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The Official AVS Antenna and Related Hardware Topic! - Page 482

post #14431 of 15407
Quote:
Originally Posted by arxaw View Post

That's a great price on the ANT751.

Do you think that antenna would help me receive channel 12? I'm currently using a home-made 4-bay in the attic. I can get all the channels to the south that I want except 12. I don't know why but I can get channels 6 and 9 with the 4-bay. Channel 9 comes in from the back of the antenna but I don't care if I lose that one.

TV Fool Report
post #14432 of 15407
If VHF channels are strong enough, any piece of metal may pick them up; even a 4bay antenna tuned mostly for the UHF band. That's why you're getting 6 & 9 with yours. The signals are fairly strong. Ch 12 at your location is weaker, so the 4bay UHF isn't receiving sufficient signal, but the ANT751 should pick it up, unless some sort of attic materials are blocking it. Outdoor would really be better.

If you're getting lowband VHF ch 6 with your current UHF 4-bay, the ANT751 will likely also pick it up at your location, even though it is tuned for VHF-HI and UHF, not VHF-LO. No guarantee, though, as ch 6 is often hit or miss without an antenna specifically tuned for lowband VHF. A better choice for you may be the Winegard HD7000R, which is similar to the ANT751, but is tuned for all 3 TV bands.
post #14433 of 15407
Quote:
Originally Posted by arxaw View Post

A better choice for you may be the Winegard HD7000R, which is similar to the ANT751, but is tuned for all 3 TV bands.

Thanks. Since the HD7000R is 100" wide I can't put it in the attic. I'm going to try the ANT571 first. If that doesn't work I'll try the HD-7000R outdoors when the weather gets better.
post #14434 of 15407
You didn't say which DIY 4-Bay design you used.

M4 Super-4-Bay Bowties have very good Hi-VHF Gain, F/B & F/R Ratios,
however the way too small 4-Bay antennas such as DB-4 and the
notorious U-Tube Defect have not only poor UHF performance, but
what little Hi-VHF Gain it can muster is pointed towards the REAR:
http://imageevent.com/holl_ands/mult...ayrefl/db4refl

It is also important to note that ALL of these UHF 4-Bay antennas
have excessive SWR trying to operate in the Hi-VHF Band. Inserting
a short length of coax (e.g. 18-24 inches) could "shift" a NULL on the
end of the coax to another frequency. But the digital decision process
may still be degraded due to the Error Vector Magnitude (EVM) effect
[search forum & Google for more info).
post #14435 of 15407
Quote:
Originally Posted by holl_ands View Post

You didn't say which DIY 4-Bay design you used.

It's the "notorious U-Tube Defect" design.
post #14436 of 15407
Build plans and kits for the M-4 bow-tie array are here: http://m4antenna.eastmasonvilleweather.com/index.html. By what shows in your TVFool report, you could rebuild your bowtie array for better results.
post #14437 of 15407
Quote:
Originally Posted by meschaefer View Post

Hi folks,

I have been doing a lot of research, but it appears that this is a can be a very big and technical topic. So I thought I should just ask for some help. I am looking to set an Antenna up on my roof. I live in fairly urban environment and there are some buildings around me that are taller than mine, but that being said it also appears from my tvfool report that I have some fairly strong signals. My initial thought is to just go big and tall, but that may be overkill and unnecessary. Initially this will be going to one TV, with a run of about 60 foot of RG6, mostly depending where on the roof the antenna goes. Any thoughts on an antenna choice would be greatly appreciated.

http://www.tvfool.com/?option=com_wr...0b8690fde8ba36


I just wanted to report back, that I went with the RCA ANT751 as recommended. I put it up on top of my roof and fabricated a 10 foot extension for the mast (Which gets it up about 40 foot in the air and over the apartment building right next to me) and aimed it at 254° magnetic compass direction. Did a scan, and pulled in approx 65 channels. (Granted most are crap) I am pulling in all of my network channels at full strength with a great picture. Best Superbowl picture I ever had.

Thanks for your help.

Matt
post #14438 of 15407
Quote:
Originally Posted by Ken.F View Post

It's the "notorious U-Tube Defect" design.

If it has a Reflector, my comments above apply....
However, with NO Reflector, U-Tube Defect provides 3.2 dBi, Bi-Directional Gain for Hi-VHF,
although the SWR is Excessive (just like UHF):
http://imageevent.com/holl_ands/multibay/4bay/utube
post #14439 of 15407
Quote:
Originally Posted by holl_ands View Post

If it has a Reflector, my comments above apply....
However, with NO Reflector, U-Tube Defect provides 3.2 dBi, Bi-Directional Gain for Hi-VHF,
although the SWR is Excessive (just like UHF):
http://imageevent.com/holl_ands/multibay/4bay/utube

I've played around with a piece of foam board covered with aluminum foil as a reflector. The reflector blocks channel 9 from the north. If I add the reflector and space it about 5 inches back I can sometimes get 12 but it makes 6 less stable. With the reflector spaced about 1-1/2 inches back I get 6 reliably but I lose 12.

I picked up the ANT751 today. I'll put it up tonight if I have time.
post #14440 of 15407
Quote:
Originally Posted by Dave Loudin View Post

Build plans and kits for the M-4 bow-tie array are here: http://m4antenna.eastmasonvilleweather.com/index.html. By what shows in your TVFool report, you could rebuild your bowtie array for better results.

Thanks for the suggestion. I already have that page bookmarked. I thought some day I might try building one of those or a Gray-Hoverman. Then I saw jschweda19 mention the ANT751 being on sale for about what it would cost me to build another antenna.
post #14441 of 15407
Quote:
Originally Posted by meschaefer View Post

I just wanted to report back, that I went with the RCA ANT751 as recommended. I put it up on top of my roof and fabricated a 10 foot extension for the mast (Which gets it up about 40 foot in the air and over the apartment building right next to me) and aimed it at 254° magnetic compass direction. Did a scan, and pulled in approx 65 channels. (Granted most are crap) I am pulling in all of my network channels at full strength with a great picture. Best Superbowl picture I ever had.

Thanks for your help.

Matt

Matt, glad the ANT751 worked for you. Thanks for posting back with your results.

It's true that many of the OTA channels are "crap," but so are many cable channels. And amazingly, people actually pay money for that crap. At least OTA is free (after you pay for the equipment).
post #14442 of 15407
Hey, Ken.F, if you want to consider G-H's further, be sure to bookmark this site. Design parameters were run through an optimizer to get around 14dBi gain in the UHF band and 9dBi in the hi-VHF band.
post #14443 of 15407
I put the ANT751 up. When I can get a helper to come over I'll be able to aim it better. I pointed it in the same general direction the 4-bay was facing and it seems to be working well. I still get WBPH on 9 from the north even though the antenna is pointed south. I have some tall pine trees to the south-east so maybe it's bouncing the signal off the trees?

12 is better now but I don't know how solid that one will be. Time will tell. Right before swapping the antennas I was getting it at 14-18 on the signal meter. The picture starts to break up at about 16 so this was a good time to swap antennas. The ANT751 is pulling it in at 20-22 with a stable picture. 6 is good at 34 - 36. All the UHF channels are a little stronger now as well. I didn't find any new channels but I wasn't expecting to. Thanks to everyone for the advice.

TV Fool Report

Quote:
Originally Posted by Dave Loudin View Post

Hey, Ken.F, if you want to consider G-H's further, be sure to bookmark this site. Design parameters were run through an optimizer to get around 14dBi gain in the UHF band and 9dBi in the hi-VHF band.

Thanks!
post #14444 of 15407
Ken.F,
Glad the ANT751 worked for you, including lowband VHF channel 6. Thanks for posting back.

Channel 9 is fairly strong at your location. The antenna is just picking it up from the back side of the antenna.

If your numbers are SNR, you usually consistently need ~16 or higher to maintain a lock. More than that won't make the picture quality any better, but higher numbers do give you more insurance against changes due to weather and atmospheric conditions.
post #14445 of 15407
Quote:
Originally Posted by arxaw View Post

Very true.

I think the 751 will work fine for your locals. Do post back with your results, so others may learn from your experience.


RECEIVED MY ANT 751 YESTERDAY, TRIED TV WITH THE FLAT AMPLIFIED ANTENNA I HAD FOR A COMPARISON BEFORE HOOKING UP THE ANT751. WAS PULLING 5 CHANNELS WITH THE OLD ONE, WAS SNOWING A LITTLE OUTSIDE( IF THAT MAKES A DIFFERENCE). HAD 11 CHANNELS WHEN I HAD HOOKED IT UP A WEEK AGO.
HOOKED UP THE ANT751 IN THE ATTIC, POINTED IT IN A GUESTIMATE 250-260 DEGREES , CAME DOWN AND DID A SCAN, PICKED UP 25 CHANNELS, INCLUDEING WTNH 8.1, WHICH IS APPROX 45 MILES AWAY, ACCORDING TO THE CHART. I'M VERY HAPPY, i HAVEN'T FINE TUNED ANYTHING OR TRIED ROTATING IT AT ALL. I WAS GOING TO INITIALLY PUT IT OUTSIDE WHEN I GOT IT, THE SNOW STOPPED THAT THIS MORNING,
THANKS FOR ALL THE ADVICE ARXAW AND CT DISH, HOPE THIS HELPS SOME OTHERS OUT THERE. I MAY BUY ANOTHER AND AIM IT IN ANOTHER DIRECTION, AND PUT IT ON A AB SWITCH DOWN THE ROAD, BUT FOR NOW I WILL SIT BACK AND ENJOY WHAT I HAVE, THANKS AGAIN FOR THE HELP. GLAD THERE IS A FORUM LIKE THIS FOR THOSE OF US THAT ARE TRYING TO LEARN.
post #14446 of 15407
Glad it worked for you. If you're getting the stations you wanted, I would just leave the antenna in the attic, out of the weather. The antenna, coax and connectors will hold up a lot better out of the weather.
post #14447 of 15407
This is a really interesting thread! I was hoping to get some suggestions on antennas. My TVfool analysis results:
http://www.tvfool.com/?option=com_wr...0b86e8f26ce8ec

I'm currently living in an apartment complex, which means I don't really have any means to mount an outdoor antenna . On the plus side, the area is mostly flat; I'm just far away from most of the transmitters.

In the TVfool report above, I'm really only interested in getting the major networks, down to NBC (7). I saw a couple people had posted success with making a DIY antenna; would they be appropriate for my situation?
post #14448 of 15407
Quote:
Originally Posted by clicq View Post

This is a really interesting thread! I was hoping to get some suggestions on antennas. My TVfool analysis results:
http://www.tvfool.com/?option=com_wr...0b86e8f26ce8ec

I'm currently living in an apartment complex, which means I don't really have any means to mount an outdoor antenna . On the plus side, the area is mostly flat; I'm just far away from most of the transmitters.

In the TVfool report above, I'm really only interested in getting the major networks, down to NBC (7). I saw a couple people had posted success with making a DIY antenna; would they be appropriate for my situation?

The terrain isn't very hard on reception where you are. Have you tried any type of antenna, yet? You might be surprised at how well a simple indoor antenna might do.
post #14449 of 15407
Quote:


In the TVfool report above, I'm really only interested in getting the major networks, down to NBC (7). I saw a couple people had posted success with making a DIY antenna; would they be appropriate for my situation?

Yeah, if you have east facing window or east exterior wall with no metal, the GH0n will work well for you. Much better than the U-tube defect.
http://clients.teksavvy.com/~nickm/g..._5V9_10u0.html
post #14450 of 15407
Thread Starter 
Administrative Question:

Is this topic used much for OTA reception hardware besides antennas? Meaning preamps, splitters, combiners, cable, baluns/transformers, mounting hardware, etc?

I ask because in pruning the 'stuck' topics, there was one titled "Antennas, rotators, boosters/preamps... for wide-band VHF/UHF", found here: http://www.avsforum.com/avs-vb/showthread.php?t=546066

It went unused for 6 months, so I closed it, but still left it in the stuck 'Links' topic, because there is a ton of reference material.

I'm considering reopening it and renaming it for all non-antenna reception hardware.

Or should I leave it closed and re-title this topic to add all OTA reception hardware?

Or other?

Thanks in advance for your input.
post #14451 of 15407
I always thought the two threads were redundant and could easily be combined into one.
post #14452 of 15407
Quote:
Originally Posted by difuse View Post

The terrain isn't very hard on reception where you are. Have you tried any type of antenna, yet? You might be surprised at how well a simple indoor antenna might do.

I have not; I guess that's the first thing I should try. I'll grab a basic one from Walmart/Target tomorrow and see how it does.

Quote:
Originally Posted by 300ohm View Post

Yeah, if you have east facing window or east exterior wall with no metal, the GH0n will work well for you. Much better than the U-tube defect.
http://clients.teksavvy.com/~nickm/g..._5V9_10u0.html

Sadly I'm in the middle of the building, with only a north facing window .
post #14453 of 15407
Quote:
Originally Posted by arxaw View Post

I always thought the two threads were redundant and could easily be combined into one.

Same here. The now-locked thread does have a lot of useful information in it, so it would be worth keeping a link to it somewhere for reference. I think it would be confusing to have separate threads for antennas and for antenna-related hardware.
post #14454 of 15407
Thread Starter 
Quote:
Originally Posted by jtbell View Post

Same here. The now-locked thread does have a lot of useful information in it, so it would be worth keeping a link to it somewhere for reference. I think it would be confusing to have separate threads for antennas and for antenna-related hardware.

Ok, two votes for merging, thanks for the feedback.
post #14455 of 15407
Perhaps a title of: Over The Air Antennas and Related Hardware (?)
post #14456 of 15407
Quote:
Originally Posted by clicq View Post

I have not; I guess that's the first thing I should try. I'll grab a basic one from Walmart/Target tomorrow and see how it does.

If you have a RadioShack, this specific model (15-1874) antenna often works much better than other antennas that look almost identical. http://www.radioshack.com/product/in...ductId=2103077
You can return it if it doesn't work.


Quote:
Sadly I'm in the middle of the building, with only a north facing window .

Since you don't have any windows facing the ideal direction, indoor reception may be doable, but may also require patience and a lot of trial and error until you find a reception hot spot, free of interference. Connect a longer piece of coax to the antenna, with a barrel splice. Try different spots in the room, if necessary. High, low, near different walls and possibly in another room. Near a window may be best, but is not always the case with unpredictable indoor reception. You will need to rescan or select "add digital channels" from the TV's channel setup menu, after each time you move the antenna around. If your TV has a signal strength meter, bring that up on the screen to help find a good spot to set the antenna.


.
post #14457 of 15407
Glad I found this thread. Decided to cut cable and save over $100 a month. On a whim I built a antenna (this one) without a reflector. I can pull in all of the major networks plus, ION is spotty.

From TV Fool it looks like I'm in the middle of two banks of towers, the antenna is pointing toward the majors, the ION tower is the opposite direction. My questions. Would adding a reflector help or would a second antenna pointed the other way work (can you combined the two, if so how). These will eventually be installed in a third floor attic space.

Finally because of the length of cable run, over 60 feet, I've added an amplifier to the line (this one) I didn't really notice much of a change in reception. Do these really help.

Thanks. Sorry for all the questions.

post #14458 of 15407
Sorry about that. I added one to my post.
post #14459 of 15407
Adding a reflector will make the antenna more directional, which may help with problem channels (in the direction it's aimed), at the expense of channels the antenna is not aimed directly at. A preamp should not help with the channels in green, and may actually degrade signal quality, due to overload (if it ain't broke...).

Do you currently get any channels to the West?
post #14460 of 15407
Quote:
Originally Posted by arxaw View Post

Do you currently get any channels to the West?

The only one to the west I receive is 30.1, it comes in great. 47.1 rarely comes in and usually only for a few seconds.
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