mark_aok,
Any 3-wire cable 22 gauge or thicker should work just fine for a 50’ – 100’ cable run. The lower the gauge #, the more current the wire will support and the lower the voltage drop across long runs (lower resistance). If there’s not much cost difference 20 gauge would be better than 22. Stranded wire is usually recommended (especially for outdoor installations) because it withstands flexing much better than solid conductor wire. For an attic installation, wind flexing won’t be an issue so even solid core doorbell wire would probably be OK. Doorbell or 5 or 7 conductor sprinkler valve control wire sold at Lowes & Home Depot would also be more than adequate for your needs. You can always double up on the strands if you have extra. Just make sure you match the colors you pair on each end.
I have an NTE/ECG U-106 3-wire rotor that I bought before I knew better. I bought the U-106 because the literature said “Digital display indicates antenna position during operation” & “Pre-set to 12 TV/FM station directions for automatic antenna positioning”. What I didn’t pick up on was that the bearing readout was a 2-digit display. North is 00 or 36, east is 09, south is 18 and west is 27. My street is aligned with True North and my house sits squarely on the lot facing east so visually it’s easy to determine array alignment. This might not be the case with your attic install. I would recommend having a signal strength or SNR meter to assist you with antenna alignment. I hope you don’t need it but even after a fresh calibration, manually turning my rotor to display “18” can have me pointing somewhere between ~175 & ~185. Fortunately, if you “bump align” for max SNR and memorize the location to a pushbutton it seems to return to that location –at least until the rotor goes out of calibration.
Like the AT-500, the U-106 is a three wire rotor that uses a timing circuit for calibration. 3-wire rotors use AC synchronous motors that run at a predictable speed, and the control box simply runs the motor for the amount of time needed to turn the antenna from where the controller thinks it is to where the controller wants it to be. Over time, the position error grows…
After moving it to “home” or 00 deg., basically, you rotate it full clockwise (360 deg.), hit a button labeled “Initial” and it memorizes the time it takes to return to 00 or “home”. Unfortunately, mine frequently requires recalibration. Since my signals come from four directions, it’s fairly easy to detect when it needs calibration because when I turn the array there is either nothing there or the signals are barely watchable. I probably have as much calibration mileage on the rotor as actual array turning mileage. Sometimes, when the calibration goes off, it won’t fully turn to a true 360 so to get it full clockwise you have to power off, power on with a “reset” turn some more and repeat the process until it visually has the array pointing north. I’ve since read that other folks are experiencing the same calibration issues with other brands of 3-wire rotors. I think AntennaCraft, Centronics, Channel Master, Magnavox, Philips, RCA, Stern and probably others sell this same design under their own labels. The AR-500 control box & rotor head look identical to my NTE/ECG U-106.
Please report back and let us know how yours works out.
