Canadian TV, Computing and Home Theatre Forums banner

1 - 4 of 4 Posts

·
Registered
Joined
·
2 Posts
Discussion Starter #1
Hi, I'm a newbie but want to build one of these http://www.jedsoft.org/fun/antennas/dtv/gapless.html . If I understand correctly, the dimensions/location of the driven elements and reflectors are optimized for the diameter of the elements/reflectors. My question concerns how to determine the dimension/placement of the elements/reflectors for a smaller diameter material. I would like to use 1/8" or 3/16" ER4043 aluminum rod for both the driven elements and reflector rods (or maybe 1/8" driven and 3/16" for the reflector). How can I determine if this will produce a workable antenna solution and what the specific dimensions should be for the elements/reflectors? Do I need to run a model like NEC-2 , or is there a rule-of-thumb that will help me get started?

At this time, I am only interested in the stations near Hockessin, DE that
are along the 53 deg radial (as they represent all of the networks, are relatively close, and I'm hoping will all come in without adjustment to antennas rotation):

http://www.tvfool.com/?option=com_wrapper&Itemid=29&q=id=c77a72d35af4a9

Thanks for any help!
Gregg G.
 

·
Registered
Joined
·
7,360 Posts
You must be in a valley. No matter what antenna, you should tilt the antenna up to aim for the top of the hill thats in front of you at 53 degrees (65 degrees magnetic).

Im puzzled why you would want to build that particular uhf only model. Your channel 12 PBS is on vhf-hi.

I would suggest one of these GH with NARODs and 3 NAROD reflectors for UHF/VHF-hi.
http://clients.teksavvy.com/~nickm/gh_n3_uV.html

Theres a decent chance you may also get vhf-low channel 6 WPVI with it.

I would like to use 1/8" or 3/16" ER4043 aluminum rod for both the driven elements and reflector rods
1/8" is about 3.25mm or 8 gauge.

3/16" is about 4.75mm or 5 gauge.

ER4043 Aluminum is Tig/Gas Filler Rod. Check out how well it bends. Some aluminums will break when bent 90 degrees.
 

·
Registered
Joined
·
4,935 Posts
yeah definitely ur gonna want some VHF-HI, so go with one of the ones 300 ohm points out. Wouldn't worry too much about the wire size though. Go ahead and use what u have available, see what happens. The basic GH designs are fairly forgiving (except for maybe that Narod Placement, which is probly touchy). Just remember to read the tips about straightening wire, before ya build the elements.

PS - I used #8 AWG solid copper ground wire from Home Depot. Just have to strip it. Then straighten using the drill trick.
 

·
Registered
Joined
·
2 Posts
Discussion Starter #4 (Edited by Moderator)
Thanks for the info 300ohm and majortom!
Im puzzled why you would want to build that particular uhf only model. Your channel 12 PBS is on vhf-hi.
Mostly because I didn't realize which channels were vhf-hi (below 14, is that right?, real/virt has me confused as well)!

I'll do some more research and study your suggestions about Narods.

Great site!
 
1 - 4 of 4 Posts
Top