Re: LF: RX Frame Aerial for 136kc/s - still experimenting.....

["jannsen" <0482183881-0001@t-online.de>]

jan-martin.noding@telenor.com schrieb:
> Hi
>
> still experimenting with frame antenna for 136kHz. The attached drawing (20kB)
> shows almost how it would have been made today, somewhat different from 
> the actual antenna.
> Experienced that it was no need for amplifier for a loop for 80m reception
> (used to avoid electrical noise from the open power lines), 
> and now also experienced that an amplifier did not improve reception for my 
> 136kHz aerial,
> the coupling has 1/100 area of the whole frame, seems to work for 50 ohm,
> the tuning range seems to be somewhat too small, need somewhat increased
> capacitance in cold weather, but it is low enough for rain.
>
> The S/N ratio is almost the same with the coupling loop as for high impedance
> amplifier connected to the end of capacitance.
>
> The aerial has been tested in +10°C....-2°C
>
> Signal strength last night for DCF39 was 80-150µV (-75...-80dBU) 
>
> Not sure if it is still a point to ground the center of the tuned loop.
>
> 73
>
> Jan_Martin
> LA8AK@online.no (WW.Loc: JO38XC)
> N4623-Kristiansand (tel.: +47-380-87178)
> http://www.laud.no/la6nca/la8ak/ 
Hi Jan-Martin,

I have experimented with the BB130 tuning my loop (70m long, 12m high 
and 2m above ground with two windings). did receive signs from mf band 
(BC) nothing else. every thing was ok after changing the BB130 by remotely
tuned variable capacitor.

regards
Uwe/dj8wx