How to build a UHF antenna... - Page 160 - AVS Forum
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post #4771 of 4798 Old 06-07-2013, 03:59 PM
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Quote:
Originally Posted by holl_ands View Post

I cringe whenever someone says they're building "DB-4" or "U-Tube" type 4-Bay Antenna cuz BOTH are way TOO SMALL for the NEW UHF Band and are ineffective in Hi-VHF Band:
http://imageevent.com/holl_ands/multibay/4bay/chartsnorefl

What you want to use is one of the larger "M4" designs by mclapp, which outperforms the CM4228HD 8-Bay in BOTH UHF & Hi-VHF Bands:
http://imageevent.com/holl_ands/multibay/4bayrefl [DB-4 is at bottom of webpage]

http://photos.imageevent.com/holl_ands/multibay/8bayrefl/cm4228hd/huge/CM4228%20vs%20CM4228HDvs%20Super4bay%20M4%20-%20UHF%20Gain.jpg

http://photos.imageevent.com/holl_ands/multibay/4bayrefl/m410x95/huge/PerDwgsM4_%2010x9_5_BowSwp_2.0in_DblAngldRefl_4_5in%20-%20Hi-VHF%20Raw%20Gain.jpg

Saw the "M4" design before, looks simple enough. How does it compare to the Gray-Hoverman design? http://www.wikihow.com/Make-a-High-Performance-Indoor/Attic-Dtv-Antenna
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post #4772 of 4798 Old 06-07-2013, 04:57 PM
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There are many variations of Grey-Hoverman Antenna, most of them with multiple Reflector Rods....and to extend performance into Hi-VHF Band: NARODs (Not A Reflector Or A Director). The link you provided is for a Single Bay Grey-Hoverman (SBGH) without any Reflectors or NARODs, also known as GH0, with NET Gain between 6 and 12 dBi. Unfortunately nikiml charts NET Gain vice Raw Gain, which I believe is more meaningful...but for low SWRs, they're close. I also just added analysis of the Autofils SBGH (NO Reflector) variation, based on a 4nec2 file posted by oldsparks:
http://clients.teksavvy.com/~nickm/gh_u/gh0_10u45.htm
http://imageevent.com/holl_ands/grayhoverman/sbghnoreflector

There are several variations in SBGH (usually with multiple Reflector Rods), variations on the ORIGINAL Doyt Hoverman design (see Type 1):
http://imageevent.com/holl_ands/grayhoverman
NOTE the numerous links to additional G-H info......

G-H versions comparable or exceeding the UHF and Hi-VHF performance of mclapps's M4 require numerous Reflectors and NARODs....which are fairly complicated to build compared to M4. Feel free to browse through the alternatives on the fol. websites:
http://clients.teksavvy.com/~nickm/
http://www.jedsoft.org/fun/antennas/dtv/gh.html
http://www.digitalhome.ca/ota/superantenna/performance.htm
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post #4773 of 4798 Old 06-07-2013, 06:25 PM
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Summit Source may still sell Antennacraft versions of the Grey-Hoverman.
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post #4774 of 4798 Old 06-08-2013, 08:32 AM
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Going to build an antenna based on the mclapp m4 design. Seems fairly straight forward, should be a fun afternoon. Can someone point me to the good set of diagrams/instructions/videos? Is this a good reference link => https://sites.google.com/site/maycreates/ota-setup/mclapp-4 ?

Thanks... looking forward to this little project.

Think this is the original site -> http://m4antenna.eastmasonvilleweather.com/instructions/4%20Bay%20Kit%20Assembly%20Instructions.html
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post #4775 of 4798 Old 06-08-2013, 11:29 AM
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Those are the correct links for mclapp M4....note that I modeled two sizes, the larger is a bit better for NEW UHF Band.
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post #4776 of 4798 Old 06-08-2013, 03:17 PM
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A bit off topic but where is a good place to pick up wiring? 10 gauge copper wiring is about $1 per foot @ homedepot / lowes & looks like it needs a little under 30'.
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post #4777 of 4798 Old 09-28-2013, 05:17 PM
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I am attempting to attach my top hat narods (designs shown here; Post 3042, pg. 102) to a DBGH. I am in need of some explanation though on installing or attaching these narods to the DBGH. I am unable to find any direction in this regard online.  There are plentiful design and creation instructions but there seems to be nothing on how to attach or install these, including if they are to make contact somewhere with elements or if not the distances from elements or if there are any slants or angles from vertical recommended for installing... etc....?... Anyone have any detailed attachment instructions with some pics or something on these Top Hat Narods on a Gray Hoverman (mine is a Double Bay Gray Hoverman) .  Thanks.. :rolleyes:TPTOOLS

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post #4778 of 4798 Old 09-29-2013, 01:42 PM
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300ohm invented the narods. As him on this thread:
http://www.digitalhome.ca/forum/showthread.php?t=121956&page=59

If you can not measure it, you can not improve it.
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post #4779 of 4798 Old 10-20-2013, 02:24 AM
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I currently have a cheap 2-bay coathanger whiskers I threw together out of laziness and lack of extra parts on hand to build more bays.

I am tired of turning it to get a more distant channel.

Question: Is there any advantage to adding just a third bay instead of two more? Or does it have to be in pairs? So 2 or 4 but not three?

By the way I was able to just take a FM reception wire and join it into the array by using an old 300ohm splitter I had around and using it in reverse, UHF from the whiskers, VHF from the wire and it turns 300ohm into the 75ohm coax. Seems to work, signal is low but good enough for my TV, where the whiskers alone could not get the VHF signal.
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post #4780 of 4798 Old 10-20-2013, 05:36 PM
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UHF 3-BAY BOWTIE - NO Reflector:

I expected that the Gain Pattern would shift upwards, but i was surprised at how SMALL the shift was across the UHF Band....and how LARGE the shift was in the middle of the Hi-VHF Band:
http://imageevent.com/holl_ands/multibay/uhf3baybowtienorefl

UHF Gain for the 3-Bay Bowtie turns out to be about half-way between an Optimized Super-2-Bay (M2) and an Optimized Super-4-Bay (M4) with no more than a mere 5-degree up-angle in the Elevation Gain Pattern...which might even offer a couple tenths of a dB improvement in some situations (e.g. Mt Wilson in L.A.).

Hi-VHF Gain points directly UPWARDS at 189 MHz as the antenna becomes more of an end-fire array (like a Yagi pointing upwards) that a Flat Panel Array. This results in a huge Gain Hole of up to -5.8 dBi (that's minus) on 189 MHz, affecting all except the lowest and highest Hi-VHF Channels.

============================================================
Since you said that you are using a "Coat Hanger" 2-Bay Bowtie Design, I hope that you are using one of the larger designs optimized for the NEW UHF Band, rather than one of the several TOO SMALL designs that infect the internet. Whisker Length should be at least 8.5 and preferably 9.5-in with Bowtie-to-Bowtie separation of 9.0-in as used in mclapp's M2 and M4. Also note that these larger designs provide significant Hi-VHF Gain, and when used with an appropriately sized Reflector, are directed FORWARD, unlike smaller designs:
http://imageevent.com/holl_ands/multibay
FYI: M4 (9.5x9.0) is Optimum size for NEW UHF Band, except when used with the Double-Angle-Reflector the slightly larger M4 (10x9.5) is a bit better, esp. on lower channels.

If you go to www.tvfool.com and "Check Address for Local TV".....then Copy/Paste the results URL (webaddress at top of browser). From the report we''' be able to determine what sort of antenna you need for VHF channels....there are several very simple & cheap DIY projects to chose from....
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post #4781 of 4798 Old 02-05-2014, 05:58 PM
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Hey everyone - We're cutting our cable and was looking into antennas and came across this fantastic thread.  Thanks so much for all of the info! After a few hours of reading I think I might try and make mclapp's M4 antenna but I had a couple of questions:

 

Here is my TV Fool report:

 

http://www.tvfool.com/?option=com_wrapper&Itemid=29&q=id%3d0b867b3d28de77

 

1) Based on my nearby stations, what antenna length and spacing would be best? I'm considering 9" with 8.5" spacing.  

2) Am I better off with, or without a reflector. 

 

Thanks again, and I'm looking forward to building this antenna!

 

Munnjo 

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post #4782 of 4798 Old 02-07-2014, 07:30 PM
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Me again.  Well I'm a bit discouraged now.  I made the plunge and tried my hand at a mclapp M4 style antenna.  I tried used 9.5" whiskers and 9" spacing but unfortunately I wasn't able to pick up a single channel.  Not even close.  I thought I did everything correctly but feel free to take a look at my photos to see if I missed something.  Perhaps the broadcasts just aren't strong enough here in southwestern Ontario.

 

Here is my TV Fool report again

 

Thanks for taking the time to look.  Any advice would be appreciated!

 

 

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post #4783 of 4798 Old 02-07-2014, 08:33 PM
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I can't see, but perhaps the Crossovers are shorted out...separation should be 0.5 to 1.0 inches.

Or perhaps you have very high Indoor Loss...try temporarily moving the antenna outside your door to see if you get some signals, rotating it through several directions.

I also wouldn't rule out some sort of Cable or Balun defect problem.....and did you rescan for OTA (NOT Cable) signals??
Even indoors, you should be getting Ch28....but may need to add a Reflector for anything other than LOS stations.

Without a Reflector, Hi-VHF Raw Gain for M4 is only 3.5 dBi with SWR under 2.7, which may be inadequate for
Ch9 & Ch11....and perhaps also Ch13 if your Indoor Loss is very high. Also note that these three Hi-VHF
stations are on THREE different directions, which WILL require rotating the Antenna when you change channels.
You might be better off using M4 with Reflector for UHF and a broadband Hi-VHF Hourglass-Loop for Ch9-13,
connected together using a VHF/UHF Combiner (Radio Shack, Antennas-Direct or UVSJ from Pico-Macom or Holland).

With Mclapp's recommended Double Angle Reflector, Hi-VHF Raw Gain is 8.3 to 8.6 dBi, although Hi-VHF SWR
becomes excessive, that may or may not be an issue.
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post #4784 of 4798 Old 02-07-2014, 08:56 PM
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Thanks for the quick response!  Well this shows my complete lack of knowledge on this stuff.  I was just trying to flip through the channels.  I did an auto scan and it found one channel (36).  I moved the antenna outside and did another quick scan and it picked up channel 6 in both HD and SD.  

 

I checked the separation on the crossovers and they were a tad close - I separated them a bit and I think it helped.  I'll have to keep playing around with it.  Thanks again for your help.

 

Edit: I moved the antenna further outside and was able to get 7 channels.  I think I might just have a lot of indoor loss (brick bungalow).  It looks like outdoor mounting is likely my best option.  I'll also look into reflector designs.  Thanks again for your help.

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post #4785 of 4798 Old 02-07-2014, 09:11 PM
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You may need to Rescan (Add Channel Scan?) as you rotate the Antenna to all (4?) expected strong signal arrival directions.
BTW: In your TVFool Report, I had to click on "Pending Applications" to see Digital Ch6.
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post #4786 of 4798 Old 02-07-2014, 09:15 PM
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That's a good idea.  Since I have broadcasts coming from so many different directions should I try this without a reflector first?

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post #4787 of 4798 Old 02-08-2014, 05:11 PM
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Yes, rotating around in different directions as you rescan each time. Which 7 channels (sub-channels?) did you get???
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post #4788 of 4798 Old 04-18-2014, 09:50 PM
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I currently have a good outdoor antenna that picks up most stations with ease.. except for the local "LP-DT-UHF" stations.

I have read on "WEB" about making a 'signal tuned' antenna.

But none of the posting / blogs / how to's; explain how to combine the antenna output to a single coaxial cable.

In my market area (zip code 67216) I get a 75%+ signal on the major stations which I receive except:
KPTS-LD 8.1 PBS; RF Channel: 17
KGPT-DT 26.1 IND, RF Channel: 24
KCTU-LD 43.1 IND; RF Channel: 43
: On these stations I only get a 40% signal on my best day.

So I am thinking of building my own "Loop" or "Bow Tie" (Such as this one: http://www.happy-monkey.net/dtv-antenna/) antenna tuned to these channels to help increase the amount of signal and combining with my main antenna..

So how can I combine the signals with out degrading other channel signals?

I just noticed that it seems that my current antenna may have a design flaw and breaks down / loss of signals approximately every step up in channel groups? ((7+17)+17)...
:David
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post #4789 of 4798 Old 04-19-2014, 10:53 AM
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FYI: TVFool results for your zipcode....it would help if you could post result for YOUR precise position:
http://www.tvfool.com/?option=com_wrapper&Itemid=29&q=id%3d5b94c98c93a84e
I see that Ch17 and Ch43 are about 35-degrees away from the direction of most other strong stations.

You should let us know what you were using for a UHF Antenna. If very high Gain (e.g. 8-Bay or 91XG), you may need to retweek the antenna to favor the 353-deg direction. A medium Gain Antenna (e.g. 4-Bay) should have a wide enough beamwidth to readily cover 35-deg station spread without requiring very careful directional tweaking. And if using an old UHF Antenna designed for the OLD UHF Band (esp. DB-4), Gain on the lower UHF Channels is very poor, which could explain poor performance on Ch17 and Ch24.

The missing stations are quite strong (at the ZIPCODE location....YMMV) so perhaps there is an SWR problem on the download that needs to be investigated...it MIGHT explain why only SOME stations are degraded. Carefully check each connection (esp. look for stray shield wires shorting out to the center wire) and replace with a new connector if it looks suspect. You can also try adding short lengths of coax (e.g.6-18-in long) to extend the overall length of the downlead, hopefully avoiding having an SWR Null on the END of the Coax. Moisture in the Balun and/or downlead Coax could also degrade SWR...try temporary bypassing the entire downlead with a new Coax.
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post #4790 of 4798 Old 04-19-2014, 10:22 PM
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Quote:
Originally Posted by holl_ands View Post

FYI: TVFool results for your zipcode....it would help if you could post result for YOUR precise position:
http://www.tvfool.com/?option=com_wrapper&Itemid=29&q=id%3d5b94c98c93a84e
I see that Ch17 and Ch43 are about 35-degrees away from the direction of most other strong stations.

You should let us know what you were using for a UHF Antenna. If very high Gain (e.g. 8-Bay or 91XG), you may need to retweek the antenna to favor the 353-deg direction. A medium Gain Antenna (e.g. 4-Bay) should have a wide enough beamwidth to readily cover 35-deg station spread without requiring very careful directional tweaking. And if using an old UHF Antenna designed for the OLD UHF Band (esp. DB-4), Gain on the lower UHF Channels is very poor, which could explain poor performance on Ch17 and Ch24.

The missing stations are quite strong (at the ZIPCODE location....YMMV) so perhaps there is an on the download that needs to be investigated...it MIGHT explain why only SOME stations are degraded. Carefully check each connection (esp. look for stray shield wires shorting out to the center wire) and replace with a new connector if it looks suspect. You can also try adding short lengths of coax (e.g.6-18-in long) to extend the overall length of the downlead, hopefully avoiding having an SWR Null on the END of the Coax. Moisture in the Balun and/or downlead Coax could also degrade SWR...try temporary bypassing the entire downlead with a new Coax.

?: You should let us know what you were using for a UHF Antenna.
A: 19+ Year (installed summer of 1995) Old 'Radio Shack' VHF/UHF antenna... over all length is over 6' and use to allow me to pull in my local PBS station when they were still VHF... it was the largest/strongest sold at the time and cost close to $100.00

!: SWR problem
?: What would this be ?

!: ".... END of the Coax. Moisture in the Balun and/or downlead Coax ...."
A: All cables/balun's were replaced about two (maybe three) years ago when a DirecTV installer cut the wrong lead entering my home in error. Also all connections were covered in silicone sealant.

Just to the west/north-west of my home is a 2.5story "garage/barn" and I have to aim the antenna to the south of the barn to even get any signal, if aimed per-GPS/compass, I aim right at the center of the barn and my signal drops by 50% on my strongest signals!!
Right now my antenna is about 20' off the ground and to get over this building I would have to go to 35+ feet, which I was told I don't want to do with Kansas winds.
I have a portable DTV and on my house side of the building I get no/low signal, I walk to the west side of the building I get close to 80% signal, on the same station!
I have a single story house...

:David
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post #4791 of 4798 Old 06-18-2014, 02:29 PM
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Quote:
Originally Posted by serndipity View Post
Quote: Originally Posted by d510d180

I also found this (you probably need to login, sorry, the picture is below).
http://www.lumenlab.com/forums/index...dpost&p=298078

In a nutshell, he's cutting a dual loop in an aluminium cookie plate. Outer diameter 8.0 inches (for channel 14, ~470 MHz) and inner diameter 5.0 inches (for channel 61, ~750Mhz).



But my question is about the coax joint: this guy has simply hooked the coax on each end of the two loops. I think this is suspicious. Do you think this requires a 1:1 balun? Is it that important (what are the effects of not using such balun)? Any do-it-yourself 1:1 balun specs for us?

Thanks.


I am the person responsible for the design on www.lumenlab.com.

Please note that I did use a 1:1 current balun.....which was simply a ferrite bead slipped over the coax.

The purpose of any balun is to prevent the coax shield of feed line from acting as part of the antenna (e.g. not pick up multi-path).

The 1:1 current balun design you show in post 1555 is correct as well (slipping a ferrite core over the coax is just much simpler).

Since these baluns are not transformers....they are 100% efficient.

I like this design and I'm going to build it. I have acquired some aluminum roof flashing to cut out the double loops. But I had a couple of questions which I'm hoping someone can help me with (I'm a newb as far as antennas):
1. If I use more than one then I hook them in parallel? All the left sides get hooked together and all the right sides?
2. Since it is full wave then I don't use crossed phasing lines. Right?
3. How close to each other can they be if I use more than one? Do they have to be 8" (one full wave) apart? Or would 4" be good?
4. Is there a limit to how many I can add? What would that do to the impedance? Does it matter?
5. I saw some UHF ferrite cores on Ebay which look like they might slip right over a coax cable. If I get those then I don't need a balun right? Does the impedance matter then?

Thanks for any help!

http://www.tvfool.com/?option=com_wr...e1c60d208094ac

Last edited by FriedOkra; 06-19-2014 at 02:15 PM. Reason: Adding TV Fool map info
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post #4792 of 4798 Old 06-23-2014, 01:36 AM
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Can anyone estimate the gain of this GE24792 (aka GE34792) attic antenna based on its configuration? Or how it might compare to a DIY antenna?
http://www.jascoproducts.com/product...m#.U6fhpii_1c6

The manufacturer will not tell me any gain figures so I don't know if I should build an antenna or get the GE unit. According to the manual/guide, the GE covers VHF 170-220 MHz & UHF 470-700 MHz. I need VHF channel 12 in addition to UHF which means building a basic UHF antenna will not work for me.

Any comments or suggestions would be appreciated.
Thanks.
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post #4793 of 4798 Old 06-23-2014, 02:11 PM
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I'll take an educated guesstimate.....

The largest Element, a Folded Dipole, is the only one that contributes to Gain in the Hi-VHF Band (Ch7-13). Without all of that extra metal probably DEGRADING performance, a perfect Hi-VHF Folded Dipole provides about 1.5 dBi on Ch 7 + Ch13, with max of about 2.0-2.1 dBi on Ch 9-10....but that is ONLY when it is the DRIVEN Element....which MAY ONLY be the case in the above antenna if it is connected to the adjacent UHF Element via a Feedline structure.....which I can't verify one way or another:
http://imageevent.com/holl_ands/loops/folded
BTW: Although modeling should be done to determine for sure, from other antennas I've analyzed, I suspect that there will be slightly MORE Hi-VHF Gain in REVERSE than FORWARD. So you'll need a fairly strong Hi-VHF Band signal to use this antenna.

UHF performance is a bit more difficult to guestimate since it's unknown whether there is a LPDA Feedline interconnecting ALL Four Elements, providing a wider Bandwidth at the expense of max Gain....or if the back TWO elements are Driven (a Log-Yagi)....or if ONLY the second from the back (UHF) Element is Driven in a conventional Yagi configuration.

There is a 4-Element Yagi on the (Australian) market that provides 6-8 dBi on UHF and 6-9 dBi on UHF when the back element is extended to provide some 0 dBd = 2.1 dBi in VHF Band (e.g.Vantenna):
http://matvtech.com/hills-vantenna

The "Parabolic" Reflector Elements on the subject antenna will improve UHF Gain by maybe 2.0-2.5 dB for a Max of about 10 dBi on highest frequency (no doubt designed for AUS 806 MHz Band) so perhaps 8 dBi on 698 MHz and I would guesstimate about 5 dBi on 470 MHz.

Fracarro BLU220F (similar to Triax 108810) is a FIVE-Director plus Active Element Yagi with Corner Reflector which (per catalog) provides 10 dBi on 470 MHz rising to 12 dBi on 698 MHz and 13 dBi at 806 MHz, similar to fol. "PLUS" model.
http://www.frequencydistribution.co.uk/product/fracarro-blu220f-22-element-tv-aerial-12db-wideband
http://www.triax.com/FindProduct/ProductDetails.aspx?product={672B2876-E579-4AAC-9B12-9F44EFA6EED9}

However, IF the above antenna is a Yagi-type, then it only has TWO-Directors, which can be expected to reduce the Gain by about 4 dB, hence we can guesstimate about 6-8 dBi for the above Antenna, which is consistent with the 5-8 dBi guesstimated earlier.

Alternatively, if it's an LPDA design, I would guesstimate Gain is roughly 5-7 dBi, fluctuating across the band, since there are only a few Elements in the design.

Note that the above Antenna (no doubt also designed for the OLD 806 MHz Band) uses smaller "loops" with closer spacing than the comparison Antennas....unless it's just an optical illusion, this might reduce our UHF guesstimates by another 1 dB or so...

Unfortunately, after searching Australian, UK, Italian, Spanish and Polish Antenna Catalogs, there are NO OTHER Antennas I found that even come CLOSE to having the same design as the subject Antenna.....and the Fracarro/Triax Corner Yagi design with only FIVE Directors is a rarity....most Yagi designs use quite a few more. And I still don't know if the wider Hi-VHF Element is acting as either an Active LPDA Element....or is simply a much less effective Passive Reflector....
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Last edited by holl_ands; 06-23-2014 at 03:59 PM.
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post #4794 of 4798 Old 06-23-2014, 07:48 PM
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My DIY Gray-Hoverman antennas on my 40-foot tower. Just built them this week. The elements used on the bottom two were re-purposed from DIY antennas I have been using for the last five years. They held up surprisingly well. Happy DIYer.



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post #4795 of 4798 Old 06-24-2014, 02:21 AM
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holl_ands -

Thanks for all the information. I'll have to see what kind of DIY plans there are for an antenna that includes VHF high band.
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post #4796 of 4798 Old 06-24-2014, 12:54 PM
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I looked back at your TVFool report in post #3 in your original "Chicago location" thread:
Chicago: Signal Strength varies on only one OTA channel

You have VERY STRONG stations that are LOS and only 20-miles away including independent Ch6 [DO YOU REALLY NEED THIS ONE] and CBS on Hi-VHF Ch12. Although it's not easy to guesstimate the amount of Loss due to Attic location ( est. 13 dB +/- 7+ dB) or Tree Loss (depends....), you "shouldn't" need more than a Medium-Gain Antenna for either UHF or Ch12. As has been mentioned before, you probably need to move the antenna around the Attic until you find the "sweet spot"....unfortunately, your current monster Combo isn't easy to move. Due to the VERY STRONG signals, I do NOT recommend using a Preamp due to likely Overload degrading weak signal reception.

Since you expressed interest in a DIY project, I would recommend starting with the very simple Hi-VHF Hourglass-Loop with either NO Reflector and if that isn't adequate, adding Reflector Rods (Wires) per one of the designs found here:
http://imageevent.com/holl_ands/loop...fhourglassloop
Note that Hi-VHF Hourglass-Loop is one of very few Antennas that performs about the SAME whether using smallish AWG10 or AWG12 or much larger 1/4-in wire sizes. A UHF/VHF Combiner (aka UVSJ) is used to combine VHF and UHF signals. If Ch6 is of any interest to you, it is so strong the Hi-VHF Hourglass-Loop will probably also work for that channel.

For UHF, I recommend mclapp's M4 (10x9.5) Super-4-Bay with Double Angle Reflector (my larger, higher Gain FF4 Super-4-Bay with even larger Double Angle Reflector is probably overkill). Note that it has significant Gain in Hi-VHF Band, although SWR is Excessive, which may or may not be an issue in your system. It will probably fit in-between Attic Trusses and hence can be used with a Rotator if you want to check out other, further away stations:
http://imageevent.com/holl_ands/multibay/4bayrefl

I also Optimized two alternative Hi-VHF/UHF Combo Antenna designs for a Super-4-Bay Antenna that operated well in Hi-VHF band at the expense of somewhat lower Gain in UHF Band:
http://imageevent.com/holl_ands/mult...sreflectorrods

There are also Optimized Hi-VHF/UHF Combo Grey-Hoverman type designs on nikiml's website:
http://clients.teksavvy.com/~nickm/gh_n_uV.html

Also Bowtie-In-Loop types found here:
http://imageevent.com/holl_ands/loops

And the best of the "Inside a 2-ft x 3-ft Metal Picture Frame"...a 2-Square Centipede:
http://imageevent.com/holl_ands/loop...pedeinrectloop

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Only Antenna Rotator(s) I've seen that works WITHOUT the extra 3 or 4-wire cable is Eagle Aspen ROTR100 and 500065, which the usual sources indicate is OUT OF STOCK (Q: temporarily or forever???). You MIGHT find one on fleabay. Note that it requires AC Power connection in the Attic:
https://www.antennasdirect.com/cmss_...%20-%20PBI.pdf
http://www.summitsource.com/eagle-aspen-rotr100-hdtv-rotator-controller-cable-antenna-rotor-with-remote-automatic-outdoor-signal-aerial-position-mast-mount-locator-part-rotr100-p-6504.html
http://www.tigerdirect.com/applicati...YYPT-EAS500065

Alternatively, you can buy a conventional Rotator with IR Remote Control and install EVERYTHING except the R/C in the Attic, using an IR Extender (or IR Extender part of a Composite Video/Audio Extender pair)....but that means you can't SEE the front panel display or operate the unique front panel buttons and might have OTHER issues to deal with IN THE ATTIC from time to time....

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post #4798 of 4798 Old 06-24-2014, 04:31 PM
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holl_ands,

I'll take a look at all the links you suggested.

I need to do something. Everything was working fine for the last couple of years until about a month ago. Then WYCC (20) started freezing & the SS was varying all over & sometimes down to zero. It might be caused by the tree in front of the house but no other channel (that I watch) is affected. WYCC is the only channel that I watch coming from the Hancock Bldg which is only 2 degrees offset from the Sears/Willis tower. Maybe I am getting a multipath signal now or maybe I was only picking up a multipath signal before & now it’s gone.

The big old antenna in the attic was installed without a mast. It is held up at each end of the boom by a cord that is suspended between a couple roof supports. Sort of like a playground swing where the seat would be wrapped around one end of the boom to hold it from rotating. The only way I could adjust it was by hammering in a few more nails in order to swing the tail end of the boom around.

If I’m going to adjust an antenna it’s going to be something with a mast. And no sense using the old one because it’s got some real long elements which get in the way. Currently they’re not even properly snapped into place. They angle forward by about 30 degrees each because there is no room for them. The builders did a terrible job installing the antenna.

An antenna without VHF low band would be more compact & therefore give me more options for placement locations. And I'd use a mast.

Thanks again,
Mike
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