Hi Tod. I built this cct many years ago and found it unsatisfactory
compared to the noise blanker in my receiver. It requires a high level of
power line noise spikes on the power line coming into your shack before it
will trigger the blanker diodes and that caused a lot of IMD. Put a scope
on your 110 V line into you QTH and see if you can see any power line spikes
on your 110 volt line. If not the noise you are receiving may be quite some
distance away some your QTH being radiated instead of induced along the AC
line into you shack.
Of course the best solution is locate the power line noise source and try to
get it fixed.
The next best solution is a noise canceller which is inserted between the
receiver and the receive antenna and it doesn't cause IMD.
Markus VE7CA
--
Markus Hansen
VE7CA, North Vancouver, BC CANADA
Web site: http://www.shelbrook.com/~ve7ca/
On Tue, Nov 24, 2009 at 11:48 AM, Tod - ID <tod@k0to.us> wrote:
> For some folks on 160 noise reduction is of interest.
>
> I have placed a copy of a paper written for the LowDown [A LowFer magazine
> which I believe is no longer being published] some years ago, It used to be
> in the LowFer library but seems to no longer be available online.
>
> The paper was written by John Reed and has the title "Synchronous Noise
> Blankers Revisited". I have placed a .pdf copy of it on my web site at
>
>
> http://www.k0to.us/HAM/Articles/Synchronous%20Noise%20Blankers%20Revisted.pd
> f<http://www.k0to.us/HAM/Articles/Synchronous%20Noise%20Blankers%20Revisted.pd%0Af>
>
> If anyone has built and tested this circuit I would appreciate hearing from
> them. I am planning to fabricate one for myself and test it to see if the
> claim of 60 to 80 dB of noise reduction is real.
>
> Tod, K0TO
>
>
> _______________________________________________
> 160 meters is a serious band, it should be treated with respect. - TF4M
>
_______________________________________________
160 meters is a serious band, it should be treated with respect. - TF4M
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