I have been following the discussion on ferrite receiving antennas - 
due to work pressures I am a few weeks behind in reading the mail.

The use of this type of antenna for LF amateur radio is not new. I 
used it successfully as a portable antenna on the old 73kHz band 
several years ago. 

I used the existing winding (LItz) an ordinary long-wave broadcast 
radio antenna. The rod was about 150mm long. The coil, tuned with a 
large fixed C and a variable C, formed the drain load of a 2N3819, 
with the output taken from the source. The selectivity was very high 
indeed (essential to reduce the huge commercial signal on the 73kHz 
band) and sensitivity was adequate to overcome the noise level of my 
very sensitive Datong LF converter.

The interesting thing was that Peter, G3LDO, tried to replicate this 
and had poorer results, perhaps indicating that not all long wave 
radios had ferrite that worked at 73kHz.

Mike, G3XDV
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