How to reduce our RX noise reception

or how to achieve Receiver bliss.

Let's start with the basics first.

Receiver gain setup

I always setup my receiver(s) with just enough attenuation/gain to make sure that the AGC only acts on the signal I'm listening too.
I have the preamps switched off on all band from 20m and above (14MHz and below). Depending on the band conditions I either use the build in attenuator or the RF-gain. This depends on the capabilities of the receiver however, my preference is to use the attenuator. Below are the steps which I use to achieve receiver bliss.
  • Record the S-meter reading of the band noise on a clear frequency. I.e., Tune away from the signal you are listening too and note the S-meter reading off the band noise alone.
  • Now apply attenuation until the S-meter reads as little as possible. (On the IC-7610 I can select the attenuation in steps of 3dB) A similar outcome can be achieved using RF-gain as well.
  • Next tune to the desired signal. The result is that the band noise will not stimulate the AGC into action i.e., the AGC will now only operate on the desired signal.
We now have selected the receiver sweet point for the current band conditions. The result is a very quite receiver which is very pleasant to listen to.
 

Receiver Noise Counter Measures

 

Quietening shack equipment

 

 

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