Rudy's latest article on small vertical efficiency for 600M, published this July, is very timely and reinforces some of the discussions we've had. Read and enjoy! _http://rudys.typepad.com/files/600m-verticals-part-2-1.pdf_ (http://rudys.typepad.com/files/600m-verticals-part-2-1.pdf) Paul, K5AF In a message dated 9/26/2012 9:27:01 A.M. Central Daylight Time, [email protected] writes:
>> I've used screens when I needed a wide bandwidth ground system, but never > under other conditions. > > Adding a screen or preferably, additional short radials at the base will > assist in stabilizing the resistance component of the vertical radiator > and capacitance across the base insulator as ground conditions change due > to wx, seasonal ground moisture, etc. The stabilization effect is > probably more important with directional systems than it is for > non-directional radiators and is common in AM broadcast systems where an > array is sited in a flood plane. > > Paul, W9AC A screen will result in much stronger radiated power where it is wanted if the antenna of any height is over poor ground. Carl KM1H _______________________________________________ UR RST IS ... ... ..9 QSB QSB - hw? BK _______________________________________________ UR RST IS ... ... ..9 QSB QSB - hw? BK
