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Can any of you home antenna builders help me on how to build an antenna tuned into UHF-LP 30 (My local 'RetroTV' station is KSMI-LD 30.1-6) as they are now showing classic "DR WHO" and I am currently only receiving a signal strength of 35% while my major networks are in the 95+% range from the same 'broadcast tower farm'.
So I am looking for a 'tuned' antenna that I can add the feed to my current antenna with out the loss of signals on the adjacent channels.
 

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We need more info to narrow the scope of your inquiry. What Antenna are you using now? Indoor? Outdoor? Pointed towards KSMI or another direction to favor some other station? And we need your TVFool Report (enter location and copy/paste the Results URL (webaddress at top of page) into a post so we can see your relative signal strengths.
 

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We need more info to narrow the scope of your inquiry. What Antenna are you using now? Indoor? Outdoor? Pointed towards KSMI or another direction to favor some other station? And we need your TVFool Report (enter location and copy/paste the Results URL (webaddress at top of page) into a post so we can see your relative signal strengths.
I hope that this answers your questions you posed to me.

?: What Antenna are you using now?
A: Radio Shack External/Outdoor Antenna When Purchased in 1995 was rated at 70 miles VHF it is about 6 foot long tip to tip.

?: Pointed towards KSMI or another direction to favor some other station?
A: No "most" of the local stations have their towers in a "Tower Farm" in a little suburb of named 'Colwich, KS' which is where it is pointing.

TV Fool: http://www.tvfool.com/?option=com_wrapper&Itemid=29&q=id=e1c61f0803753f
Note: TV Fool still lists the station with a call number of 50.1-6 when they have changed to match their UHF channel of 30.1-6
http://en.wikipedia.org/wiki/KSMI-LD

If anything the antenna is pointing towards KTPS8.1-4
KPTS-DT (Digital)
Channel: 8 (8.1)
Network: PBS
Maximum ERP: 32.000 kW
Coordinates: 38.055845 -97.776715
Effective ERP: 17.104 kW (Adjusted according to your location)
Distance: 39.2 miles Azimuth: 320 degrees Compass: 317 degrees

Transmitter Profile Detail
KSMI-LP (Digital)
Channel: 30 (30.1)
Network:
Maximum ERP: 15.000 kW
Coordinates: 37.800289 -97.525046
Effective ERP: 15.000 kW (Adjusted according to your location)
Distance: 16.8 miles Azimuth: 318 degrees Compass: 314 degrees

So the difference is only about 2 degrees which is such a small amount when trying to adjust an antenna.
 

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Your TV Fool report shows it should be easy to receive all the LOS stations in your list by pointing the antenna at about 335 degrees. It doesn't get much better than that. If you're having problems with one or more stations I'd check the antenna and cabling. Maybe something happened in the last 19 years. You show your antenna mounted at only 10'. Is it outside on the roof? If not, it needs to be.
 

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Simple question: How big must the wire be to hook up UHF antenna elements?

I am building an indoor UHF antenna and have several elements to my antenna (2 to 14 figure-eight full wave elements). I know I need to hook them together in parallel but how small of a wire can I use?
Since there is very little voltage or current can I use 22 gauge? Or, is 18 gauge needed for some reason? How big of a wire do I need to get all the signal out of my elements?
 

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Feedlines are Transmission Lines which need to have a specific Impedance to prevent SWR problems that degrades both the signal strength AND the digital waveform due to signals reflecting up and down the coax. The Wire Size and Separation between the Feedlines determines this Impedance. If Wire Size is TOO small, there will also be unacceptable (RF) ohmic losses. Typically AWG12 and preferably AWG10 is used for Feedlines at VHF and UHF frequencies.

All "Figure-Eights" in Parallel won't work...Impedance will be way too low, resulting in high SWR. You can't JUST hook up some individual antennas and hope for the best...they have to be carefully laid out in an Array (Vertical, Horizontal...or a mixture) and interconnected with the correct LENGTH of Feedlines, such as is shown for the following COMPUTER OPTIMIZED 8-Bay Bowtie designs:
http://imageevent.com/holl_ands/stacked/verticallystackeduhf/vertstackff4doubleanglerefl
http://imageevent.com/holl_ands/stacked/verticallystackeduhf/vstackm495x9noreflector
http://imageevent.com/holl_ands/multibay/8bayrefl
http://imageevent.com/holl_ands/multibay/8bay

Perhaps you can provide more detailed information on what you're working on.....BTW: I analyzed individual Figure-8 Antennas here:
http://imageevent.com/holl_ands/loops/twinhoopchireix
http://imageevent.com/holl_ands/loops/hivhftwinloops
Note that QICT (Quarter Inch Copper Tubing) Elements provided acceptable SWR, whereas AWG10 did NOT...this is fairly common for Loop Antennas....except the similar Hourglass-Loop designs are fairly insensitive to Element Wire Size.
http://imageevent.com/holl_ands/loops

There are also "Figure-8" Antennas where there is NO interconnection at the crossover point, such as:
http://pa0fri.home.xs4all.nl/Ant/Magloop/magn8.htm
http://www.mixw.co.uk/MagLoop/magloop.htm

Ken Nist has (had?) an EZNEC model for the above "Figure-8" Antenna on his HDTVPrimer website, which I converted into the fol. 4nec2 File. It provides 2.7 to 5.4 dBi Raw Gain with good SWR, EXCEPT below 554 MHz it climbs to an excessive value of 5.5:

Code:
  Freq  RawGain  NetGain    SWR    BeamWidth
=========================================
 470.0    2.683   -0.515   6.191    83.5
 482.0    2.963    0.140   5.479    83.5
 494.0    3.223    0.769   4.831    83.5
 506.0    3.463    1.367   4.245    83.5
 518.0    3.703    1.950   3.720    83.3
 530.0    3.913    2.483   3.252    83.3
 542.0    4.123    2.992   2.837    83.2
 554.0    4.317    3.457   2.471    83.2
 566.0    4.507    3.885   2.151    82.9
 578.0    4.677    4.256   1.873    82.8
 590.0    4.837    4.577   1.635    82.7
 602.0    4.987    4.846   1.435    82.5
 614.0    5.117    5.052   1.277    82.4
 626.0    5.227    5.195   1.185    82.2
 638.0    5.316    5.278   1.207    82.1
 650.0    5.376    5.294   1.317    82.0
 662.0    5.406    5.250   1.464    81.8
 674.0    5.396    5.142   1.627    81.6
 686.0    5.316    4.950   1.796    81.6
 698.0    5.176    4.694   1.959    81.3
 710.0    4.946    4.358   2.106    81.2
 722.0    4.612    3.937   2.222    81.1
 734.0    4.162    3.433   2.296    80.8
 746.0    3.572    2.827   2.317    80.7
 758.0    2.842    2.122   2.284    80.6
 770.0    1.972    1.314   2.199    80.4
 782.0    0.992    0.426   2.075    79.9
 794.0   -0.068   -0.526   1.926    79.1
 806.0   -1.148   -1.497   1.769    78.1
Code:
CM Figure-8 Loop, Ken Nist's EZNEC file converted with 4nec2 on 28-Oct-11 15:21
CE
GW    1    5    -0.217239    -0.563649    3.196611    -0.217239    0.5636488    3.196611    0.04
GW    2    5    -0.217239    0.5636488    3.196611    -0.217239    1.622963    2.8110524    0.04
GW    3    5    -0.2172387    1.62296299    2.81105236    0    2.48652087    2.08644134    0.04
GW    4    5    0    2.48652087    2.08644134    0    3.05017165    1.11016772    0.04
GW    5    5    0    3.05017165    1.11016772    0    3.24592598    -7.9361e-6    0.04
GW    6    5    0    3.24592598    -7.9361e-6    0    3.05012756    -1.1101752    0.04
GW    7    5    0    3.05012756    -1.1101752    0    2.48647992    -2.0864417    0.04
GW    8    5    0    2.48647992    -2.0864417    0    1.62292008    -2.8110535    0.04
GW    9    5    0    1.62292008    -2.8110535    0    0.56364882    -3.1966098    0.04
GW    10    5    0    0.56364882    -3.1966098    0    -0.5636488    -3.1966098    0.04
GW    11    5    0.2172387    -0.563649    3.196611    0.2172387    -1.62296    2.8110524    0.04
GW    12    5    0.2172387    -1.6229602    2.81105236    0    -2.486526    2.08644134    0.04
GW    13    5    0    -2.486526    2.08644134    0    -3.0501752    1.11016772    0.04
GW    14    5    0    -3.0501752    1.11016772    0    -3.2459307    -7.9361e-6    0.04
GW    15    5    0    -3.2459307    -7.9361e-6    0    -3.0501303    -1.1101752    0.04
GW    16    5    0    -3.0501303    -1.1101752    0    -2.4864803    -2.0864417    0.04
GW    17    5    0    -2.4864803    -2.0864417    0    -1.622926    -2.8110535    0.04
GW    18    5    0    -1.622926    -2.8110535    0    -0.5636488    -3.1966098    0.04
GW    19    5    0    -0.5636488    9.58984646    0    0.56364882    9.58984646    0.04
GW    20    5    0    0.56364882    9.58984646    0    1.62296299    9.20428346    0.04
GW    21    5    0    1.62296299    9.20428346    0    2.48652087    8.47967323    0.04
GW    22    5    0    2.48652087    8.47967323    0    3.05017165    7.50339764    0.04
GW    23    5    0    3.05017165    7.50339764    0    3.24592598    6.39322047    0.04
GW    24    5    0    3.24592598    6.39322047    0    3.05012756    5.28305512    0.04
GW    25    5    0    3.05012756    5.28305512    0    2.48647992    4.3067874    0.04
GW    26    5    0    2.48647992    4.3067874    0.2172387    1.62292008    3.58217638    0.04
GW    27    5    0.2172387    1.6229201    3.5821764    0.2172387    0.5636488    3.196611    0.04
GW    28    5    0.2172387    0.5636488    3.196611    0.2172387    -0.563649    3.196611    0.04
GW    29    5    0    -0.5636488    9.58984646    0    -1.6229602    9.20428346    0.04
GW    30    5    0    -1.6229602    9.20428346    0    -2.486526    8.47967323    0.04
GW    31    5    0    -2.486526    8.47967323    0    -3.0501752    7.50339764    0.04
GW    32    5    0    -3.0501752    7.50339764    0    -3.2459307    6.39322047    0.04
GW    33    5    0    -3.2459307    6.39322047    0    -3.0501303    5.28305512    0.04
GW    34    5    0    -3.0501303    5.28305512    0    -2.4864803    4.3067874    0.04
GW    35    5    0    -2.4864803    4.3067874    -0.2172387    -1.622926    3.58217638    0.04
GW    36    5    -0.217239    -1.622926    3.5821764    -0.217239    -0.563649    3.196611    0.04
GS    0    0    0.0254        ' All in inches.
GE    0
GN    -1
LD    5    0    0    0    5.74713e7    0
EX    0    10    3    0    -1    1.22461e-16
'
' FR Freq Sweep choices in order of increasing calculation time (fm holl_ands):
' FR 0 0 0 0 590 0        ' Fixed Freq
FR 0 29 0 0 470 12        ' Freq Sweep 470-806 every 12 MHz - OLD UHF BAND
' FR 0 39 0 0 470 6        ' Freq Sweep 470-698 every 6 MHz - PREFERRED FOR UHF
' FR 0 77 0 0 470 3        ' Freq Sweep 470-698 every 3 MHz
' FR 0 153 0 0 470 1.5        ' Freq Sweep 470-698 every 1.5 MHz
' FR 0 71 0 0 300 10        ' Freq Sweep 300-1000 every 10 MHz - WIDEBAND SWEEP
' FR Hi-VHF choices:
' FR 0 15 0 0 174 3        ' Freq Sweep 174-216 every 3 MHz
' FR 0 29 0 0 174 1.5        ' Freq Sweep 174-216 every 1.5 MHz - PREFERRED
' FR 0 43 0 0 174 1        ' Freq Sweep 174-216 every 1 MHz - Hi-Rez
' FR 0 26 0 0 150 6        ' Freq Sweep 150-300 every 6 MHz - WIDEBAND SWEEP
' FR 0 64 0 0 54 12        ' Super Wide Freq Sweep 54-810 every 12 MHz
' RP choices in order of increasing calculation time:
' RP 0 1 1 1510 90 90 1 1 0 0        ' 1D Gain toward 0-deg Azimuth - SIDE GAIN
' RP 0 1 1 1510 90 0 1 1 0 0        ' 1D Gain toward 90-deg Azimuth - FORWARD GAIN
' RP 0 1 1 1510 90 180 1 1 0 0        ' 1D Gain toward 270-deg Azimuth - REVERSE GAIN
' RP 0 1 37 1510 90 0 1 5 0 0         ' 2D (Left only) Azimuthal Gain Slice
RP 0 1 73 1510 90 0 1 5 0 0         ' 2D Azimuthal Gain Slice - PREFERRED
' RP 0 73 1 1510 90 0 5 1 0 0         ' 2D Elevation Gain Slice
' RP 0 73 73 1510 90 0 5 5 0 0         ' 3D Lower Hemisphere reveals antenna (Fixed Freq)
' RP 0 285 73 1510 90 0 5 5 0 0        ' 3D Full Coverage obscures antenna (Fixed Freq)
EN
 

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DavidEC: Your TVFool Results indicate that you have strong signals, so your current Outdoor Antenna "should" be working just fine, esp. if weaker CBS and PBS stations work okay. I suspect you have a severe SWR mismatch problem that is only affecting KSMI (Ch30). First thing to try is to insert different lengths of fairly short pieces of Coax (1 to 6 ft) in the downlead, which "should" move the SWR Null to a different frequency (hopefully NOT affecting another station you want). Whether that works or not, it's still advisable to swap out the Balun and replace any Coax connectors that don't look secure...better yet, replace them ALL to hopefully eliminate any SWR problems. It is also possible that moisture has entered your downlead, which you can test by temporarily running a separate Coax to see if that fixes your problem....if so, you're at least ready for The Doctor.

In order to prevent a second UHF Antenna interfering with your R-S Antenna, you would need to combine them using either a C-M JoinTenna (out of production for many years) or a fairly pricy Single Channel Insertion Filter from Tin-Lee. HOWEVER, I would recommend using a UHF/VHF Combiner (aka UVSJ) to combine the VHF signals from the R-S to a new UHF Antenna, just in case there is something wrong in the R-S (or it's Balun). Since you have strong signals, you might want to start with a simple DIY UHF Hourglass-Loop or UHF Trapezoidal-Loop Antenna....perhaps start with No Reflector and add Reflector Rods or a Screen Grid if you need more:
http://imageevent.com/holl_ands/loops/uhfhourglassloop
http://imageevent.com/holl_ands/loops/uhfquadtrapezoidloop
http://imageevent.com/holl_ands/loops/uhfquadtrapezoidloop2xbars

A 4-Bay Bowtie would also be a good alternative...or your choice of a DIY Grey-Hoverman....

PS: A "Single channel" Antenna in the UHF Band is very difficult to design/build....typically they are at least THREE ADJACENT CHANNEL Antennas at -3 dB down points, with significant Gain for much more than several Channel positions above and below the desired Channel. So without external Filters, it WILL likely interfere with the Primary Antenna. For example, see Ch14-17 Yagis (which were actually Optimized for Ch14-15, but ended up being FOUR Channels wide):
http://imageevent.com/holl_ands/yagis
Blonder-Tongue UHF "Single Channel" Yagi's cover the entire New UHF Band with only five models: 6 Channels Wide for lowest channels and 11 Channels Wide for the highest channels.
Note that Intro to this webpage provides instructions for Resizing Antenna to ANY other Frequency Band.
 

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Your TV Fool report shows it should be easy to receive all the LOS stations in your list by pointing the antenna at about 335 degrees. It doesn't get much better than that. If you're having problems with one or more stations I'd check the antenna and cabling. Maybe something happened in the last 19 years. You show your antenna mounted at only 10'. Is it outside on the roof? If not, it needs to be.
It should be showing at about 20' off the ground, at the peak of the roof, it is mounted on two 10' poles for grounds and wind issues did not want the antenna to rip up and off of my roof, and all the cabling was replaced less than five years ago which made a marked improvement on the full power stations.
But no improvement on the 'Low Power' stations.

One thing you can not see in FOOL is local building( neighbors two story barn) and rised highway.. which in fact means I would have to go to about 40' to get above the average tractor+trailer rig on the highway that is to the north west of my home.. but then I am into local aircraft flight space as I was informed that I can not go higher than 30' which would be equal to a two story building.

So back to my main question.. can I build a 'tuned' antenna for UHF band USA Channel "30" with rapid drop off not to interfere with channels 24 and 36 on each side?
 

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So back to my main question.. can I build a 'tuned' antenna for UHF band USA Channel "30" with rapid drop off not to interfere with channels 24 and 36 on each side?
NO.....see above explanation....even a long Corner Yagi will provide -3 dB bandwidth of about 5-6+ channels on Ch30, with significant interference at twice that bandwidth, i.e. 5-6 channels away on either side from Ch30.
 

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Perhaps you can provide more detailed information on what you're working on....
I was reading through this forum/post around page-50-60 and came across this full-wave design. Outer circle 8" and inner 5" (dual frequency). I added about a 3/4" space between the large circles per one of the suggestions (I think they used 1"). I cut them out of aluminum roof flashing and glued them on plastic corrugated board (Like cardboard but plastic) using contact cement. I have 6 of them made and another 8 already cut.
The way I understand it is that I don't have to worry about phasing because it's full wave. But I misunderstood about being in parallel. It is simply two loops in parallel I guess, they weren't talking about hooking them up in an array. So I have no idea how to hook them up in an array.

I'll see if I can pick up some some AWG-12 wire so as to prevent losses. I'm assuming it needs to be solid, not stranded.
Anyone got an idea how to make an array of them?
I know they have to be vertical as pictured.
I was thinking about 3 rows of 4 each, for a total of 12.
Any suggestions appreciated!




I tried one and it seems to work. But I'm thinking it would do much better with an array of them.



TVFool for 75078 Zip:
http://www.tvfool.com/?option=com_wrapper&Itemid=29&q=id%3de1c60d208094ac
 

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So back to my main question.. can I build a 'tuned' antenna for UHF band USA Channel "30" with rapid drop off not to interfere with channels 24 and 36 on each side?
NO.....see above explanation....even a long Yagi or Corner Yagi will provide -3 dB bandwidth of about 5-6+ channels, with significant interference at twice that bandwidth, i.e. 5-6 channels away from Ch30.

Fol. example shows the extent of the problem, Rescaling DL6WU 22-Element Long Yagi from 432 MHz (Ham Band) to 569 MHz (Ch30). [Using a FOLDED Dipole and Re-optimizing would yield a 300-ohm Antenna.] Although it is very common for Yagi's to experience a rapid frequency roll-off on the high frequencies, they typically have a fairly slow roll-off on the lower frequencies:



Technical Info re Yagi's designed per DL6WU's formulas and look-up-tables can be found here, bearing in mind that they are for 50-ohm or 200-ohm (with 4:1 Balun) Antennas typically used in the Ham Radio Bands and hence are NOT Optimum for TV Bands:
http://dpmc.unige.ch/dubus/9102-4.pdf
http://www.qsl.net/vk2kfj/DL6WU.html
DL6WU's empirically derived design charts have been embedded into numerous on-line (e.g.K7MEM) and downloadable Yagi Calculators, including (FREEWARE) YagiCAD, which I used to generate the results shown above, after selecting one of the higher Gain Examples that came with the program.

I have a Ch30 "Single Channel" Optimization running overnight for a big Corner Yagi....based on a Rescale of it's Ch14 cousin, it might not have as rapid a roll-off on the high frequencies....
 

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It should be showing at about 20' off the ground, at the peak of the roof, it is mounted on two 10' poles for grounds and wind issues did not want the antenna to rip up and off of my roof, and all the cabling was replaced less than five years ago which made a marked improvement on the full power stations.
But no improvement on the 'Low Power' stations.

One thing you can not see in FOOL is local building( neighbors two story barn) and rised highway.. which in fact means I would have to go to about 40' to get above the average tractor+trailer rig on the highway that is to the north west of my home.. but then I am into local aircraft flight space as I was informed that I can not go higher than 30' which would be equal to a two story building.

So back to my main question.. can I build a 'tuned' antenna for UHF band USA Channel "30" with rapid drop off not to interfere with channels 24 and 36 on each side?
Your TV Fool report shows 10' off the ground.

Do you live right next to an airport? The height limit for towers is 200' without having to register the tower. I wouldn't take someone's word on 30'. Here's an FAA site about construction height near an airport:

https://oeaaa.faa.gov/oeaaa/external/portal.jsp

I agree that you're not going to be able to build a channel 30 only antenna. Even if you could more gain is not going to do anything. Almost everyone assumes that the station is too weak when it is not received. That often is not the problem and is almost certainly not your problem with KSMI which shows a Noise Margin of 46 dB. That's a huge signal! The signal is so strong that if it was running just 1.5 watts you should still receive it. You need to look elsewhere for the problem. Maybe you have a multipath issue which could be solved by getting the antenna above the local obstructions.

Without someone taking a spectrum analyzer to your home it's not possible for us to say exactly what your problem is.
 

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Your TV Fool report shows 10' off the ground.

Do you live right next to an airport? The height limit for towers is 200' without having to register the tower. I wouldn't take someone's word on 30'. Here's an FAA site about construction height near an airport:

https://oeaaa.faa.gov/oeaaa/external/portal.jsp

I agree that you're not going to be able to build a channel 30 only antenna. Even if you could more gain is not going to do anything. Almost everyone assumes that the station is too weak when it is not received. That often is not the problem and is almost certainly not your problem with KSMI which shows a Noise Margin of 46 dB. That's a huge signal! The signal is so strong that if it was running just 1.5 watts you should still receive it. You need to look elsewhere for the problem. Maybe you have a multipath issue which could be solved by getting the antenna above the local obstructions.

Without someone taking a spectrum analyzer to your home it's not possible for us to say exactly what your problem is.
While I don't live next to an airport.. I do live in a major military flight line, during the day time there is a flight over head almost every 30 minutes, luckily the flights stop when the sun goes down till about an hour after sun rise..

I do want to thank everybody that replied!

But on another note I guess that I only have one choice and that is install a new antenna set-up, and at the same time add another 10' to my current pole and guide wires to brace for the Kansas winds.

Any suggestions of a low cost: high VHF / UHF outdoor antenna, pre-amp, & five point (minimum, seven point would be ideal) distribution amp? : this way I will be replacing all current off air signal capturing hardware.

Before the local cable system went fiber/digital my current set up could pick up most all unscrambled cable channels.. by pointing the antenna directly at the cable/power lines straight north ..which in a way was a pain in the "B" due to ghosting/multiplexed signals in the VHF bands.
 

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David,

Your highest strength channel (adjacent 31) is at 64 db nm, and transmitting from the same tower as ksmi.

I don't know what tuner you have, but the best chance of picking up ksmi is to try out different tv tuners which may possibly be able to lock onto the ksmi channels. The chances of a lock are slim to none, but worth a try.

Wish u good luck
 

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"SINGLE CHANNEL" 18-EL YAGI with 14 RR CORNER REFLECTOR:

I uploaded 4nec2 Results for 18-Element Yagi with 14 Reflector Rods in a Corner Reflector:
http://imageevent.com/holl_ands/yagis/ch141715elfdyagi14rrcorneropt

Optimized for Ch30 (18.6 dBi on 566-572 MHz), the actual -3 dB Bandwidth is 50 MHz (540-590 MHz), which results in negligible reduction on Ch27 (17.8 dBi on 554 MHz Upper Band Edge) and Ch33 (16.8 dBi on 584 MHz Lower Band Edge).

I investigated Quarter-Wave Notch Filters awhile back, but they aren't going to be of much use, since the -10 dB Notch only had a Bandwidth of about 1 MHz (we need 6 MHz to Notch out each Channel) and ultimately 15 to 20 dB reduction is needed to reduce "co-channel interference" from the Yagi into the primary Antenna....which would require TWO Notch Filters for each of TWO Channel positions...and good luck getting it all to work, cuz they interact and the dimensions are VERY CRITICAL. So Tin-Lee Filters would be the only viable alternative.
 

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Can a notch filter do anything for the below readings (20 foot antenna height)?

KSMI ch 30.1 nm: 45.8 sig power: -45.1
KDCU ch 31.1 nm: 64.0 sig power: -26.9
 

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NO WAY: Quarter-Wave Notch only provided 10 dB Attenuation across 1 MHz...you would need to very carefully tweak SIX of them (and they interact with each other) to attenuate a typical 6 MHz DTV signal.....and if it's an ADJACENT signal, it's also going to seriously degrade Gain and SWR on the desired channel.

What CAN be done (if the geometry permits) is to use a pair of matching Horizontally Stacked Antennas to steer a NULL directly FORWARD towards the undesired direction and a BEAM(s) in the desired direction(s):
http://www.hdtvprimer.com/antennas/ganging.html
http://imageevent.com/holl_ands/stacked/horizontallystackeduhfantennas/hstacked2xcm4221hdhackednullbeam

 

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I just started reading this thread. Interesting. Why do you guys build your antenna's instead of just buying one?

Hope I didn't offend anyone by butting in.

This may be something for me to try someday.
 

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Holl, 6 notch filters for one channel? dang


SkyTrooper, no worries, ask away anytime. I can't be of much help tho, but Holl_ands sure can answer any questions you may have.

One thing I do know, is that the antenna's they design maximize gains for the latest tv frequency range, and also custom tuned antenna's can be designed to help bring in problematic channels.

Browse Holl_ands antenna modeling simulations here --> http://imageevent.com/holl_ands
 

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Thanks Don H. After I went to the link you provided, basically people are buying a antenna and modifying it to their needs. I also see the use of filters.
 
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