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Old 5-Jul-2013, 4:35 AM   #35
Pete Higgins
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Join Date: Apr 2013
Location: California, 58 miles @112 degrees from Mt. Wilson
Posts: 83
tripelo,

Thats interesting, I assume you derived your measurement through empirical testing for channel 13? Winegard recommends optimum vertical stacking @ .94 wavelengths spacing and minimum @ .6 wavelengths for the lowest receive frequency of a broadband antenna. They published a chart for single channel antennas showing channel 7 @ 48, 8 @ 46, 9 @ 44.5, 10 @ 43.5, 11 @ 42.25, 12 @ 41 and 13 @ 40 or all at approximately .6 wavelengths.

Right now, its just the bare Radio Shack rotor & mast. So far that thing has taken everything Ive thrown at it, including the big Wilson Shooting Star for several years. My TV tower rotor is an NTE ECG U106 with a TB-105 thrust bearing ~ 2.5 above it. I had just ordered another TB-105 before I got your post. Great minds?

Boy, those things sure have gone up in price since I bought the first one a few years ago. I think I paid $17.50 + shipping and this one cost me $24.49, so with tax & shipping was $36.48.

Channel Master was one of the premier brands here from the mid 1950s through the late 70s or mid 80s, when it seemed like their antenna quality and customer service really declined. I think I bought my CM-4228 in 72 or 73 when I was stationed in Sacramento, CA. I also still have one of their 300 ohm dual input VHF/UHF antenna amps. with a 75 ohm output. The power supply has a 110 VAC cord and sends AC up the coax to the mast mounted pre-amp. I used its VHF input (through a 300/75 balun) with my FM Yagi up until last year. No idea what the model number is or its specs.
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