Hi folks, while looking at some circuits I started thinking (bad habit, I know
) and came out with the following idea, again, probably is stupid, yet I'd like to discuss it to find faults
First of all, let's state that the idea is to deal with "local" (in house or neighborhood) noise, that is, the one from SMPSUs, induction ovens, inverters, LED strips and then some; now, such noise is both "transmitted" along the power lines (be those domestic or outside a house) and, in some cases, radiated and ... picked up by our antenna, till now nothing new
Now let's think for a second to the so-called X-Phase "noise eliminator", for the ones unfamiliar with it, I'm referring to circuit like this one (just an example, you may find other similar units/schematics)
https://ok1tk.com/qrm-eliminator/ now, that unit uses a "noise probe" (noise antenna) meant to receive mostly noise, the noise from such an antenna is fed to a circuit which allows to shift its phase up to around 180° and to adjust its level, the result is then mixed with the signal received by the regular (true) antenna, at that point, by adjusting level and phase it is possible to cancel out ONE type of noise
Now, let's step back to the "line noise", let's say that we pick up the noise from the AC mains, for example we could use a 1KpF capacitor connected to the neutral of an AC wall plug, at this point, we do know that the "signal" on the AC line is on 60Hz (50Hz in EU), so we may consider whatever else we pick up as noise
At this point let's say we shift by 180° ALL that "noise" picked from the AC mains, adjust its level and mix it with the signal from the antenna, we should now achieve "local noise" (as said at the beginning) cancellation, won't us ?