> Yes and no. Most often NO. The FCC would require a power reduction in most cases. Have > you ever seen a Class 4 AM -- with a power like 833 watts Day and Night. ( I think the > 1400 Silverdale, WA has less than 1 KW ). That is because -- AM stations -- are like the > Educational FM stations. They are applied for with a "protected" and "interfering" > contours -- based on both the tower and ground system. Change the ground or tower -- the > power changes.
That almost always occurs when there is a significant change in the tower itself. Usually moving from a 1/4 wave tower to one significantly taller and more efficient. For example, many years ago then-WHIM-1110 went from a 1/4 wave tower to a 550 foot FM tower. They had to drop power to around 650 watts to keep the same groundwave coverage contour. > So adding any type of cable, wire or metal can "augment" the basic authorized contours. > As a Ham operator -- you can "tinker" with equipment. In Commercial use -- you can NOT > just add a wire here and a clamp there. In the old days -- but that was before there > were thousands of stations. I disagree. You can add all the copper you want as long as you do not materially alter the configuration stated in the license. If I wanted to add a 75' square screen to a station, I would not have to file a thing - as long as the base resistance was not changed. As a permanent change, going from a 120 radial buried system to a 6 wire elevated counterpoise system probably would require the appropriate form to be filed. That would change the license description. Years ago we added a copper strip between two towers in a directional system. Made no changes to any parameter, and we filed nothing. Some of this is just pragmatic. If it's buried and doesn't change the parameters, then why open a paperwork can of worms? Craig Healy Providence, RI _______________________________________________ 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]
