Re: LF: USA issued 68 to 76 kHz band with 10 W ERP

[Warren Ziegler <wd2xgj@gmail.com>]

Markus, Stefan, LF,

      Please keep in mind that 10W represents an upper limit, we are free to run anything below that!

     About Quadcopters - the limitation is the life of the battery - which is on the order of 15 minutes, even if it could lift enough weight, it wouldn't last long! (The more weight it must lift the higher the battery drain!)

     A better solution might be a remote controlled airship (zeppelin) where the helium supplies the lift and motors provide steering only.

73 Warren K2ORS

  

On Sun, Aug 4, 2013 at 7:39 AM, Stefan Schäfer <Stefan.Schaefer@iup.uni-heidelberg.de> wrote:

Hi Markus,

Am 04.08.2013 09:46, schrieb Markus Vester:

 

Stefan, 10 W ERP is not that hard - anyone who can radiate 80 W ERP on 136 will be able to do 10 W on half the frequency ;-))

Oh yes indeed. The radiation resistance of the wire is about 1/4 and the needed L is about 4x, so the coil losses will be 4x higher too. The ground losses may drop a bit. Then it depends on the ratio of coil losses to ground losses. So 80W is realistic :-)

I don't know anything about LF propagation on that band. Is it much different to 2200m? And what are the distance records?

Yesterday night a friend showed me his new GPS-stabilized quadrocopter. It's stunning how it could just about be parked in midair, despite some lateral winds. Seems that would make a great antenna carrier! Not all of the neighbour's seemed to enjoy it as much as we did...

MOST interesting! Did you ask him what the weight can be lifted? And will it still be stable then? Is it expensive? Do you fear some EMC problems? (The topic should be discussed in a new subject then)

73, Stefan/DK7FC

 

Best 73,

Markus (DF6NM)

--
73 Warren K2ORS
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