to the signal. Any increase in antenna height helps the signal clear the hills.



The TVFool Interactive map was used to show change in NM at various heights
http://www.tvfool.com/index.php?opti...pper&Itemid=90

This shows the coverage of the KABB signal at your location:



Attached Images
File Type: jpg KineticTVFp2KABB.JPG (125.4 KB, 195 views)
File Type: jpg KineticTVFcovKABB.JPG (114.8 KB, 194 views)
File Type: jpg KineticTVFcovKABBcu.JPG (141.4 KB, 193 views)
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Old 8-Jan-2019, 10:36 PM   #6
Kinetic
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You really outdid yourself! Thank you so much for providing this information. I'm bookmarking all this stuff for future reference. So it seems that I'm not in an ideal location to receive a strong signal for many of the San Antonio stations.

Thank you so much for the feedback and info!
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Old 9-Jan-2019, 12:00 AM   #7
rabbit73
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Quote:
Originally Posted by Kinetic View Post
So it seems that I'm not in an ideal location to receive a strong signal for many of the San Antonio stations.
That is true, you are not in an ideal location to receive them, but I have a few ideas you might want to try.

You need a preamp for the weaker channels from San Antonio, but KNIC is strong enough to cause overload. You could order a custom bandstop filter to attenuate real channel 18, but ChannelPlus makes a notch filter that is less expensive which might work.



Code:

                               Grounding
HD7694 > NF-469 > Juice > coax > Block > coax > Power > TV
                  Preamp                       Inserter

Grounding the coax with a grounding block makes the filter more effective.
If the antenna is outside, the coax shield should be grounded with a grounding block that is connected to the house electrical system ground with 10 gauge copper wire for electrical safety and to reject interference. For further compliance with the electrical code (NEC), the mast should also be grounded in a similar manner to drain any buildup of static charge which will tend to discourage a strike, but the system will not survive a direct strike.

Attached Images
File Type: jpg ChannelPlus NF-469curve3.jpg (154.6 KB, 184 views)
__________________
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Last edited by rabbit73; 9-Jan-2019 at 12:10 AM.
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Old 9-Jan-2019, 12:52 AM   #8
rabbit73
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Quote:
Originally Posted by Kinetic View Post
If this were a "start from square one"scenario, what might you recommend?
Interesting question. There a number of possibilities, none of which I can guarantee, because I don't even know what your location looks like from the ground or in a satellite view.

I would probably consider a two-antenna solution, one for UHF and one for VHF-High. The UHF antenna would be an HDB91X because it has a narrow beamwidth to help reject KNIC when it is aimed at San Antonio and has a tilt feature that would allow you to tilt the front end of the antenna up. The upward tilt might help capture the signals coming down from the peak of the hill that is just before your location.
https://www.solidsignal.com/pview.asp?p=hdb91x

The VHF antenna would be a Stellar Labs 30-2475
https://www.newark.com/stellar-labs/...vhf/dp/48Y8141

Code:


 HDB91X  
     \               Juice         Grounding
     UVSJ > NF-469 > Preamp > coax > Block > coax > Power > TV
     /      Filter                                 Inserter
30-2475  

Protect filter from weather
UVSJ UHF/VHF Combiner
https://store.antennasdirect.com/UHF...Combiners.html
__________________
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Last edited by rabbit73; 9-Jan-2019 at 12:57 AM.
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Old 9-Jan-2019, 6:47 PM   #9
Tower Guy
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Quote:
Originally Posted by rabbit73 View Post
I would probably consider a two-antenna solution, one for UHF and one for VHF-High. The UHF antenna would be an HDB91X because it has a narrow beamwidth to help reject KNIC when it is aimed at San Antonio and has a tilt feature that would allow you to tilt the front end of the antenna up.

The VHF antenna would be a Stellar Labs 30-2475
https://www.newark.com/stellar-labs/...vhf/dp/48Y8141
I notice a significant difference between the signal level of KNIC calculated by tvfool.com and RabbitEars.info. Tvfool shows KNIC 48.3 dB stronger than FOX while RabbitEars says 32.3 dB. That makes it hard to determine if preamp overload would exist or not. I would doubt overload will occur with a Juice preamp.

The HD7694P is a pretty good VHF antenna. Probably similar to the Stellar Labs VHF antenna.

I’d try a preamp before a new antenna. If that doesn’t work I’d try an HD7698P as that has about 2 dB more gain on VHF than the 7694 plus has about 4 dB less reception at 25 degrees off axis on channel 18 as well as several more dB gain on UHF.

Another option is to find if another location or height works better with your existing antenna. ( read “siting the antenna” in hdtvprmer.com)

Last edited by Tower Guy; 9-Jan-2019 at 6:50 PM.
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