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Old 08-10-2014, 04:38 PM
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Holl, for the FF4 feed point, how does the balun attach. Should the balun wires be spread diagonally to attach, or should the balun wires make a sharp right angle?

Would it be possible to maximize the peak gain for ch 35?
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Old 08-10-2014, 04:39 PM
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Maintaining no reflector, can a narod be added to enhance the gain and lower the swr for high vhf?

Last edited by Don_H; 08-10-2014 at 04:46 PM.
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Old 08-10-2014, 05:19 PM
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Quote:
Originally Posted by Don_H View Post
Holl, for the FF4 feed point, how does the balun attach. Should the balun wires be spread diagonally to attach, or should the balun wires make a sharp right angle?

Would it be possible to maximize the peak gain for ch 35?
Doesn't really matter how you route the Balun Wires...

The max (or any other frequency point) for ANY Antenna can be Rescaled to another Frequency by multiplying ALL Dimensions by the Rescale Factor = Current Frequency / New Frequency.
Hence moving the Max Gain to a LOWER Frequency requires INCREASING all dimensions....and vice versa. When making drastic frequency changes, the Wire Size should also be changed according to the Rescale Factor.....but for changes within the same TV Band, it's okay to use the same Wire Size.
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Old 08-10-2014, 08:19 PM
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Ok, ty much for the info
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Old 09-13-2014, 07:28 AM
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I currently have been using a dual vertically stacked 4228 and I am looking to replace it with another antenna. I see the replacement for it is the 4228HD. I am not sure that that antenna can be stacked.
I was wondering what the best options would be
Choice 1 Stack a 4228HD
Choice 2 CM-3020
Choice 3 CM- 5020
Most of my viewing is on UHF, very little on VHF only a couple
I am also concerned with the weight of a stacked 4228HD
Thank You

Tom
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Old 09-13-2014, 05:21 PM
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Please Include a Link to your TVFool Report

Hi,

Zip 43952 has stations in several directions.

Please reply with your TVFool report and what stations / Networks you are interested in.

And the direction your current antenna is pointed. Do you have a rotor? Height of antenna would also be useful.

Are you using an amplifier?

TVFool
http://www.tvfool.com/?option=com_wrapper&Itemid=29

Pasting an image is not the same as a link. Here is mine.

Nani's ZIP Code
http://www.tvfool.com/?option=com_wr...d2434989f75b87

The experts here will then be able to help you better.

Be sure and enter your exact address in to TVFool, I see lots of terrain differences in that zip code.

Your exact address is hidden by TVFool.

SHF

Last edited by SFischer1; 09-13-2014 at 07:28 PM.
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Old 09-15-2014, 06:43 PM
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Quote:
Originally Posted by SFischer1 View Post
Hi,

Zip 43952 has stations in several directions.

Please reply with your TVFool report and what stations / Networks you are interested in.

And the direction your current antenna is pointed. Do you have a rotor? Height of antenna would also be useful.

Are you using an amplifier?

TVFool
http://www.tvfool.com/?option=com_wrapper&Itemid=29

Pasting an image is not the same as a link. Here is mine.

Nani's ZIP Code
http://www.tvfool.com/?option=com_wr...d2434989f75b87

The experts here will then be able to help you better.

Be sure and enter your exact address in to TVFool, I see lots of terrain differences in that zip code.

Your exact address is hidden by TVFool.

SHF
http://www.tvfool.com/?option=com_wr...d243367f6bb01b
40 foot tower and a preamp

Thank You

Tom
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Old 09-15-2014, 06:48 PM
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Quote:
Originally Posted by firemantom26 View Post
I currently have been using a dual vertically stacked 4228 and I am looking to replace it with another antenna. I see the replacement for it is the 4228HD. I am not sure that that antenna can be stacked.
I was wondering what the best options would be
Choice 1 Stack a 4228HD
Choice 2 CM-3020
Choice 3 CM- 5020
Most of my viewing is on UHF, very little on VHF only a couple
I am also concerned with the weight of a stacked 4228HD
Thank You
I would suggest a pair of 91XGs. Works great for me and my signals are weaker, farther away than yours and 2 edges. See my avatar. You can add a separate VHF antenna if you want.
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Old 09-15-2014, 06:49 PM
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Looks great


Sent from my iPhone 5 using Tapatalk

Tom
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Old 10-11-2014, 08:07 PM
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Here's the deal...



I have a MOHU leaf. Its the 30 mile range which is more than enough for the channels I need. I also have the Hauppage WINTV 2255 installed on my HTPC. My first test before mounting the antennae, I had signal to almost anything in range other than KVIE station, which sucked because that was my solution for the kid shows....

I found I received better reception near the window, so I got a longer coax cable and got it installed. I was able to get the same signal as before.

While browsing channels I eventually started dropping signal, and now I can't pull down any station. I"ve ran the signal setup on WMC as well as the setup program on the WINTV software and still nothing.

What am I doing wrong?

I'm tempted to get an outdoor attenae and mount it to the house.

This is my coverage. Any ideas?

http://www.tvfool.com/?option=com_wr...d243691389b81d
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Old 10-11-2014, 08:59 PM
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Naednek, I had a similar problem with an attic antenna, then one day I remembered that my issues started when they re-sided a tiny part of our house and they put foil faced insulation underneath. It was weird because I didn't lose the stations all at once, but one at a time. I tried everything to get our reception back. What finally worked was placing an old metal window screen directly behind the antenna. No scientific reason I am aware of, I just tried anything I could imagine and that screen happened to be in the attic.
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Old 10-11-2014, 09:53 PM
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Those Mohu and similar Leaf style antennas have reception limitations. Maybe add an inline amp such as Winegard LNA-100 or the Sears/Kmart Alphaline version and see if that helps. But if you upgrade the antenna, consider a Clearstream 2V from Walmart or an Antennacraft HBU-22. And possibly the inline amp.
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Old 10-12-2014, 05:50 AM
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Quote:
I'm tempted to get an outdoor attenae and mount it to the house.
Do that, it will solve a LOT of problems if properly selected and installed.
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Old 10-12-2014, 07:29 AM
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Quote:
Originally Posted by naednek View Post
Here's the deal...



I have a MOHU leaf. Its the 30 mile range which is more than enough for the channels I need. I also have the Hauppage WINTV 2255 installed on my HTPC. My first test before mounting the antennae, I had signal to almost anything in range other than KVIE station, which sucked because that was my solution for the kid shows....

I found I received better reception near the window, so I got a longer coax cable and got it installed. I was able to get the same signal as before.

While browsing channels I eventually started dropping signal, and now I can't pull down any station. I"ve ran the signal setup on WMC as well as the setup program on the WINTV software and still nothing.

What am I doing wrong?

I'm tempted to get an outdoor attenae and mount it to the house.

This is my coverage. Any ideas?

http://www.tvfool.com/?option=com_wr...d243691389b81d

If you're not receiving any stations at all something must have happened to the antenna or coax. You're in a very good location for the Walnut Grove stations and your TV Fool report shows you should be able to receive many other stations too. Indoor antennas can be problematic under any signal conditions so an outdoor antenna is always preferred. A small outdoor antenna like the ANT751 should work well for you. No preamp necessary.

I'd suggest posting further questions on the Sacramento OTA thread where there are more people familiar with the area.
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Old 10-13-2014, 09:53 AM
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I haven't done a search as this thread is 10 years and 16,000 posts old. But, for reasons explained below, I am thinking about putting a preamp (signal amplifier) in my OTA set-up.

Any of you much more intelligent people about this subject have recommendations on which one(s) you would recommend? Any one(s) to stay clear of?

The situation is that I am very close to my local (Omaha) stations so I get a great signal. But I am about 90 miles from some more channels in Sioux City, IA. Yesterday our local Fox affiliate did not carry the Bears game I wanted to watch. But the Sioux City Fox affiliate did. So it was great that I could watch my Bears. But my Magnavox MDR533 DVD recorder/tuner would not display the channel. So I couldn't pause the game/time shift/scroll through commercials. But my TV (Samsung 6600) would tune it in so that I could watch it. Clearly there is a difference in the tuners that is above my understanding.

Not just for the games but this opens up the entire subject of access to more viewing opportunities with a signal boost. And with that the potential using the DVD/tuner.

Any recommendations are appreciated.

Chubby, old guy in Omaha, Nebraska
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Old 10-13-2014, 11:44 AM
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Originally Posted by matonanjin View Post
... Yesterday our local Fox affiliate did not carry the Bears game I wanted to watch. But the Sioux City Fox affiliate did.
...
FYI: NFL Maps: Week 6, 2014

http://506sports.com/nfl.php?yr=2014&wk=6

Talk about NFL Gerrymandering.

---------------------------------

I think that the FCC may have eliminated the non sold out blackout rule.

http://www.sbnation.com/nfl/2014/9/3...ule-lifted-fcc

But nothing may change.

SHF
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Old 10-13-2014, 12:24 PM
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Quote:
Originally Posted by SFischer1 View Post
FYI: NFL Maps: Week 6, 2014

http://506sports.com/nfl.php?yr=2014&wk=6

SHF
Thanks, SHF! That map would have been helpful yesterday. but now I know that I can go to it. Thanks again, Ron

Chubby, old guy in Omaha, Nebraska
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Old 10-13-2014, 02:57 PM
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Quote:
Originally Posted by matonanjin View Post
Thanks, SHF! That map would have been helpful yesterday. but now I know that I can go to it. Thanks again, Ron
BTY, posting a link to your TVFool report will allow the experts to help you better on the original request.

http://www.tvfool.com/?option=com_wrapper&Itemid=29

Quote:
Originally Posted by SHF
San Francisco, CA - OTA

TVFool authors are fools

We need to tell the TVFool authors that something needs to be changed.

Too many people are not pasting the link.

Perhaps something like the words I typed a while ago, "Pasting an image of your TVFool results is not the same as posting the link because there is additional data available by clicking on links which of course cannot be done on an image". Your exact address will NOT be included.

"If you would like to share these results with others" is too weak IMHO.
SHF

Last edited by SFischer1; 10-14-2014 at 07:05 AM.
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Old 10-14-2014, 05:47 AM
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Hi,
Novice here and I need some advice and support. I'm going to dump AT&T U verse (Rip) and plan to install a antenna on my roof or attic. Don't know all the components that will make this all happen and I'm looking for advice. I have a been using an A/V receiver Yamaha RX- A 3020 into TV Sharp LC-70C8470U. I also have 2 other TV's in other rooms and they are cabled under the house. What path and components will make this happen into the TV. Do I need a Tuner, Amplified Splitter. What components and Antenna needed ? I'm going to by a DVR and I'm open to any and all suggestions.


I live in south Napa county in CA. http://www.tvfool.com/?option=com_wr...d2435fb2372d8a

Thanks in advance
John
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Old 10-14-2014, 07:39 AM
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Can someone give me the formula for computing the Total gain,Efficiency, Characteristics Impedance,Directivity,VSWR,Radiation pattern,Reflection coefficient, Power Transmitted and Power Received of a BATWING ANTENNA?please help me
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Old 10-14-2014, 07:44 AM
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Quote:
Originally Posted by howlinrock View Post
Hi,
Novice here and I need some advice and support. I'm going to dump AT&T U verse (Rip) and plan to install a antenna on my roof or attic. Don't know all the components that will make this all happen and I'm looking for advice. I have a been using an A/V receiver Yamaha RX- A 3020 into TV Sharp LC-70C8470U. I also have 2 other TV's in other rooms and they are cabled under the house. What path and components will make this happen into the TV. Do I need a Tuner, Amplified Splitter. What components and Antenna needed ? I'm going to by a DVR and I'm open to any and all suggestions.


I live in south Napa county in CA. http://www.tvfool.com/?option=com_wr...d2435fb2372d8a

Thanks in advance
John

First off, I'd recommend posting this in the San Francisco OTA thread where more people local to you will see it.

TV Fool shows all the SF stations are very strong and LOS so you shouldn't need the largest antenna just to get those. Even the Winegard HD7694P is probably good enough or something in the Antennacraft HBU series. Unless you have a very old TV they will all have tuners in them. A preamp should not be necessary but a distribution amp like the CM3414 would be helpful for 3 TVs. Use RG-6 coax. Quad shield in unnecessary. An outside antenna is always best but an attic antenna may be good enough for you. The antenna should not be looking into a tree or the side of a building.

Channel Master makes a DVR. I have a TiVo Basic that has 4 tuners in it which is more expensive overall but it works well.
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Old 10-14-2014, 10:30 AM
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Quote:
Originally Posted by Calaveras View Post
First off, I'd recommend posting this in the San Francisco OTA thread where more people local to you will see it.

TV Fool shows all the SF stations are very strong and LOS so you shouldn't need the largest antenna just to get those. Even the Winegard HD7694P is probably good enough or something in the Antennacraft HBU series. Unless you have a very old TV they will all have tuners in them. A preamp should not be necessary but a distribution amp like the CM3414 would be helpful for 3 TVs. Use RG-6 coax. Quad shield in unnecessary. An outside antenna is always best but an attic antenna may be good enough for you. The antenna should not be looking into a tree or the side of a building.

Channel Master makes a DVR. I have a TiVo Basic that has 4 tuners in it which is more expensive overall but it works well.

Thanks so much for your response and the suggestions. The CM3414 was on my list as necessary. The right antenna is my concern. not to small or big. I have also posted for advice in the SF OTA thread.
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Old 10-14-2014, 03:59 PM
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Originally Posted by yilits28 View Post
Can someone give me the formula for computing the Total gain,Efficiency, Characteristics Impedance,Directivity,VSWR,Radiation pattern,Reflection coefficient, Power Transmitted and Power Received of a BATWING ANTENNA?please help me
What batwing antenna are you talking about?
https://www.google.com/?gws_rd=ssl#q=batwing+antenna

The guys on the DHC forum that do computer modeling of antennas might be able to give you those answers:
http://www.digitalhome.ca/forum/forumdisplay.php?f=186

If you can not measure it, you can not improve it.
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www.megalithia.com/elect/aerialsite/dttpoorman.html

Last edited by rabbit73; 10-14-2014 at 04:05 PM.
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Old 10-14-2014, 06:23 PM
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Quote:
Originally Posted by yilits28 View Post
Can someone give me the formula for computing the Total gain,Efficiency, Characteristics Impedance,Directivity,VSWR,Radiation pattern,Reflection coefficient, Power Transmitted and Power Received of a BATWING ANTENNA?please help me
Can you be more specific???? Perhaps it's a variation of one of the fol. BATWING Antennas analyzed using 4nec2:
http://www.digitalhome.ca/forum/show....php?p=1004148
http://www.digitalhome.ca/forum/show....php?p=1005063

The late L B Cebik analyzed the BATWING, which MIGHT be on the fol. (OLD & NEW) websites (requires FREE Registration):
http://www.cebik.com [OLD]
http://www.sage-american.com [NEW]


Or perhaps you mean one of the following Antennas, which RESEMBLES a BATWING:
http://www.digitalhome.ca/forum/show....php?p=1319268

Last edited by holl_ands; 10-14-2014 at 06:26 PM.
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Old 10-14-2014, 08:33 PM
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we used antenna magus software for our simulation but we don't know where the results came from, we need some proof. We need formulas and calculations... please help us?
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Old 10-15-2014, 08:17 AM
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Your question is devoid of any content that would be useful in trying to determine what it is you are asking for which leads me to suspect that you simply don't know what you're actually looking for.
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Old 10-15-2014, 08:54 AM
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We just need to prove the results that we got from the software antenna magus, we need it for our defense in our antenna project. Impedance,VSWR,Refelction Coefficient,Total Gain and wire diameter are some of the formulas we need.
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Old 10-15-2014, 11:02 AM
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There are several batwing antennas in the world which one are you modeling? You need to provide the make and model of the antenna or at least a detailed physical description. As was pointed out in previous posts your antenna may already have been modeled abd the results published.
John
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Old 10-15-2014, 06:06 PM
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Quote:
Originally Posted by yilits28 View Post
We just need to prove the results that we got from the software antenna magus, we need it for our defense in our antenna project. Impedance,VSWR,Refelction Coefficient,Total Gain and wire diameter are some of the formulas we need.
You seem to be unwilling to tell us about your antenna, so you must consider it to be proprietary information.

The only way that I know how to prove your results are:

1. Hire someone to use other antenna design software to confirm your results.

4nec2 & Other Antenna Design Modeling Software
http://www.digitalhome.ca/forum/showthread.php?t=83772

4nec2
NEC based antenna modeler and optimizer
by Arie Voors
http://www.qsl.net/4nec2/

2. Construct your antenna and have the parameters in question measured at an antenna lab, to include comparison with an existing batwing antenna from a competitor.

https://www.google.com/search?output...na+magus&btnK=

http://www.antennamagus.com/ (a South African company)

https://www.cst.com/Content/Media/CS...agus-Flyer.pdf

http://www.antennamagus.com/contact-us.php

If you can not measure it, you can not improve it.
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www.megalithia.com/elect/aerialsite/dttpoorman.html

Last edited by rabbit73; 10-15-2014 at 06:24 PM.
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Old 10-16-2014, 12:50 AM
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Even SIMPLE Antenna are actually very complicated and do NOT conform to some sort of "algebraic formula(s)" for description of (Horizontal+Vertical=Total) Forward Gain vs Frequency, 3-Dimensional Gain vs Frequency (not just a 2-D Horizontal or Vertical "slice"), Complex & Real Impedance vs Frequency and (where appropriate) Front/Back & Front/Rear Ratios vs Frequency, Beamwidth and Sidelobe Null Depth. And, of course, WIDEBAND Antennas are more complicated than Narrowband Antennas.

As described here, even a SIMPLE Yagi-Uda Antenna defies a closed-form solution:
http://en.wikipedia.org/wiki/Yagi-Uda_antenna
http://www.sm.rim.or.jp/~ymushiak/sub.yua.charts.htm [Almost all Quarter-Wavelength Dimensions, Just ONE of MANY Charts]
http://www.sm.rim.or.jp/~ymushiak/sub.ire.chart.htm [Folded Dipole]

Note that a presumably "optimized" 3-Element Yagi-Uda (IF nearly ALL dimensions were Quarter-Wavelength) would have a Characteristic Impedance of 28-ohms, which does NOT match very well to the usual 50-ohm Transmitter....and 4:1 Balun does NOT help...although a CAREFULLY designed Folded Dipole Active Element CAN minimize the SWR. Fortunately, modern Optimizers search across MANY different design parameters and find the set of dimensions which provide the "best" OVERALL COMPROMISE against a set of "balanced" performance criteria ("Target Function" in nikiml's Optimizer).

Mr. Yagi and Mr. Uda (and most other Antenna Designers) actually determined SOME of these performance parameters by constructing and TESTING hundreds if not thousands of Antennas with small changes in the various Dimensions and charting the results to find the "better" set of dimensions, recognizing that there are trade-offs of Gain vs SWR vs F/B & F/R Ratios. They (and others) did this for a small number of Elements...eventually adding a large number of (usually non-optimum) EQUALLY Spaced Directors, as described in fol. National Bureau of Standards (NBS) TN-688 "Yagi Antenna Design", Oct 1976:
http://tf.nist.gov/general/pdf/451.pdf

Various Software programs for Yagi, LPDA and other Antenna types have used Look-Up-Tables based on the above performance charts to "design" GOOD, but perhaps not OPTIMIZED Dimensions (as we do using 4nec2, nikiml's Scripts and other programs). For a given set of Element Diameters, there are FIVE Variables in a simple 3-Element Yagi Antenna, and 1+ONE additional Variables if ALL additional Directors are the same Length (like 91-XG) and 1+TWO additional Variables if additional Directors are allowed to be different Lengths for even better results.

The only way to verify an existing design or to "find" GOOD...or Optimized Dimensions for a given Antenna type is to use a Simulation Model (like NEC2 Engine within 4nec2 & nikiml Optimizer). Although there are alternative techniques, the most popular is the Method of Moments (MoM) calculation algorithms embedded within NEC2 & NEC4. MoM is an exhaustive process that calculates the effect that each and every small segment in each of the wires affects the mutual impedance coupling to each and every other segment in every other wire, deriving the performance parameters from these calculations.

Fortunately, 4nec2 is FREE and "only" requires the input of a set of "Wire Statements" that define the starting and ending points in X,Y,Z Coordinates....and a few other Environment and Housekeeping statements. The nikiml Optimizer requires one more step: the Optimization Dimensions need to be expressed as SYmbol Variables, rather than numeric X,Y,Z.

My ANTENNA SIMULATIONS link below leads to over 500 4nec2 models analyzed (nearly all TV Broadband), of which about 100 used nikiml's Python Optimization Scripts, so I understand it's become a fairly daunting process to sort through and find a good "example" to start with.

I would recommend UHF HOURGLASS-LOOP as a good SIMPLE 4nec2 and Optimization example, using only THREE SYmbol Variables: Height, Width and Source Gap (aka Length of Balun+Center Wires):
http://imageevent.com/holl_ands/dipoles/uhfbowties

If appropriate, look at UHF SOLID TRIANGLE BOWTIE as a good 4nec2 and Optimization example using Triangular structures to simulate a SOLID sheet of metal, using only THREE SYmbol Variables: Bow Length, Tine Separation and Feedpoint Separation:
http://imageevent.com/holl_ands/loops/uhfhourglassloop

Last edited by holl_ands; 10-16-2014 at 01:56 AM.
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