High Def Forum - Your High Definition Community & High Definition Resource

Go Back   High Def Forum - Your High Definition Community & High Definition Resource > Local HDTV Info & Reception > Local HDTV Info and Reception
Rules HDTV Forum Gallery LINK TO US! RSS - High Def Forum AddThis Feed Button AddThis Social Bookmark Button Groups

Local HDTV Info and Reception Learn about your local HDTV stations, availability, reception issues, OTA antennas and any other local issues. RSS - Local HDTV Info and Reception

Antenna Guru's Come Inside :)

Reply
AddThis Social Bookmark Button
 
Thread Tools
Old 01-31-2013, 11:46 AM   #1
My plasma is High Def.
 

Join Date: Jan 2013
Posts: 7
Default Antenna Guru's Come Inside :)

I am looking to cut the cord as they say. I have been doing research on the forums and such and just want to see if I am on the right track. I want to install an antenna in the attic of my single story home. I know reception is better outside of the structure, but I wish to not have an exposed antenna. The home has vinyl siding an asphalt shingles. It also has two gable windows in the roof which are generally facing the transmitters I am trying to reach around the 250 degree area. I was thinking of going with a 91XG antenna with a PA-18 preamp setup. I can't post my tvfool report due to lack of 5 posts. However, There are approx 10 transmitters from 245 - 250 degrees all at 35 miles away. The signal NM(dB) ranges from 2 - 28 on these transmitters. How many of these should I be able to grab with my setup? I can PM my tvfool report if anyone is interested. Thanks so much!

Edit: I forgot to mention all of these channels are UHF that I am interested in getting.
Edit2: Scroll down for TVFool Report

Last edited by typicalmale78; 01-31-2013 at 01:09 PM. Reason: Oops
typicalmale78 is offline   Reply With Quote
Old 01-31-2013, 01:04 PM   #2
My plasma is High Def.
 

Join Date: Jan 2013
Posts: 7
Default

Post 2
typicalmale78 is offline   Reply With Quote
Old 01-31-2013, 01:05 PM   #3
My plasma is High Def.
 

Join Date: Jan 2013
Posts: 7
Default

Post 3
typicalmale78 is offline   Reply With Quote
Old 01-31-2013, 01:06 PM   #4
My plasma is High Def.
 

Join Date: Jan 2013
Posts: 7
Default

Post 4
typicalmale78 is offline   Reply With Quote
Old 01-31-2013, 01:07 PM   #5
My plasma is High Def.
 

Join Date: Jan 2013
Posts: 7
Default

Post 5
typicalmale78 is offline   Reply With Quote
Old 01-31-2013, 01:08 PM   #6
My plasma is High Def.
 

Join Date: Jan 2013
Posts: 7
Default

TVFool Report
http://www.tvfool.com/?option=com_wr...1ddabbff2abfde
typicalmale78 is offline   Reply With Quote
Old 01-31-2013, 05:03 PM   #7
High Definition is the definition of life.
 

Join Date: Jan 2008
Posts: 123
Default

I think you're on the right track (I have a 91XG in my attic). Hang the 91XG from the rafters near the very highest (central) point of your attic (within an inch of touching the roofboards) using a piece of 1" PVC pipe. Pick an attic location near where your coax would feed down to your tv to otherwise minimize coax length. When aimed toward 248 degrees true, without any amplifier, you would expect to reliably receive down to KTVI-43 and maybe down to KETC-39 from your attic, especially if aimed directly at 244 degrees true. Adding an amplifier would probably make KETC-39 more reliable (if it weren't already), and might even get reliable reception down to somewhere between WRBU-47 and KDTL-LD-16 (for stations in that general direction), with more of the weaker stations coming in better late at night and in the early morning, when atmospheric conditions favor longer-distance reception. If WRBU-47 is important, aim the 91XG closer to 239 degrees true (since it's weaker), and maximize/fine tune signal strengths with someone else looking at your tv's signal meter while switching among the channels as you tweak the aim. If you have hills in the area, consider experimenting with a 5-10 degree upward tilt with the 91XG's mounting bracket, again, as someone else checks signal strengths on the tv's meter. With WPXS-21 being off in another direction, but only 10 miles away, reception might be fine, or you might experience multipath/off-axis dropouts on that one station (tough call).

Last edited by gcd0865; 01-31-2013 at 05:08 PM.
gcd0865 is offline   Reply With Quote
Old 01-31-2013, 06:11 PM   #8
No Static At All
 
hoopitup2000's Avatar
 

Join Date: Mar 2008
Location: Northern Va
Posts: 803
Default

The construction materials of your home should allow excellent results using the 91XG. As mentioned, you may need to experiment some to get the best overall results. Getting it up as high as possible will really help.

I also have an attic mounted 91XG & am bowled over by how well it works. Experimentation with different spots in the attic was well worth the time spent.

Adding a Channel Master 3414 distribution amp really improved performance as well, even with just 1 set connected and a 40 foot coax run. Tried a few pre-amps, but the distribution amp actually does a better job once more than 1 set is connected. The 3414 is the best amplifier I have ever used. I have used them in many situations & like them better most every time when multiple splits are desired.

Last edited by hoopitup2000; 01-31-2013 at 06:31 PM.
hoopitup2000 is offline   Reply With Quote
Old 01-31-2013, 07:02 PM   #9
High Definition is the definition of life.
 

Join Date: Oct 2008
Location: Eastern Idaho
Posts: 3,069
Default

Hoopitup2000, how close is your CM3414 to the antenna?
IDRick is offline   Reply With Quote
Old 01-31-2013, 08:41 PM   #10
No Static At All
 
hoopitup2000's Avatar
 

Join Date: Mar 2008
Location: Northern Va
Posts: 803
Default

Quote:
Originally Posted by IDRick View Post
Hoopitup2000, how close is your CM3414 to the antenna?
About 30 feet. When I had the antenna outside at my previous residence, the cable run was close to 100 feet with outstanding results there as well.
hoopitup2000 is offline   Reply With Quote
Old 01-31-2013, 10:58 PM   #11
Pete
 
Pete Higgins's Avatar
 

Join Date: Aug 2012
Location: California, 58 miles @112 degrees from Mt. Wilson
Posts: 199
Default

typicalmale78

You didn’t say how many TV’s you plan to connect to the 91XG antenna? but your two highest channels are real channel 47 (668-674 MHz) & 50 (686-692) which will have ~7.587 dB attenuation (dB loss) per 100’ of coax. (.07587 dB in 1 foot). 3 dB cuts your signal in half and 6 dB cuts it to . Loss is linear with coax length and increases with frequency. Therefore, you want to locate your amplifier as close to the antenna as possible.

The 91XG lends itself to mounting a Channel Master PCT-MA2-M ultra mini drop amplifier right to the antenna with an F-71 M-M barrel connector. The basic idea is to amplify the available signal before it incurs any cable or splitter loss. These amplifiers provide +15 dB of amplification, ~ 2.7 dB NF and can be powered through the coax carrying the signal or through a separate dedicated coax power run. Best of all they are weather proof, really small and light. A four way splitter causes about 7 dB of loss/leg so if you mounted one of these at the antenna and used a 4-way splitter the signal to each TV would be approximately the same (15 dB – 7 dB = 8 dB)

I live in a deep fringe area with one strong FM and one strong PBS station 3.5 miles from my house. I ended up mounting a PCT-MA2-M to my 91XG, another to my 10 element Hi VHF antenna and a third to my 10 element FM Yagi.

Just some food for thought.
Pete Higgins is offline   Reply With Quote
Old 02-01-2013, 06:36 AM   #12
My plasma is High Def.
 

Join Date: Jan 2013
Posts: 7
Default

Thank you all for the feedback so far.

Pete- I will be connecting to two tv's for sure, but possibly 3. The two tv's will definately be less than a 50 ft run each, but probably closer to 30. I havn't actually measured it out yet considering I am not sure where the antenna will give best results in my attic as of yet.
typicalmale78 is offline   Reply With Quote
Old 02-01-2013, 05:16 PM   #13
High Definition is the definition of life.
 

Join Date: Oct 2009
Posts: 918
Default

Quote:
~7.587 dB attenuation (dB loss) per 100’ of coax. (.07587 dB in 1 foot).
Sure that's not 5.7 dB or so? If I found an RG6 cable with 7.6 dB loss/100' at 700 MHz, I'd toss it out as too lossy. 5.5 to 6 dB/100 at channel 51 is a pretty typical insertion loss for RG6.

Ah, heck! TVFool isn't working, but you're in the St Louis area, probably somewhere between St Louis and Carlyle, from the conversation.

Last edited by projectsho89; 02-01-2013 at 05:19 PM.
projectsho89 is offline   Reply With Quote
Old 02-01-2013, 10:17 PM   #14
Pete
 
Pete Higgins's Avatar
 

Join Date: Aug 2012
Location: California, 58 miles @112 degrees from Mt. Wilson
Posts: 199
Default

projectsho89

I used the Times Microwave online calculator set for RG-6 & 689 MHz. (center of channel 50) and got 7.587 dB/100'.
http://www.timesmicrowave.com/cgi-bin/calculate.pl
Their calculators cover a wide range of cable types and have been pretty accurate over the years when we swept cables from various manufactures.

Lower quality (read cheaper) and really old cable often performed somewhat worse, especially at the higher frequencies. Cables were tested with properly installed connectors on each end and results adjusted for DUT cable length.
Pete Higgins is offline   Reply With Quote
Old 02-01-2013, 10:35 PM   #15
Pete
 
Pete Higgins's Avatar
 

Join Date: Aug 2012
Location: California, 58 miles @112 degrees from Mt. Wilson
Posts: 199
Default

typicalmale78

I think I would try the 91XG in your attic to one TV without an amplifier first. A 30' run of coax should only give about 2.3 dB (or less?) of attenuation @ Ch 50. Then add a 2-way splitter (-3.5 dB of additional loss to each TV). If you get pixilation or experience intermittent reception on some channels, then you can try an amplifier. They are really easy to add later, especially in an attic.

Unless of course the ‘78’ is an age reference. I am pushing 70 and know how crawling around in the attic can leave you stove-up for a couple of days.
Pete Higgins is offline   Reply With Quote
Sponsored Links
Go Back   High Def Forum - Your High Definition Community & High Definition Resource > Local HDTV Info & Reception > Local HDTV Info and Reception
AddThis Social Bookmark Button
Reply

Thread Tools

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off


All times are GMT -6. The time now is 02:31 AM.



Copyright ©2000 - 2014, Jelsoft Enterprises Ltd.
Search Engine Optimization by vBSEO 3.6.0
Copyright 2004 - 2008, High Def Forum