Topband: Any Linrad selective limiter noise blanker experts here?

[Richard (Rick) Karlquist]

The Kalman filter still generates a blanking pulse like the conventional
circuit.  Feedback loops adjust the width and timing of the blanking
pulse.  "Amplitude" is not applicable.  The frequency of the blanking
pulse is supplied from the power line in the shack (EG 60 Hz).  The
feedback loops average over many pulses and therefore suppress QRM
since it averages out in the long run.

Again, this was all published many years ago.

Rick N6RK

On 1/21/2020 10:30 AM, Jim Brown wrote:
> On 1/20/2020 2:28 PM, Richard (Rick) Karlquist wrote:
>> In most cases, line noise is a repeating function with a frequency of
>> 50 or 60 Hz.  To make an  effective noise blanker in a contest, you
>> simply have to make a filter that only responds to harmonics of the
>> line frequency and then generate the inverse function from a 50 or
>> 60 Hz line clock.
> 
> Unfortunately, that's too simple. For effective cancellation, that 
> inverse function must be precisely in phase (degrees, not polarity) and 
> equal in amplitude at each harmonic frequency.
> 
> 73, Jim K9YC
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