Puzzler

[steambender]

Zippyt

Steel mills often have electric arc furnaces...really, really noisy for shortwave radio users. Power generators are also very noisy. Without knowing, I'd guess that your line of sight link runs at a higher frequency that would only be bothered occasionally.

Last time I checked, the wireless remote fobs for cars were far enough away frequency wise, that Starbucks Wifi wouldn't interfere. Next time you go over for take-out Wolf, look at the rooftops for radio antennas. Or, if there's a Cell tower there, there may be some other lower frequency teansmit antennas on it. Zoning comittees make putting up a tower such a PITA that everyone piles on (for a fee) if there is available tower space. It's a valuable commodity.

steambender