Comparing performance off different Receivers on very weak signals

In this page I want to show the performance from different Receivers in ability to receive and show very weak signals

I want to compare the following available receivers

Demodulated signal and Spectrum display and/or Waterfall

Spectravue and funcube dongle



Perseus SDR

Only demodulated signal

Kenwood TS2000

Kenwood TS870


Yeasu FT736



Demodulated signal and Spectrum display or Waterfall

In my weak signal experiments and when I was working Aircraft Scatter I found that using a well performing Spectrum display combined with a waterfall it was possible to clearly see very weak signals still too weak to copy or even be audible. In using a funcube dongle and Spectravue with settings optimised for showing very weak signals I could see signals well before I could hear them

In the next part I will show the spectrum display off different receivers with signals signal to noise levels off :
4dB@12 Hz  = -20dB@3KHz
6dB@12 Hz  = -18dB@3KHz
8dB@12 Hz  = -16dB@3KHz
10dB@12 Hz  = -14dB@3KHz

To be sure that I don't get differences in results caused by the different frontends I am using a high input level at the receiver frontend so that the noise floor from the signals I generated are at least 20 dB above the receivers own noise floor

 First off all my performance using Spectravue and a funcube dongle

All these Spectravue pictures have been made using an FFT Ave of 5 and 12Hz resolution bandwidth

4dB@12 Hz  = -20dB@3KHz

6dB@12 Hz  = -18dB@3KHz

8dB@12 Hz  = -16dB@3KHz

10dB@12 Hz  = -14dB@3KHz

performance using Icom IC7300