How Does It Work?
The basic QNC unit is a small box that is inserted in-line with the main antenna coax that comes from the main antenna to the amateur’s radio in the shack, with one small addition: it has an extra AUX Input.
This AUX antenna (“Noise Pickup Antenna”) is simply a length of wire 6 meters long, placed lower down to catch the local noise, if it is installed too high it will pick up the far away signals which is not what we want to reduce. The focus is on the local noise, thus a lower physical installation. I ran my own wire under the eaves of my house. </span></p><p><span>The QNC unit takes the AUX signal from the local Noise Pickup Antenna inverts it, and mixes it with the Main Antenna input. The result – which contains the wanted distant signal minus the unwanted local signal – is then sent to the amateur’s radio normal input.</span></p><p><span>By adjusting the mixing the local noise on the signal can be cancelled out almost completely. The level of cancelling can be adjusted over a wide range. The best situation is where all the local stations are cancelled out and only the far away stations are audible. But then you risk talking over the local Stations trying to contact the far stations. A bit of experimentation will be required to achieve the best operation! </span></p><p><span>During the last few months I found the unit especially useful to me working the HF bands.</span></p><p><span>The QNC currently works from 1Mhz to 30Mhz, and there are plans to expand the range from 1.5 MHz to 50 Mhz.</span></p>
<p>YouTube Link <a href=”https://youtu.be/r57JfHcZ6CY” target=”_blank” title=”QRN Noise Cancellor”>QRN In Action</a></p>