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GroundUrMast
14-Nov-2011, 7:41 PM
New member GLC privately asked for my assistance with posting their help request.

Custom building a tv antenna
I live in Tulsa, Oklahoma and currently have a large deep fringe Winegard and a large deep fringe Channelmaster antenna on my roof. I currently pick up the 29 Tulsa digital tv stations but have been trying for the last 3 years to reach out to the west/southwest to pick up the Oklahoma City tv stations which are 103 miles away from me and also the Joplin tv stations which are the same distance to the northeast of me. Once in a while when the tropispheric conditions are right I'll lock in NBC and FOX affiliates out of OKC, 4.1, 4.2 and 25.1, 25.2. Also, CBS affiliate out of Joplin, 7.1, 7.2. Basically, I am not engineering inclined at all and mathematically would not even begin to figure out how to use the TV Fool google maps for heights, distance. etc. I would like to know if you could figure out the stats from TV Fool.com for me to see if I could even reach the Oklahoma City and Joplin transmitter signals or if anything that you know could be done with your mathematical calculations to reach these distant transmitter signals. I am not into DXing. ... [do] you think that I could reach the transmitters from OKC and Joplin, or would you or could you suggest someone willing to custom build me an antenna with the amplifiers or whatever I need. ... Thanks!

... My specific street address of my residential home in Tulsa is: [edited] , zipcode 74134 I am presently using a TRUSPEC amplifier, Model number TA-25. The deep fringe antennas are five feet higher than the rooftop and approximated 60 feet off the ground in these one level homes. The antenna sights have no tree obstructions. If you have further questions, feel free to ask. You may send this along to others if you would like. Again, thanks!

25' AGL: http://www.tvfool.com/?option=com_wrapper&Itemid=29&q=id%3dec120e58765046
60' AGL: http://www.tvfool.com/?option=com_wrapper&Itemid=29&q=id%3dec127d5e619508
250' AGL: http://www.tvfool.com/?option=com_wrapper&Itemid=29&q=id%3dec128d879799d9

Oklahoma City Stations: http://www.rabbitears.info/market.php?request=station_search&callsign=KETA#station

Joplin Stations: http://www.rabbitears.info/market.php?request=station_search&callsign=KFJX#station

GroundUrMast
14-Nov-2011, 7:52 PM
I doubt reliable reception from Oklahoma City or Joplin would be possible even with construction of a tower in excess of 100'.

But, I wanted to give GLC the benefit of others thoughts and opinions.

be236
14-Nov-2011, 8:46 PM
How about getting a 91XG for those 2EDGE stations around -10 dB NM? I've gotten similar stations with those conditions, but not reliably (just occasionally) using a home built M4 and CM 4221.

GroundUrMast
14-Nov-2011, 10:14 PM
How about getting a 91XG for those 2EDGE stations around -10 dB NM? I've gotten similar stations with those conditions, but not reliably (just occasionally) using a home built M4 and CM 4221.

Which signals are you referring to specifically?

Dave Loudin
14-Nov-2011, 10:56 PM
@be236, I don't see that many stations with those NMs. Click on any of those stations in the list to get the path profile. Note that GLC is WAY below the radio horizon. It would take a lot of money and effort to chase those, and the results will be spotty at best.

be236
14-Nov-2011, 11:21 PM
How about COCO (real 7 , virt 5.1).. -10.7dB NM, 2EDGE?

I've been able to get a -12 dB NM 2EDGE occasionally and I'm 107 miles away from my towers using home-built M4 and CM 4221 (sometimes, yes, it's very spotty), but maybe a stronger antenna like a CM4228HD ( has low VHF able), might be able to get it? Or ganging up two CM4228HDs for a 2.5dB gain?

And yes, I would think it'd be spotty as well... so not sure if it's worth it or not to him.

Worse case scenario is that he's out $70 if it doesnt work?

Jammer
23-Nov-2011, 6:54 PM
be236 KOCO is listed as 2edge for the 25' height only and Tropo for 60' which may be the source of confusion. In essence there isn't a useful ridge to provide diffraction so he's only going to see tropospheric scatter:

http://www.tvfool.com/?option=com_wrapper&Itemid=29&q=id%3dec120e58765046%26t%3dALLTV%26n%3d28

I don't believe that any antenna will provide reliable reception of these stations at this site with reasonable antenna heights. As noted upthread, the stations are beyond the horizon.

If money were no object (as might be the case when constructing a CATV headend) then a tower could be built or a more favorable location (higher elevation) nearby selected. It's going to take hundreds of feet though.

be236
23-Nov-2011, 8:28 PM
Jammer, yeah, I agree with you.. at that distance, reception will be spotty at best.

I guess my point was.. if he really wanted those channels, it can't hurt (other than out $70) to get the best gain antenna and aim and hope for the best and hope to occasionally watch that channel.

Where I'm at... I have stations at 107miles out, 2EDGE, NMs -8 to -13 dB.. and with a homemade M4 (similar to CM 4221) I can pick up some channels from there once-in-awhile.. I guess it's better than nothing. (heh).

Tower Guy
24-Nov-2011, 3:31 PM
I doubt reliable reception from Oklahoma City or Joplin would be possible even with construction of a tower in excess of 100'.

But, I wanted to give GLC the benefit of others thoughts and opinions.

I have a 125' tower and it doesn't help me much.

The added difficulty in OK is the strong adjacent and co-channel stations.

If there was a particular station that was desired an antenna array for that one channel could be considered.