LF: Long range Reception
Wed, 17 Nov 1999 07:43:38 -0500
Walter Blanchard wrote:
> Couple of points re recent emails:
> E-field probes:
> If you have or make an e-field probe antenna you will find that sticking it
> on top of a high mast makes an enormous difference to the signal strength.
> I have one for Decca (70-127 kHz) and another for DGPS (300 KHz). Both are
> sticks about a foot long with low-noise pre-amps built in. By putting them
> on top of my 60 ft mast I added something like 30 dB to signal strengths
> and they produced signals not far short of what I get from my Top Band
> dipole strapped as a T-top. The reason is the concentration of the E-field
> around the top of a grounded metal mast and thus a considerable increase in
> effective height. It does not work with H-field (loop) antennas.
> Northerly propagation:
> The last few weeks reception of northerly DGPS stations (300 kHz) up to
> 2000 kms away has been excellent in the late evenings. Stations in Iceland;
> Sweden and Finland have been very good from about 1700 up to 0200. On one
> day I got continuous reception from Iceland (2000 kms) for almost 26 hours
> including daylight. However, normally they fade out about 0200 and are
> very patchy from then on until 0600 when they go completely. This is quite
> different from last year when they came in at 2300 and lasted until 0900 or
> even 1000 next morning. Propagation from the Meditteranean is nothing like
> as good. How this reads across to 136 I'm not sure but there you are for
> what it's worth!
> Walter G3JKV.
> Walter Blanchard
> Phone and Fax 01306 884359
> Dorking, Surrey
> RH4 2AN