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For Ch6 (ONLY), AWG12 will do the job in a Folded Dipole:
http://imageevent.com/holl_ands/loops/folded
Thicker tubing is needed if you also want Ch5 & FM Band.
Thanks holl_ands! The sharp decline above and below channel 6 would actually be useful. Would using AWG14 be even better for that, or would it likely cause too much loss at 82 and 88 MHz?

Separation distance can be whatever is convenient....such as
wrapping around a piece of 1-in PVC....or bigger as in mlord's:
http://www.digitalhome.ca/forum/showthread.php?p=833571
For an indoor install, would wrapping it around wood be OK, or would the water content of the wood cause problems?

One other question, how apart should the two ends be? Thanks again for the great advice!
 

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(WNPI hovers around 0 NM with a decent elevation, which makes WNYF doable in a pinch at -10 dB NM.)
I am VERY interested in knowing WHAT antenna is going to overcome -10 dbM NM for STABLE digital reception, assuming second edge...:eek:

I and many others have difficulty pulling in anything digital below +5 dBM, 2nd edge, and thats with bare minimum setup losses - am i missing out on the secret ;)
 

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For an indoor install, would wrapping it around wood be OK, or would the water content of the wood cause problems?
It would depend on where indoors. Indoors in a room, its generally very dry. In an attic, you can still get moisture, so it would be advisable to mount/hang it with styrofoam blocks. (cheap enough, heh)
 

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Discussion Starter #44
For an indoor install, would wrapping it around wood be OK, or would the water content of the wood cause problems?
Something hollow would be best, as the models and such assume air as a spacer.

But I would certainly try it with wood: just put some electrical tape between the wire and the wood.

Besides, "dry" wood, especially softwood, consists of a heck of a lot of air.

Cheers
 

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CH 52 Antenna

Hey Guys !


What do you Guys think about a CH 52 yagi?

With 12 dB gain, I get a yagi of 42 inches with 8 elements with K7MEM calculations.


I get this warning on his calculator:

Warning: Boom Diameter is too large. The Diameter of a Metallic Boom should be less than 1.015 (1-1/64")

Thanks,

Intravino
 

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Discussion Starter #46
What do you Guys think about a CH 52 yagi?
That should be doable. Do you want to come here for the party? ;)

I get this warning on his calculator: [boom diameter too large]
Use a non-metal boom instead, or switch to 1" diameter aluminium tubing for the boom.

We can probably improve the output from K7MEM by running it through some simulation / optimization software before the build.
 

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empty factory in Ottawa

We could rent LandsDowne park and use the cattle castle or inflatoe dome to create multiple yagis.

What will the locals think? A Yagi fest ?

either channels 23 or 65 works for me :rolleyes:

then again if we could build one giant yagi array and send the signal down the internet to all who want it using some form of a streaming packet --- the CRTC would be hot on our tails !! free rebroadcast ( pirate ? ) tv
 

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I live east of Ottawa and would be interested. I have yet to build my own antenna and would be interested in learning and supplying some labour/materials.
 

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Thanks holl_ands! The sharp decline above and below channel 6 would actually be useful. Would using AWG14 be even better for that, or would it likely cause too much loss at 82 and 88 MHz?



For an indoor install, would wrapping it around wood be OK, or would the water content of the wood cause problems?

One other question, how apart should the two ends be? Thanks again for the great advice!
As shown in the charts for Hi-VHF, it takes quite a big change in wire size to see much of an effect.
AWG14 will be nearly the SAME as AWG12 on Ch6. You can try it yourself, I just added the Ch6 AWG12
4nec2 file to my Folded Dipole Album.

Wood will suck up some of the energy (off hand, don't know how much...and it would get WORSE as
it sucks up more moisture). Wood also complicates the calculation of dimensions because it affects
the velocity factor (off hand, don't know how much, and will ALSO change as it sucks up moisture).
Perhaps some research would yield a guestimate....And Attic would be much better than outdoors...

I would stick to PVC, since most of the separation between wires would be AIR.

Quasi-optimum separation between Folded Dipole elements should be 0.5 to 1.0-in for AWG12-14.
The Feedpoint Gap isn't in the 4nec2 model, so I don't have any data wrt optimum value,
but based on other VHF antennas, I would guess it's about 0.75-in.
 

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Thanks holl_ands! Now it is just a matter of getting some PVC and finding the time to make this. I will certainly let everyone know how it works out.
 

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Tin Lee filters, ch24 and ch11

Hi,

At the build party I can bring some Tin Lee filters for channel 11 and 24. They need a new Ottawa home.

Thanks.
 

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WNPI optimized antenna

Hi mlord,

Do you think it is feasible to make an optimized antenna to pull in WNPI? That would be top on my list.

Thanks.
 

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Discussion Starter #55
On a related note (and, Stampeder: please do not move this post!)..

I wonder what the interest might be in an Ottawa MythTV-0.22 install party for O.T.A. use, early in the New Year ?

I have to set up one system for a friend already, and might even do another system for myself. So.. what the heck.. any one else wanting to make the plunge?

We could even form a support group, to grieve amongst ourselves about low WAFs and the like, and help each other out with fixes for stuff. ;)

Or not.

O.T.A. only, though -- I don't do pay TV here.

Cheers
 

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Hi mlord,

I'd be interested. I'm already up and running with MythTV 0.22 with 4 tuners. I could help out and I'm sure I would learn from how other people set things up and what hardware they use.

Thanks.
 

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Discussion Starter #57
I'd be interested. I'm already up and running with MythTV 0.22 with 4 tuners..
Now that's cool (I only have 6 tuners here, plus one spare).

You & I oughta meet up regardless. How do your tuners relate to antennas (this being an O.T.A. subforum)?

-ml
 

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I wonder what the interest might be in an Ottawa MythTV-0.22 install party for O.T.A. use, early in the New Year ?
I would also be very interested (as I posted here, I am currently setting up MythTV), though things will be extremely busy in the new year so I will have to see if I can make it or not.
 

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What distro are you guys all using for Mythtv? I played with mythbuntu, also built Mythtv for an old Xandros distro also a couple years ago. I have a pvr-250, but I don't have an ATSC tuner for the computer yet, but would like to go this route.

Bruce
 

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I'm guessing mlord has MythTV 0.22 source code builds in mind or maybe SVN builds, so If that's the case then the distro won't matter. :)
 
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