Topband: 160m Noise Level

[Michael Tope]

I don't believe that is necessarily true, Roger. If the noise it truly 
omni-directional, a directional receive antenna can still increase SNR 
because it increases the amount of signal captured compared to the 
amount of noise captured. The reason for this is that for 
omni-directional noise, the increase in directivity robs Peter to pay 
Paul, so the total noise power received remains constant whereas the 
increased directivity (assuming it is in the direction of the desired 
signal) increases the desired signal power received.

OTOH, if you have a dominant noise source in the direction of the 
desired signal, you are out of luck unless you can take advantage of 
difference in polarization the way that N4IS does with his horizontal 
waller flag.

73, Mike W4EF.....................

On 11/27/2024 1:44 PM, Roger Kennedy wrote:
> However, the general noise level EVERYWHERE here in Britain is around S7
> these days - that's on 160m 80m & 40m. That's in an SSB Bandwidth, and with
> an accurate S Meter. And because the noise comes from every direction, no
> phasing unit or directional receiving aerial will help reduce it.