Hi Chris,
the quality of the received signal it determined by it's SNR. So if you
have an antenna where QRM/QRN are at a higher level than the RX noise it
makes no sense to get a larger antenna (= produce more signal and
noise).
As QRM / QRN on 137kHz and even on 500kHz is rather high even with a
small antenna you will get more QRM / QRN and it will perform as well as a big
antenna.
So it seems absolutely normal to me that a small whip will performp as
well as a big wire antenna (for RX !).
More important that size might be other properties such as directivity
(eg with a loop you can null out a QSM source).
I do use my "big" TX antenna for RX, but do need to attenuate the signal
by at least 20dB to avoid RX overloading.
73, Rik ON7YD - OR7T
Hi Mal and LF,
Well, all I can say is that here the signal to
noise ratio on RX is better on my PA0RDT than it is on my long wire (inverted
'L'). I have always thought this a bit strange, quite often weak signals that
cannot be seen on the wire are perfectly copied on the PA0RDT. This applies
from 136kHz to 3.8MHz. I cannot see what else it can be other than local
noise/QRM level. 80m is another prime example where the noise has gradually
got worse over the years here.
Vy 73,
Chris, G4AYT, Whitstable,
Kent.
