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I am an amatuer radio operator and have read these posts with interest with regards to reception in this area.I have been experimenting with different antennas in hopes of receiving PBS Digital.I live in what is probably the lowest spot in Kanata to boot.Well for the fun of it I tried an antenna I built called a Hentenna(popular in japan for 6 meters) which was cut for 162mhz(yes I know way off freq for pbs).However to my great surprise as of 2pm I am able to pick up all 3 digi channels with this antenna indoors on second floor.So now I guess maybe ill build one that closer resonates.Google the antenna design,pretty simple to make out of copper wire or as I did copper pipe.In short it looks like a loop shaped like a rectangle with feed points about an 1/8 of a wavelength in.its about 1 foot wide by 2.5 ft tall(for 162 mhz).Not sure if dx is good today but if its average this looks like a good antenna.Ive had fantastic results on 2 meters as this design is VERY broadbanded.

CHEERS...and good luck
David in Kanata
 

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I live in what is probably the lowest spot in Kanata to boot.Well for the fun of it I tried an antenna I built called a Hentenna(popular in japan for 6 meters) which was cut for 162mhz(yes I know way off freq for pbs).However to my great surprise as of 2pm I am able to pick up all 3 digi channels with this antenna indoors on second floor.
One of the lucky ones. It's mostly all location, location, location for WNPI-DT (PBS).

Here's the TVfool coverage for WNPI-DT in Ottawa-West through Kanata.



Anywhere with colour has a decent shot at it. My Bells Corners antenna is in one of the just barely non-white blocks above Stony Swamp in the picture. We get WNPI-DT here, but with practically no margin to spare.

Cheers
 

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Discussion Starter · #4 ·
Oh for sure!!
Location loaction always.Its always a crap shoot.You can never tell sometimes what will be good or bad even though maps may say otherwise.
The reception I am getting is very close to the mark,yesterday was getting pixalation mid afternoon.Other wise it has been holding.According to the map you posted im in a zone one up from white so there is hope for others in the same boat.I will make a new version of this antenna cut to frequency and mounted higher see how that performs.This antenna is HIGHLY directional and also easily detuned by metal objects or people so needs to be in the clear somewhat.

CHEERS
 

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HERE ARE SOME GOOD POINTS FOR THE HENTENNA
1. Good performance
2.5-3 dBd gain
Low angle radiation
* Total performance is equivalent to 2-3 element Yagi-uda antenna,
Wide band width
http://www.hamuniverse.com/hentenna.html
http://www.wa0itp.com/hentenna.html

So it's got great bandwidth, and can be constructed easily from copper plumbing pipe.

Not exactly in the G-H leagues for gain, but better than a simple folded dipole. Or so the experts say.

Cheers
 

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Discussion Starter · #6 ·
What Ive learned along the way with antenna building,NEVER take for gospel claims on performace db gain etc.....good or bad.Build and try is the best way and a lot of fun.you just never know :)
 

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A very interesting design and simple build. I like those alligator clips to adjust the feed and very impressive low SWR. A reflector should improve gain and directivity. It won't match the gain of a GH but construction simplicity is hard to beat.

sparky mtl
 

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This is one sweet little antenna. I just sized it for UHF. It is 10 3/4" by 3 9/16" with the feed point at 2 5/32" off the bottom. This will fit behind a small picture frame. Will see how well it works tonight.
 

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This will fit behind a small picture frame. Will see how well it works tonight
Yeah, they already sell those commercially, the picture frame antenna.

2.5-3 dBd gain
That would be 4.65-5.15 dbi, which is certainly a lot better than the common loops that used to come with TV sets. Put a mesh reflector behind it at the proper distance, and you may get close to 8 dbi, at least as the general rule of thumbs apply.
 

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Here are my test results:Not bad for 5% the area of a GH
Ch 14, 70 (GH90) Ch 21, 100 (GH100) Ch39, 60 (GH100) Ch41,80 (GH90) Ch43, 70 (GH90) Ch44, 80(GH100) Ch45,80(GH100) Ch58,60 (GH95)
Your test results may very.
 

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Heck, except for channels 39 and 58, it could do you very nicely Xauto.

Thats the thing with digital, unlike analog, massive super dupper overkill doesnt get you that much real life practical differences, unless youre a DXer.
 

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Wow! 30 ga - can't get much thinner wire than that. Previous experimenters with this antenna, at VHF freq, have recommended thin wire.

I use cardboard and some wood, as well, for the main supports on the indoor prototype versions of the antennas I have tried (bowtie and SBGH. I find it works very well - good performance and high satisfaction for very little $ investment.

The Hentenna is ideally suited to this approach. I plan to try aluminum foil on cardboard, as a refelctor and, make the reflector moveable, by hand, so I can determine the optimum spacing between driven element and reflector - it must be in the range of 5" or so. I'll just watch the signal strength meter and slide the reflector back and forth "tuning" the antenna for maximun strength.
 

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I have a board(3 7/8") that sits flat on two curtain rods, in the corner of the room. There are two screws in the edge, so that I can hang by two holes, the carboard. So the antenna on one side and the reflector off the other. The board give me a standard test bed.
 

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Discussion Starter · #17 ·
I will try and post a picture of what I built but it sounds like you guys already are running with this design to experiment with.My antenna is cut for about 162 mhz so im thinking this is allmost 3 wavelengths long for pbs etc.This could be why it still works.
I have also heard of some other Hams who have built reflectors and directors of the same to make a beam.Its a fun little antenna.As of this morning and past 3 days in my location at the start of the carp river in kanata Ive had pbs non stop with odd pixalation at times.
 

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it's make from about 30 gauge Ma bell type wire on cardboard.
?? Most of Ma Bell "solid" telephone wire is 24 gauge or better AFAIK. For 30 gauge you have to take apart small transformers or TV yokes etc, heh.

I have also heard of some other Hams who have built reflectors and directors of the same to make a beam.
Thats the beauty of the short wavelengths of UHF frequencies, its easy to make a solid or mesh reflector for it. At some ham frequencies, because of the size, it would be insanely impractical, heh.
 

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So if I were to make a Hentenna tuned for channel 6 (82-88 MHz), if my calculations are correct, it should be about 176.5 cm tall, 58.9 cm wide and the feed points should be 35.3 cm from the bottom. Now I will have to see if that will fit in my attic. ;)
 
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