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Tamerlane
27-Apr-2012, 6:34 AM
Hi there, I am in Toronto desperately trying to get WNED (43.1) from Grand Island near Buffalo, about 50 miles away. Here is my TV Fool report: http://www.tvfool.com/?option=com_wrapper&Itemid=29&q=id%3d0b86425443283e.

I get all local stations but very limited reception from Buffalo. I have tested the following antennas in various directions: with a DB2 I get no Buffalo stations, with a CS2 I get 23.1 marginally, while a DB4e gets 23.1 and sometimes 26.1 and 7.1.

I suspect the problem is interference from some trees and part of a building obstructing my line of sight to Grand Island (if my photo appears below, Grand Island is to the left of the CN Tower in the middle of the photo, partly obstructed by the neighbor's roof). I don't know if adjacent channel interference is possible from a strong local CITYTV 44.1.

Since I am capable of WNLO from Grand Island, as well as WNYB from Jamestown and WKBW from Colden, both even further away, shouldn't I be able to get WNED (and Fox) somehow somewhere? I am guessing a reception breakthrough is unlikely with another of the same type of antenna, but I wonder about a strong directional antenna? Unfortunately I can't manage one of these 6'+ long yagis but if there is a more compact one worth recommending?

Electron
27-Apr-2012, 8:13 AM
Have any of the antennas been mounted above the roof?? Can you mount above the roof?? The window in the picture is what direction?? WNED-DT Real channel 43 PBS is at 162 degree magnetic compass. Here is how to aim antennas , http://www.kyes.com/antenna/pointing/pointing.html. I recommend a Winegard HD9095P or Antennas direct 91XG antenna aimed at about 162 degree magnetic compass mounted above the roof with a good shot through the trees. Yes I know you said no 6 foot antennas , The HD9095P or 91XG have the gain that is needed for reception. You can call or E-Mail Antennas Direct and ask about the correct way to stack 2 DB4e antennas. Do not use a antenna amplifier with any of the antennas.

signals unlimited
27-Apr-2012, 1:35 PM
Stacking two antennas will rarely establish reception of a channel that won't come in with one of the same. Your problem could be resolved (provided you have addressed the mounting and aiming issues mentioned by Electron) by adding an amplifier. The problem is that the strong channels in your report will over load the amp.

Here is an "outside the box" one antenna solution that should work:

Use a Blonder Tongue CMA-BB. This is a UHF/VHF antenna with seperate un-amplified output.

You could run another coax from that and a A/B switch to go from amplified to un-amplified.

Let me know if you want to try this fix and I will find a supplier of that product.

signals unlimited
27-Apr-2012, 1:58 PM
The amplifier is available at sales@prosecuritys.com for $202. That is a little expensive, for an amplifier, but it would make a great improvment in your long range reception without killing your short range reception.

Tower Guy
27-Apr-2012, 2:21 PM
shouldn't I be able to get WNED (and Fox) somehow somewhere?

To get WNED you'll need to attenuate channel 44 without bothering channel 43. To do so, I'd mount a pair of 91XG antennas 56" apart horizontally, and place channel 44 in the first null.

This explains the concept.
http://www.hdtvprimer.com/ANTENNAS/ganging.html

To get FOX try a channel 14 bandpass filter, or a 500 MHz low pass filter, and no preamp

Electron
27-Apr-2012, 4:23 PM
Type , cma-bb and ps-1526 in the , http://www.solidsignal.com , in the solidsignal search box. Can also contact http://www.tinlee.com , about a UHF channel 43 band pass filter , passes 43 and attenuates the other channels.

signals unlimited
27-Apr-2012, 5:20 PM
The bandpass filter could help and is a cheap fix worth trying. If that fails you can use the Blonder Tongue amplifier solution. That would give you the advantage of 21db amplification where you need it, and no amplification where it would be harmfull.

signals unlimited
27-Apr-2012, 8:08 PM
It just dawned on me....Install a good two way splitter/combinder at the antenna. Run the antenna output into the splitter input. hook up any pre-amplifier to one of the splitter outputs, run to the power supply and to an A/B switch. Run a seperate coax from the other splitter output to the A/B and use the A/B to switch from amplified to un amplified. A simple and affordable fix!

Electron
27-Apr-2012, 10:05 PM
Connect the coax from the antenna to the input of a 2 way splitter. Connect the Blonder Tongue channel 43 preamplifier to one of the splitter outputs and then a coax from the preamp to one of the inputs of a Radio Shack # 15-1968 remote control A/B switch. The other output of the 2 way splitter will have a coax that goes to the other input of the A/B switch. And the output of the A/B switch is connected to the Tv.

Tamerlane
27-Apr-2012, 10:41 PM
I really appreciate the responses, thank you! I should have said more about my installation. I do not have roof access at this point in time. The picture attached is from a deck where I can mount and where I've been testing antennas, including with a 15' pole. This is probably my max height which would put the antenna ~10' above the height the photo was taken. My cable is under 30' directly into a Panasonic TV with a decent tuner (no splitting). I am wondering then if amplification is even needed in my case?

For antenna positioning, I have been using the TV Fool bearing information as well as Google Earth. My line to Grand Island goes slightly over/through the neighbor's roof in the photo. I test off directions as well in case signals are bouncing around.

The solutions suggested, in addition to amplification, include yagi antennas and attenuating channel 44. Will the directional antenna will still give me a shot at 43 even if I cannot get above the trees or even above the roof next door? Is there any chance a smaller directional antenna like a RCA ANT751R or something between it and the mega-yagis can pull this off? And should my first step be yagi or attenuation (I can't do two yagis but maybe a trap or bandpass filter idea)?

In other words I just don't know which is the primary obstacle now, the tree+ interference or the adjacent channel. Keep in mind I already get one Grand Island station and one or two further away with the DB4e, but I cannot get two other Grand Island stations (only one of which probably has adjacent channel interference)!??!

Electron
28-Apr-2012, 2:24 AM
The Primary Obstacle is the Trees And Roof/s. The DB4e Must Have a better look at UHF channel 43. Here are some antenna mounts that will get the DB4e Up Higher. http://www.ronard.com/34424560.html , http://www.ronard.com/ychim.html. Get the DB4e with no amplifier HIGHER then roofs and get a good clear shot through the trees and UHF 43 will most likely be received.

Tamerlane
28-Apr-2012, 7:24 PM
Thanks, Electron. I may need to find a way to get that kind of height. I will work on it.

If the trees are the main issue, can you tell me is a directional antenna significantly better at dealing with the issue if I cannot get that kind of height?

Electron
28-Apr-2012, 7:54 PM
The DB4e is a directional antenna and is excellent for reception of UHF Tv channels. A step up is , CM4228HD , HD9095P , 91XG , HD7698P. And stacking antennas. However for your reception situation I suspect that if the DB4e is not receiving the channel then the other antennas will not. You can try the Blonder Tongue preamplifier. Or get a Channel 43 band pass filter from Tinlee and a CPA-19 preamp from Antennas Direct. However the main situation at your location is the trees and roofs. You can cut tree branches away and make BIG hole for the signal to get to the antenna. Also using a Tree Mount , a antenna can be mounted on a tree on the Other Side Of The Trees so the trees are not reducing reception , the DB4e and HD9095P both mount at the back of the antenna so will work better with a tree mount. http://www.ronard.com/tree_adjust.html. Buy ronard mounts at solidsignal by typing the word ronard in the solidsignal search box or buy from ronard. http://www.solidsignal.com

Tamerlane
28-Apr-2012, 8:14 PM
Thanks again. If a more directional antenna is unlikely to do the trick without more height then I guess my next step will be to look into costs of a filter from Tinlee.

Unfortunately the city (and my wife) would have significant problems with my tree trimming (at that height)...

signals unlimited
28-Apr-2012, 9:16 PM
If you are aimed in the right direction, an amplifier could take care of channel 43. I would try one if possible. A Wingard 8700 or any U/V preamplifier that you can get your hands on for the test. If that resolves the channel 43 problem you can go into the recomended more sofisticated configuration to protect your near by channels.

No static at all
28-Apr-2012, 10:06 PM
Am I missing something????????? With 10+ stations less than 3 miles away, in the same direction as the desired weak station, how will an amplifier help??? It would be like using gasoline as starting fluid on a charcoal grill (ouch) In an urban environment such as this one, an amplifier will only worsen the situation. The OP will need to reply on pure antenna gain for any chance of receiving the weak RF43 signal.

I recommend the 91 XG (http://www.amazon.com/Antennas-Direct-91XG-Uni-directional-Antenna/dp/B000LZ9EXI/ref=sr_1_1?s=electronics&ie=UTF8&qid=1335647119&sr=1-1) for it's flexibilty. I would first try it without the extension, which makes it a 43 XG (http://www.amazon.com/Antennas-Direct-43XG-Uni-Directional-Antenna/dp/B000VB6VWE)& see if the smaller footprint will provide the needed gain first. If not, the the extension can be added for additional gain & directivity.

signals unlimited
28-Apr-2012, 10:45 PM
Yes you are missing something...We have recomended a method of using an amplifier for weaker stations in the same path as the near by stations by switching between an amplified line and a clean line established at the antenna using an A/B switch at the set.

Read the previous post.

GroundUrMast
28-Apr-2012, 11:07 PM
@NSA, I don't think you've missed anything, certainly not the obvious. Co-channel interference and the multitude of other strong local signals is the obvious issue. WNED is predicted to have a NM of +32.2 via a line of sight path. That number means that on paper, there is over 1000 times more signal power available than needed to get a lock if not for the overpowering local signals.

I have to disagree rather strongly with any suggestion of using any amplifier or preamplifier. With over a dozen transmitters less than 3 miles from the OP's location, I'd expect the best high-input amplifiers to overload. The AP8700 will be hopelessly overloaded.

If I were going to go to any length to receive WNED, I would try the 91XG first. Next I would try a horizontal stack of identical antennas, adjusted to null out reception of the signal from CITY-DT on real CH-44. If needed, I'd then look into a single channel filter tuned to CH-43. There is more than enough signal and antenna gain to drive any passive filter... I'd expect no more than 3 to 6 dB insertion loss through a good filter, but there's enough power there to drive a filter with over 20 DB insertion loss. (Sadly, the limitation of antenna length may force the OP to try shorter Yagi style UHF antennas if they are willing to attempt to stack. http://forum.tvfool.com/showthread.php?t=1024 The Winegard HD9075 is about 5' long. The Antennas Direct 42XG and SR15 are also less than six feet in length.)

Rule of thumb: "Antenna gain is always better than amplifier gain." (Unless you make you living selling amplifiers.)

GroundUrMast
28-Apr-2012, 11:30 PM
I have to agree that stacking for gain will rarely make a weak signal reliable when the lone antenna can not produce enough signal to get an unreliable lock. This type of stacking rarely produces more than 2 dB additional gain.

However, the goal of stacking in this case is not to increase the gain in the direction of WNED, though that may happen. Instead, the goal is to reduce the reception of the co-channel interference ie. CITY-DT on real CH-44.

Tuning a null of 10 to 20 dB is doable with consumer grade equipment. This is roughly the amount of attenuation needed in this case.

signals unlimited
29-Apr-2012, 12:08 AM
I only recomended the amplifier to be tried to see if It would improve channel 43. Adjecent channel not withstanding it could work....worth a quick try on the deck. If it should happen to work, I recomended that two coax be run from the antenna. One clean(un-amplified) one amplified. Then the use of an a/b switch would select between the lines as needed. No amplification could or should be used on the nearby stations. No amplifier at all if the test amplification fails to produce, and I admit that it could. Just a test....nothing all that stupid.

Tamerlane
30-Apr-2012, 6:54 AM
I am open to all the suggestions here, but for my next step I think I will try a yagi, probably the 91XG, and then a channel filter.

On the antenna question, I didn't realize the 91XG without extension was more or less a 43XG. This flexibility would indeed be handy in my situation. No Static (or anyone), can you tell me whether installing the 91XG without extension, using factory mount, results in an L-shaped antenna or would there still a 'tail' behind the mast?

I read that the retail 43XG installed on a pole is L-shaped, like say the Winegard HD9075P (which also could help in my case).

GroundUrMast
30-Apr-2012, 7:06 AM
Just double checked my 91XG... With or without the front section installed, there will be antenna boom and elements both in front and behind the mast.

Rather than an "L" you will have a "T" shape with the antenna mounted on a mast.

The 42XG is going to be different, more like an "L" arrangement. http://www.antennasdirect.com/cmss_files/attachmentlibrary/Assembly/42XG_Assembly_Instructions.pdf

Tamerlane
30-Apr-2012, 8:01 PM
Thank you for checking that. The 'T' shape on the longish yagis unfortunately adds another challenge to my installation.

Would it be a major compromise to my particular objectives to get an L-shaped yagi, such as the HD9075 you mentioned, or the 43XG (if it is in fact L-shaped)? An online user review of the retail 43XG claims: "The factory mounting has this antenna sticking out from the mast its entire length of 4ft like an upside down 'L'."

GroundUrMast
30-Apr-2012, 9:38 PM
As others have already observed, your problem is not a lack of signal power from WNED. If not for the powerful local signals, you would be receiving signals from Buffalo with little difficulty.

Does the information provided by Tower Guy and this thread, http://forum.tvfool.com/showthread.php?t=1024 make sense to you? Or is the information overly technical?

The shorter antennas can be used to make a tuned antenna array, but you alone can judge your skills and ability to succeed at such a construction project.

Tamerlane
5-May-2012, 6:32 PM
I have been investigating some of the options discussed and I inquired about filter/trap options with a local shop that was suggested here. I was quoted $250.

Is this typical for what I am looking for -- an application that can reduce/suppress the signal from channel 44 without affecting channel 43? I am hoping there is a more affordable option out there.

GroundUrMast
6-May-2012, 4:37 AM
Unfortunately there are few sources for filters of this type. You are looking for a product that is 'custom' in nature and of interest to a small audience. Considering that the test equipment needed to do the final tuning would cost you or I, tens of thousands of dollars, $250 is not at all unexpected.

Tamerlane
7-May-2012, 6:29 AM
Thanks. Let's say I only cared about receiving channel 43 and was not picky about attenuating more than just channel 44, is there any way an off-the-shelf variable trap like the Winegard UT-2700 could work in my situation?

http://www.winegard.com/offair/traps.php

GroundUrMast
7-May-2012, 7:17 AM
If properly tuned, the UT-2700 is a potential competitor of the tinlee.com filter. However, per Winegard, it effects four channels above and below the channel it's tuned to.

However, before buying a filter and the test gear needed to tune it, consider that 'adjacent channel interference' is a bit of a misnomer. A properly tuned, legally operating transmitter is not perfect. It does not transmit 100% of it's RF in the assigned frequency range. Government regulations accommodate the reality that a very small amount of RF will be generated at frequencies outside the channel boundaries. When signals from two transmitters are nearly equal in strength at a receiving location, the very low levels of 'off-channel' emissions may be tolerated by a receiver. But when one signal source is very strong relative to another on an adjacent channel, the strength of 'off-channel' emissions is great enough to interfere with the weaker signal. (It would be cumbersome to to say, "On channel interference generated by an adjacent channel transmitter". But that would be a better description of the problem.)

In your case there is a 30 dB (1000:1 power difference) between the CITY, real CH-44 signal and the WNED, real CH-43 signal. Therefor the 'off-channel' emissions from CITY are 1000 times more significant as a source of interference to the WNED signal.

A perfect filter tuned to CH-44 will control the 'on-channel' signal from CITY but will still pass real CH-43 frequencies, including those generated by sources other than the WNED transmitter.

Your best hope for reception of WNED is to build, tune/adjust an antenna that has little sensitivity in the direction of CITY while having optimum sensitivity in the direction of WNED. A quality bandpass filter tuned to CH-43 may help, but I doubt a filter by itself will provide a reliable reception solution. Success lies in maximizing reception of the RF radiated from WNED while minimizing reception of the RF from CITY, including both the on-channel and off-channel emissions.

So, how would you answer the question posed in post 24 of this thread?

Tamerlane
10-May-2012, 7:16 PM
So, how would you answer the question posed in post 24 of this thread?

Thanks again for all the helpful responses. To answer your question, I have been making my way through the links on stacking / ganging. Some of the technical discussion is over my head but the practical technique does not seem prohibitively difficult to experiment with.

I was of course initially drawn to the idea of a better antenna and/or filter in the hopes these would be cheaper, simpler and more acceptable to the aesthetic demands of other people affected given the constraints of my deck installation.