My original reply was "shooting from the hip". Dan. What is the frequency of the desired AM station? A half-wave dipole might be the answer if the desired station is towards the upper end of the AM band. Regardless, the "Radio Amateur's Handbook" is the de-facto bible for such things as antennas at MW and SW frequencies.
SoundChances, hehe..yes, KOMA at 1520 kHz has been quite the "blowtorch from the prairie" for many years. One of my long-time friends grew up in Barstow, CA before moving into the OKC area approx. 1974, and he was a regular listener of KOMA when he was a kid growing up in CA back in the 1960's. Sadly, KOMA (now KOKC) no longer runs a top-40/oldies format, but instead broadcasts ****.....errrr...... ultra-right-wing talk radio. When morons like Michael Savage rant about the Fox News network being "soft" and "liberal" in their news coverage, you KNOW you've wandered into the far-right!!!
Nevertheless, the three-tower array of KOMA/KOKC is a frequent thing I see when travelling south along I-35 through Moore, OK on my way to various clients in the "south 'burb" of Norman, OK" which is sort of a "miniature Austin, TX"...
http://www.fybush.com/sites/2004/site-040122.html
http://www.radio-locator.com/cgi-bin...=AM&service=AM
Bri