Quote:
Originally Posted by Tower Guy
I'd suggest that the problem is a combination of a weak signal and interference from KOAM.
Your pair of Y1713s can be stacked horizontally about 34" apart to null KOAM and still add 2-3 db to KQTV. http://www.hdtvprimer.com/ANTENNAS/ganging.html
When combined with a CC7870 they will add by about 2 db. If this arrangement works your problem is interference. If not, you'll need more antenna gain. |
When I crunch the numbers, I come up with 31 1/8" boom to parallel boom to null KOAM. Logarithmic center frequency of CH-7 = 176.975 MHz so 1/2 wave length = 33.34618". Relative angle of KOAM vs KQTV = 111°... 33.34618" * COS(111-90) = about 31 1/8". If you are building a Horizontal stack, just be sure you can adjust the boom to boom dimension a bit either way.
If you want to field build a balanced open wire line combining harness, here is a table for various wire gauges.
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If the well is dry and you don't see rain on the horizon, you'll need to dig the hole deeper. (If the antenna can't get the job done, an amp won't fix it.)
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Last edited by GroundUrMast; 4-May-2011 at 6:56 AM.
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