Re: LF: Activity from DLF´s 360m mast

["Rik Strobbe" <rik.strobbe@fys.kuleuven.ac.be>]

At 11:17 18/07/2002 +0200, PA0SE wrote:
> Dear Walter and the
> LF-gang,
>
> Assuming the 360m mast has no top load my antenna simulation program
> gives a feedpoint impedance of
> Z = 11.9 - j149 ohm over perfect ground. The reactive part depends on the
> diameter of the mast of course which I have arbitrarily put  at
> 3m.
> Be sure to measure the current into the mast so the EMRP can be
> calculated.

quite impressing ...
That would mean than no more than 214mA antenna current would be needed
to get 1W ERP. If the antenna has a +/- 50% efficiency that would mean
that about 1.1W input power will do the job. The overall gain of the
antenna system would be close to 0dBd, that would be 30 to 35dB better
than most ham antennas. 
A ham signal from the Frankfurt area is S8 with me (using a calibrated
s-meter), so I guess that running a few 100W into the monster will
produce S9+30dB, a nice signal but still no more than 1.6mV into 50 Ohm
(I'm afraid to little to burn a lamp)
The other way arround : taking into account that 1mW ERP is sufficient to
get a good QRSS signal over most of Europe it would have been interesting
to run just 1mW into the big antenna during one night (in winter) a see
how far that travels. A pitty that the activity will be just a few
hours.

73, Rik  ON7YD