[Elecraft] Noise Blanker

[N2EY at aol.com]

In a message dated 10/2/06 10:45:35 AM Eastern Daylight Time, 
rondec at easystreet.com writes:


> Yep, that's why I also wrote in the message you quoted from: 
> 
> "Such trucks often make a lot of hash from various electric motors, etc. -
> just the sort of thing the NB can't touch. "

Agreed!

My only real point was that the electronic injectors can make noise similar 
to an ignition system. 

OTOH, a diesel like this one:

http://people.bath.ac.uk/ccsshb/12cyl/


> 
> My NB works FB, but is by far does the most spectacular job on
> high-amplitude short-duration pulses like ignition noise and cheap lamp
> dimmers. That QRN just disappears when the NB is turned on even though it
> may be blanketing all signals without the NB. 
> 
> Most other QRN sources helped very little or not at all by the NB in my
> experience. That would include most of the QRN coming from non-ignition
> sources in large vehicles. 
> 

> Have you had success in dealing with those sorts of QRN using the NB, Jim?
> I know there're some mods folks have made to the NB but I haven't tried
> them. Other that cheap lamp dimmers that appear from time to time, I live in
> a very quiet QTH, fortunately! 

In my limited experience, the only type of noise that blankers and limiters 
help is exactly the type you describe - high-amplitude, short-duration pulses.  
Other types of noise, by their very nature, cannot be helped by a blanker or 
limiter. 

I think there's a lot of confusion on the subject of "noise", because the 
word lumps together all sorts of QRN with very different characteristics.

73 de Jim, N2EY

also pretty lucky in the QTH