[Lowfer] Noise Canceler Effectiveness... How it REALLY works

[Bill Ashlock]

Gentlemen:
 
After reading the description of the VK5BR noise cancelling circuit it appears to me this is nothing more than the old trick of combining the figure "8" pattern from a loop antenna and the circular pattern from a long wire antenna to form a cardioid pattern. If the amplitude and phase of these signals are properly adjusted the cardioid can have a noise-reducing null of at least 30db. A separate receiver connected to each antenna could be also used along with the proper amplitude and phasing adjustment to do the same thing. BTW the popular K9AY antenna uses exactly the same principle by introducing a controlled E field distortion to the normal figure "8" pattern that this antenna would normally have.
 
Bill Ashlock    
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