[OKDXA] Speaking Of Digital DX...

[Nelson Derks]

Got the bug this past week to follow through on a project I've been 
meaning to get a round tuit for a while... Put up a one size fits all 
wire in the attic to cover TV & FM. Normally this would be a bad time of 
year to stroll around in the attic, but the attic fan has become a 
little squeaky and since it needs to be oiled that's two birds on the 
same perspiration.

In any case, visualize 64 inches of wire cut 16 inches from one end. 
Direct feed to 75 Ohm coax with the shorter wire on the shield, longer 
wire on the center conductor, tied as high as I could reach near the 
south end of the house. Basic concept is a full wave dipole on TV 
channel 7, approximately a half wave on FM and multiple waves on UHF. If 
someone wanted to do this for FM BCB the magic numbers would be 10 feet 
of wire tip-to-tip with the feedpoint at 2.5 feet.

We're talking zero gain omni. As we all know a proper TV antenna has 
gain and is directional so the wire idea is a poor choice... Except that 
I'm on top of a slight ridge and have always had good luck on VHF / UHF 
and with TV stations coming in from approximately 270 degrees around the 
compass I'm thinking w-i-d-e area coverage.

In the living room I have a Scientific Atlanta two-port drop amp with 
+11dB of gain on each side followed by an 8 dB Blonder-Tongue tap. At 
the moment I'm driving two DTV boxes and an FM stereo receiver with a 
second FM receiver to be added later. Normally I don't like using an amp 
on a broadband antenna cuz' there's always a paging system or strong FM 
just begging to create some overload or intermod issues but so far "no 
prob". If I was driving only one DTV box the amp would be a waste of 
resources.

On the FM side I'm hearing full quieting on all three LPFM translators 
in Tulsa plus the more ambitious stations in OKC, Fayetteville, 
Bartlesville, etc. On the TV side I have solid copy on all stations in 
the Tulsa metro along with 35 in Claremore, 17 in Bartlesville plus two 
LP signals on 40 and 51. Let's just say that if I was a fan of 
faith-based TV I'd have more than I could ever want...

This morning I'm watching the morning news on KFSM in Ft. Smith and have 
mostly solid copy on KOCB in OKC. KOKH is also trying hard but with a 
bit less moxie than 34. It should also be noted that the roof is wet and 
as best I can tell this isn't exactly a band opening kinda' thing but 
more like VHF / UHF stretching out in the heat & humidity of a summer 
morning.

Not bad for some scrap wire & coax no more than 15' above ground, ehhhh?
 
If I pull the drop amp and go full passive it still works FB on the 
locals but I will see dropouts on 35 in Claremore. 17 in Bartlesville is 
solid copy without the amp but it's something of a cheater signal. The 
stick is snug up against the Washington county line so it's not as DX as 
the license would suggest.

Cool thing about DX'ing DTV is that the weaker signals look just as good 
as the locals... When they don't stutter. ;)