On Fri, 18 Sep 2009 09:59:46 -0400, Paul Christensen wrote: >As I recall, harmonic energy in Part 73 AM broadcast services still falls >under the general emission limitations under Section 73.44(b):
Yes. Several things are at play here. First, when a transmitter is producing strong harmonic content, something is WRONG. It's either broken or mistuned. Second, we have the effects of the deregulation of broadcast engineering of the Reagan years (remmeber the rants against big government and for untrammelled free enterprise?), so the requirements that stations have licensed engineers on duty are long gone, and the FCC lacks the staff and funding to do much of its work still mandated by its own rules. Nowadays, a single broadcast engineer is likely to be responsible for a half dozen or more stations, even in major markets. Contrast this with 30 years ago when many major market stations employed 3 or more full time engineers, most of them competent to do transmitter work. For 20 years, I lived within 4 miles of virtually all the FM and TV broadcasters in Chicago, and had a gain antenna on the roof that fed a vintage Technics ST9030 FM tuner with a rock solid analog front end that had a four-gang tuning capacitor. Only once did I hear a spur from any of those stations, it was during an overnight maintenance period, and it was gone in a few hours. If you monitor the topband reflector (160M), you'll occasionally see posts about broadcast spurs on 160M, sometimes strong. It rarely takes more than a few weeks for pressure from hams on the FCC and those stations to clean up their act. The key words to the station are "something in your transmitter is broken, and is likely to fail completely. You should fix it soon before it takes you off the air and you lose advertising revenue." 73, Jim Brown K9YC ______________________________________________________________ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:[email protected] This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html
