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The Official AVS Antenna and Related Hardware Topic! - Page 513

post #15361 of 16087
Nice. cool.gif
post #15362 of 16087
I have 3 set top boxes with uVerse. Don't they burn alot of power? What is a good way to avoid that other than unplugging them all?
post #15363 of 16087
Quote:
Originally Posted by dinosaur1 View Post

I have 3 set top boxes with uVerse. Don't they burn alot of power? What is a good way to avoid that other than unplugging them all?
Leave them alone. They use about a penny a hour, just doing nothing, even when watching tv, they use around 2 cents a hour.
post #15364 of 16087
So I cut the cable today with dtv and I am thinking of going OTA. I am up in the foothills of the Sierra Nevada mountain range north of Fresno, CA

"First, you should enter your location into www.tvfool.com (both "Click Here" to see predictions and "Start Here" to see an individual station colorized coverage map and post the RESULTS URL (webaddress at top of browser) so we can see it."

So any thoughts:

http://www.tvfool.com/?option=com_wrapper&Itemid=29&q=id%3d1ddaf65a208286

I think it will be the roll of the dice to see if I can pick up any OTA from Fresno with a roof mounted UHF
post #15365 of 16087
post #15366 of 16087

Why the heck would they recommend that thing? You don't have any receivable low-VHF stations in range.
post #15367 of 16087
[quote name="Johnnycanal" url="/t/381623/the-official-avs-antenna-and-related-hardware-topic/15360#post_23211582"
I think it will be the roll of the dice to see if I can pick up any OTA from Fresno with a roof mounted UHF[/quote]

I have a similar prediction (many more in the yellow, though.) With something like a Winegard HD7696P in the attic, I can pull in anything in the yellow. The channels in the red are hit or miss, mainly miss. Going outside with an antenna the size of a Winegard HD7698P will help, but I can't guarantee that you'll get reliable reception.
post #15368 of 16087
Quote:
Originally Posted by Johnnycanal View Post

So I cut the cable today with dtv and I am thinking of going OTA. I am up in the foothills of the Sierra Nevada mountain range north of Fresno, CA

"First, you should enter your location into www.tvfool.com (both "Click Here" to see predictions and "Start Here" to see an individual station colorized coverage map and post the RESULTS URL (webaddress at top of browser) so we can see it."

So any thoughts:

http://www.tvfool.com/?option=com_wrapper&Itemid=29&q=id%3d1ddaf65a208286

I think it will be the roll of the dice to see if I can pick up any OTA from Fresno with a roof mounted UHF

I live in the Sierra foothills about 60 miles northwest of you. I know the problems people in this area face with OTA. I can receive all the stations in my TVFool report down to KICU 36 with a noise margin of -13.8 dB except for a few low power stations shown but not on the air.

http://www.tvfool.com/?option=com_wrapper&Itemid=29&q=id%3dcc49e65f5d3c18

But..... I'm using the antennas shown in my avatar which are 70' high. This height is required to clear all the local ground clutter, especially trees. If the proposed location for your antenna has trees right in front of it you can forget UHF. If it's clear for 1/2 mile of more before encountering any trees then it might work. Trees are less of a problem for high VHF.

Also the angle to the first edge down the path that the signals have to refract over is important. My first edge is 2350' away and the angle is 0.8 degrees. The greater the angle the more the attenuation.

Another major issue up here is multipath. A lot of us have a problem with higher mountains behind our antennas with a better path to the transmitters reflecting strong signals and causing multipath. I don't know if that applies to you or not.

I've found that TVFool often under predicts the signal strength for non LOS signals which is to my advantage. I performed an analysis on my local stations and a few not so local stations to see how TVFool performed in regards to predicted Noise Margin. I've attached that table. Look at the last column which takes into account all my parameters. Positive means better than predicted and negative means worse than predicted. The last two stations are my only LOS stations.

For you I'd recommend a 91XG for UHF and a YA-1713 for VHF (KAIL), or better yet a single channel yagi for KAIL assuming KNSO is not a priority.

post #15369 of 16087
Quote:
Originally Posted by gcd0865 View Post

Jay:

Calaveras is right about channel 11.1, which is on RF10. You're using a UHF-only antenna (albeit a very good one), which won't resonate well at VHF-high frequencies. Cheapest/quickest solution is to add a Y5-7-13 VHF-high antenna a foot or two below your DB8 on the same mast, and join it with your DB8 using two short (3-4-foot) RG-6 coax pieces fed into a UVSJ up at the mast, with a single RG-6 coax fed down from there to your tv. Also, as Calaveras said, if you're using any kind of distribution amp to split your signal to multiple tv's, take it out and replace it with a simple splitter, since you're too close to your transmitters for any amplification.

http://www.solidsignal.com/pview.asp?p=y5-7-13
http://www.solidsignal.com/pview.asp?p=uvsj

With at least one VHF-high station in your area, the DB8 wasn't really the right choice for you, even though it's a very good UHF antenna. It's way more powerful than you need at such close range, and UHF-only. Presuming that it can't be returned since it's been outside, if you wanted to sell it to someone who needs a longer-range UHF antenna, you could switch to the RCA ANT751 or Winegard HD1080, both of which cover both UHF and VHF-high, in a smaller size.

http://www.solidsignal.com/pview.asp?mc=03&p=ANT751
http://www.solidsignal.com/pview.asp?p=HD-1080

Thank you all very much for your feedback - very useful and I am almost there. I bought the Winegard HD1080, installed it an bingo - I now get the missing Atlanta VHF channels. However, I suffer pixilation on a couple channels still and wanted some more of your valuable feedback. As background, I have moved the antenna 180 degrees and monitored channel signal strength through the TV box. What seems to be happening on a few channels is the a fluxuation of the signal. Perfect and strong then black and that cycles back and forth.Is that modern day multi-path problems?

Is there a proper way to aim this particular antenna. It's a rectangle configuration and I assumed the from was the flat portion and thats what I aim at about 190 degrees where most of the transmitters are located? After moving it around, I found that I get the best reception with the side in the direction. Doesn't seem logical but that's why I am asking.

Would it be helpful to provide the channel ID's of those giving me problems?

Is there any other info you think I could provide that might help?

thanks again for all your assistance.

Jay
post #15370 of 16087
Thanks

The "91XG for UHF" seems like a much better choice than the HD8200U. I think I'll pass on the HD7698P as VHF isn't an issue.

I think I can get a bit off the rooftop without too much problem, but a 70' tower will not meet the WAF... eek.gif I'll climb up there this weekend with compass and binoculars and take a look.
post #15371 of 16087
Quote:
Originally Posted by jaygroundw View Post

Thank you all very much for your feedback - very useful and I am almost there. I bought the Winegard HD1080, installed it an bingo - I now get the missing Atlanta VHF channels. However, I suffer pixilation on a couple channels still and wanted some more of your valuable feedback. As background, I have moved the antenna 180 degrees and monitored channel signal strength through the TV box. What seems to be happening on a few channels is the a fluxuation of the signal. Perfect and strong then black and that cycles back and forth.Is that modern day multi-path problems?

Is there a proper way to aim this particular antenna. It's a rectangle configuration and I assumed the from was the flat portion and thats what I aim at about 190 degrees where most of the transmitters are located? After moving it around, I found that I get the best reception with the side in the direction. Doesn't seem logical but that's why I am asking.

Would it be helpful to provide the channel ID's of those giving me problems?

Is there any other info you think I could provide that might help?

thanks again for all your assistance.

Jay

Sounds like what you're describing could be airplane flutter (multipath). It goes like this: Stable signal and then it pixelates or drops out completely. It may go in and out and then settles back down for some time. Most of the time signal is okay. This is difficult to do much about.

If the signal constantly pixelates/drops out and seldom settles down then it could be moving vegetation caused by wind disrupting the signal. Moving the antenna to a different spot may help this.

If the signal pixelates and then drops out for an extended period of time then it's more likely to be temperature inversion issues that lower the signal strength below the digital cliff. A better/higher antenna may help this.

Here's a link to a spectrum analyzer animation I made showing what's happening during airplane multipath. This is KGO on channel 7 when it is weak. It is unstable then goes into what looks like an oscillation. That's the airplane reflection adding/subtracting from the ground signal and changes as the airplane moves. Notice the next signal up on channel 8 is stable. Ignore the digital public service channel on 173.3 MHz that's bouncing up and down.

http://images.aa6g.org/AVSForums/KGO-Animation-3.gif
Edited by Calaveras - 4/17/13 at 10:27am
post #15372 of 16087
Quote:
Originally Posted by Johnnycanal View Post

Thanks

The "91XG for UHF" seems like a much better choice than the HD8200U. I think I'll pass on the HD7698P as VHF isn't an issue.

I think I can get a bit off the rooftop without too much problem, but a 70' tower will not meet the WAF... eek.gif I'll climb up there this weekend with compass and binoculars and take a look.

The 91XG has the best pattern of any UHF antenna I know of and hence does the best job rejecting multipath signals. I've heard reports from up here that that is the only antenna some foothill residents have had success with. That's certainly true fro me.

The height of the antenna required to receive what you want will be determined by your tree/horizon situation. There are no magic antennas and the WAF is irrelevant except to decide whether you'll have to return to satellite/cable. Of course the minimum height might be impractical under any circumstances. My minimum useful height is about 60' and I was able to get them up to 70'. 120' would clear my closest edge but that is too expensive and impractical for other reasons.
post #15373 of 16087
Hi, I'm new in the forum. i hope that this reply finds the guy in Winlock WA. I live close by, on a hill in Chehalis WA and I've been using the 91xg, trying to improve my reception, thinking of going to two stacked. Would like to come by and visit you, get ideas and advice. is that possible?
post #15374 of 16087
Quote:
Originally Posted by Purplepig60 View Post

Hi, I'm new in the forum. i hope that this reply finds the guy in Winlock WA. I live close by, on a hill in Chehalis WA and I've been using the 91xg, trying to improve my reception, thinking of going to two stacked. Would like to come by and visit you, get ideas and advice. is that possible?

If you can find one of his posts you can send him a private message.
post #15375 of 16087
Hey guys. This is not an antenna related problem, but I am not sure where to go... I am having an issue with a local LD TV broadcaster who is affiliated with the THIS TV network. There is no CC provided through his LD channel, but I have confirmed through a local full power broadcaster 75 miles away that CC was being provided through the network... Thr local LD owner claims that to provide CC would be cost prohibitive... I say it just needs to be configured to pass through the network provided CC... Where can I go to find out more about this. Thanks for indulging me...
Edited by OTAhead - 4/30/13 at 4:59am
post #15376 of 16087
Quote:
Originally Posted by OTAhead View Post

Where can I go to find out more about this.
The FCC website.
post #15377 of 16087
Hello all!

I've been looking through this site for a couple of weeks now. I must say I'm quite impressed with the wealth of knowledge and helpfulness and politeness of the members here. I read back a year in this thread alone. In addition, there are reference links offered to other posts which in turn lead to further research. I thought I was never going to get through everything, but I now have a better understanding of the terminology and believe I am ready to get some advice.

Like others, I came here with the intent of doing away with cable for obvious reasons. Of course, who wouldn't mind an attic install under the right conditions, but I'm going with a roof mounted unit. With that said, here is my TV Fool report based on my exact coordinates and a 25' height.


http://www.tvfool.com/?option=com_wrapper&Itemid=29&q=id%3d1ddafef280218c


I played with a +/- 5' height variance and didn't notice much of a change, but I'm no expert at deciphering all of the given information. With the exception of WSKY-TV (RC 9) at over 44 miles away, all of the stations I'm after are LOS. At 30', it would also become LOS. This is a station I wouldn't mind receiving. It is one of three VHF channels over a 13 degree angular spread (RC 7 and 13 are the others).

So based on my reading, I've seen two or three antennas recommended over the last year by various folks on the forum. Looking at other reports similar to mine, I'm guessing I may need the good old RCA ANT751R.

Regarding mast material: If the antenna mast were made out of a non conductive material, there wouldn't be a need to ground it, only the antenna itself via a grounding block. Maybe I missed it somewhere, but there must be a reason why masts aren't constructed with non conductive materials. Just curious...


Thanks much in advance for the help!! smile.gif

Bob
post #15378 of 16087
Only thing about using Schedule 40 or 80, instead of a steel mast pipe, is that you need to make sure that it is uv resistant. I would put in a piece of pressure treated inside, to help support, or slip in emt, and still ground the antenna & mount.

With your range, probably could go with the same setup I have. I am using the Antennas Direct DB8 for UHF, and the Antennacraft® Y5713 60" Cut-to-Band HDTV Antenna, with a UHF/VHF Splitter/Combiner between the two, and the Channel Master 7778 Pre-amp. Even on a night like tonight with rain storms, I am still getting 80's for our PBS station that is around 12 miles away, the opposite direction that the face of the antenna is, and in the mid to high 80's for our CW station at around 50 miles away.

It took me some tweaking, which I actually ended up using a Winegard RFL-342 SensarPro Signal strength meter that I put in a kit box, and powered with a 12vDC 500mA to get the best signal. Worked out better than the signal meter on our Panny Plasma, and got it dialed in really great at the best signal.
post #15379 of 16087
ANT751 without a Preamp should work just fine in your location.

Metal Masts are used for a few important reasons:

1. It's lighter, stronger, longer lasting, survives severe weather, usually lower cost and requires no periodic maintenance like wood, PVC or fiberglass.

2. When wind passes over an antenna, a static charge builds up (like shuffling your feet over carpet). Unfortunately, SOME Balun Transformers (nearly ALL INDOOR Baluns and even some OUTDOOR Baluns) do NOT have a Direct Current path between the 300-ohm leads and the 75-ohm shield wires, so this static charge CAN NOT be dissipated, which can in turn ATTRACT lightning. Also, when the static electricity voltage exceeds the breakdown voltage between the 300-ohm windings and the 75-ohm windings, it will end up being momentarily (and periodically) applied to your equipment as it is dissipated across the "Ground Block" spark-gap device (mandatory NEC requirement when coax enters the structure). Hence the need to ground the antenna mast which is nearly always connected to at least some part of the antenna.

3. If you DO use an OUTDOOR Balun Transformer that has a Direct Current path between the windings (e.g. Channel Master, RCA VH101N and a few others), the situation is a bit better, since static electricity is being CONSTANTLY drained to ground via the coax shield. HOWEVER, in the rare event of a direct lightning strike, the only path to ground would be along the coax to the Ground Block and thence to actual GROUND that is hopefully a short distance away. Most of the Coax to Ground path will be turned to aluminized vapor that hopefully facilitates directing the lightning OUTSIDE the building, rather than THRU it. However, due to the fragility of the Coax and the proximity to the structure, it isn't a very reliable safety plan, since the coax will break away. When a metal mast is used, the much larger wire size and hopefully shorter path to ground (on the average), greatly reduces the likelihood of severe structure damage.

I MIGHT have a Philips OUTDOOR Balun in my spare parts drawers that I could also test (unless they're all in service)....but I don't even KNOW where THAT spare parts drawer is....had a slab leak that required running new water lines from the heater and a beautiful new LR/DR/KIT floating engineered wood floor to replace the 30+ yo Oak Parquet that was ruined in the DR. Since I had to move all of my papers, storage cabinets & electronics out of the Fam/CPU Rm, it was time to recarpet that room, scrape off popcorn ceilings & paint all of the drywall patches throughout the house. Last 6-wks we've been in upheaval....but fiberglass sheet floors for both Bathrooms should be here soonish...
Edited by holl_ands - 5/3/13 at 7:50pm
post #15380 of 16087
Quote:
Originally Posted by masheen View Post

Regarding mast material: If the antenna mast were made out of a non conductive material, there wouldn't be a need to ground it, only the antenna itself via a grounding block. Maybe I missed it somewhere, but there must be a reason why masts aren't constructed with non conductive materials. Just curious...

I don't think there's any point to using a non-conductive mast because you still have coax running down.

Grounding is to bleed off static build-up and protect against induced currents from nearby lightning strikes. It won't protect your system against a direct strike. If you take a direct strike you'll be replacing everything. My antennas are high up on a tower which is grounded but I disconnect everything when we have a thunderstorm to be extra safe.

I think there is a pretty good chance you'll be able to receive WSKY at 44 miles but you'll likely see more signal variation than with any of the close by stations. You'll probably see no variation on the LOS stations.
post #15381 of 16087
Makes sense to me! I'll definitely go with a standard mount and utilize the proper grounding methods. I decided to try the RCA ANT751R since I can get a pretty good deal on it. I'll certainly report my results once everything is set up.

Sorry to hear about your water leak holl_ands! No fun I'm sure. frown.gif

Thanks for the input guys and giving me a cipher on my TV Fool report Chuck! You all are the reason this site is what it is!! smile.gif
post #15382 of 16087
I live in Lacey, Washington State, which is near the state capitol of Olympia. Here's my TVfool:

http://www.tvfool.com/?option=com_wrapper&Itemid=29&q=id%3d1ddaf78697886d

I'm working with the 91XG antenna for UHF and the Y10-7-13 for VHF. My research indicated these were the best for difficult locations like mine. I'm combining the signals with a UVSJ and feeding through a CM7777 preamp . My cable run is 50 ft. I'm dealing with numerous coniferous and broadleaf trees in the direction of the desired stations.

The stations I really want are PBS (27), Fox (13), ION (33), and CBS (51). I'd like to get ABC and NBC but alas, it is not to be. I'm stacking the VHF antenna above the UHF on the same mast. After moving the mast all over the roof and checking the signal I've identified two locations on the roof when the signals are the strongest. I'll call them location "A" and location "B". Unfortunately each location has a problem. Location A gets a stong signal on the one VHF station (Fox 13) and decent signals on 2 UHF stations but no signal on the PBS station. Location B gets a strong signal on the PBS station and ION, a marginal signal on CBS and no signal on Fox. I can easily see that the best locations correspond to gaps in the trees in the directions of the stations.

My question is: what if I kept the stacked array of VHF and UHF at location A and added another UHF antenna at location B just to get PBS? How would I combine the feed?
post #15383 of 16087
Quote:
Originally Posted by hidesertforester View Post

My question is: what if I kept the stacked array of VHF and UHF at location A and added another UHF antenna at location B just to get PBS? How would I combine the feed?

Use separate feedlines with an A/B switch in the house. You cannot just connect the two antennas together for the channels you want without an elaborate and expensive filter system.

Any chance you could have someone top one of the pine trees and put your antenna on the top? I have have a friend who has done this. Its the only way he can receive UHF from his location.
post #15384 of 16087
Quote:
Originally Posted by Calaveras View Post

Use separate feedlines with an A/B switch in the house. You cannot just connect the two antennas together for the channels you want without an elaborate and expensive filter system.

Any chance you could have someone top one of the pine trees and put your antenna on the top? I have have a friend who has done this. Its the only way he can receive UHF from his location.

Okay, that's what I was afraid of. Putting the antennas up a tree would be an expensive proposition and as a retired professional forester I know that topping a tree always compromises it's long-term health. My objective is just to get my HD channels permanently. I know Comcast is going to eventually encrypt the ones I get in the clear currently.

I'm going to try a compromise solution by separating my antennas, keeping the VHF in it's optimum location and moving the UHF to see if I can get a decent stable reception on the remaining channels. That way I can still feed everything through the CM7777.
post #15385 of 16087
The signals is looking at are pretty strong but they come from different directions. I would be very surprised that any of the UHF stations would be a problem with the antenna aimed at them. Also the preamp may be doing more harm than good in this strong signal situation.
The 91XG has a very sharp beamwidth so a rotator may be in order to receive from multiple directions. TV antennas usually work better with the UHF one above the VHF antenna. A CM4221 would probably be a better antenna to try if you don't want a rotator.
John
post #15386 of 16087
Quote:
Originally Posted by ctdish View Post

The signals is looking at are pretty strong but they come from different directions. I would be very surprised that any of the UHF stations would be a problem with the antenna aimed at them. Also the preamp may be doing more harm than good in this strong signal situation.
The 91XG has a very sharp beamwidth so a rotator may be in order to receive from multiple directions. TV antennas usually work better with the UHF one above the VHF antenna. A CM4221 would probably be a better antenna to try if you don't want a rotator.
John

My local trees are the problem, John. I have no doubt I could get most of the Seattle stations if I didn't have trees in the way. I did try without the preamp. The preamp gets me CBS on 51. Without it I don't get it. I also get ABC with it but with a lot of breakup. I've tried rotating the antennas and it doesn't help. I have to move to a different location on the roof to get through the few gaps in the trees.
post #15387 of 16087
Quote:
Originally Posted by hidesertforester View Post

My local trees are the problem, John. I have no doubt I could get most of the Seattle stations if I didn't have trees in the way. I did try without the preamp. The preamp gets me CBS on 51. Without it I don't get it. I also get ABC with it but with a lot of breakup. I've tried rotating the antennas and it doesn't help. I have to move to a different location on the roof to get through the few gaps in the trees.

A UHF stacked bowtie array will probably get you the signal you want, on UHF. Such an antenna is really good at collecting signals that have bent through trees. The one you are using is quite good when there are no obstructions, but clearly you do have some.
post #15388 of 16087
Quote:
Originally Posted by difuse View Post

A UHF stacked bowtie array will probably get you the signal you want, on UHF. Such an antenna is really good at collecting signals that have bent through trees. The one you are using is quite good when there are no obstructions, but clearly you do have some.

There's no magic to the stacked bowtie compared to the yagi type (91XG) so there's no reason to think it'll perform better. Here's an illustration of what trees do to signals.

http://www.hdtvprimer.com/ANTENNAS/siting.html

The 91XG has the best pattern of any commercial wideband antenna I know of. Rejection of signals from directions other than the main path can sometimes be more important than the gain.
post #15389 of 16087
At my location, I do not have LOS so I probably have non-uniform fields as defined in the hdtvprimer website you cited. When I used an old CM4228 UHF antenna (8 bay), I could not find a sweet spot that gave reliable reception on all the stations I wanted to watch. The ones I could get were about medium quality. I switched to a CM4221 antenna (4 stacked bowties) and I got all the high power channels from Mt. Wilson with high signal quality. My experience may be unique but so far no reception problems, rain, wind or shine.
post #15390 of 16087
Quote:
Originally Posted by Calaveras View Post

There's no magic to the stacked bowtie compared to the yagi type (91XG) so there's no reason to think it'll perform better. Here's an illustration of what trees do to signals.

http://www.hdtvprimer.com/ANTENNAS/siting.html

The 91XG has the best pattern of any commercial wideband antenna I know of. Rejection of signals from directions other than the main path can sometimes be more important than the gain.

I was not suggesting magic.. I would not question that the 91XG does very well when it can "see": a signal.. At the proper height and direction for any given signal it certainly would do better than stacked bowties. But, if there is more than one signal to be received and those signals might be bending some, then the optimized height and direction for one signal might not be effective for others,.

I will fully agree that rejection of unwanted RF is a significant ideal. A yagi type antenna will "reject" much that is outside its narrow reception beam. In the case we are discussing, that antenna might also be rejecting some wanted signal.. If there were a procedure for correcting the height and direction of a very directional antenna for each desired signal, that antenna would be a first choice, If that is not practical, and no one fixed antenna position is satisfactory,. then another solution will be needed.
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