Maybe I'm tired and confused because it's late, but how come when WGN signs off, WBBM must to? I'm obviously missing something here... What does them being close have to do with it? Paul ///// This would be neccesary only if one of the stations was working on their antenna system. According to the registered coordinates, these stations are about 2 miles from one another. When high power stations like these are that close together, each may induce enough RF into the other's antenna system to make it difficult to make proper adjustments. The "dark" antenna may even pick up enough RF to shock or burn personnel working on the antenna system. This is especially true with these particular stations since they are very close in frequency. The antenna systems at both stations are nearly resonant to the frequency of the other station.
As an example, here at KCKK tower #3 of the 4-tower system is not part of the daytime array. During the day it is connected to a detuning network making it invisible to the rest of the array. However, it is in between towers 2 and 4 which are radiating part of the 9.5 kw daytime pattern. Even though #3 is disconnected from the transmitter, it receives enough RF energy from the other nearby towers to place a considerable amount of current on the antenna components. I have personally verified that it picks up enough RF to make a human being jump backward several feet and shout an obscenity. I have a small burn scar on the top of my right index finger to remind me to be more careful even when working on "dead" antennas. Now here is an idea that Willis will appreciate. Remembering Tesla's idea for a wireless power distribution system, could one set up an antenna, tune it to the most powerful transmitter in your vicinity, and make use of the received power in your home? There is a lot of wasted RF floating around out there. Of course this would probably only work on analog signals. Maybe the power companies are the real backers of IBOC to prevent this from happening! That's my conspiracy theory. Patrick Griffith, Westminster CO Broadcast Technician NRC Broadcasting - Denver http://community.webtv.net/N0NNK/ http://community.webtv.net/AM-DXer/ _______________________________________________ IRCA mailing list [email protected] http://montreal.kotalampi.com/mailman/listinfo/irca Opinions expressed in messages on this mailing list are those of the original contributors and do not necessarily reflect the opinion of the IRCA, its editors, publishing staff, or officers For more information: http://www.ircaonline.org To Post a message: [email protected]
