[Elecraft] Noise Blankers

[Jim Brown]

On 9/3/2017 9:18 AM, K9MA wrote:
> I have never found the K3 noise blanker to be effective.
<SNIP>

> BTW, the K3 noise blanker uses a filter with a bandwidth of about 100 kHz.
<SNIP>

The K3 NB is really TWO blankers, operating in two different IFs. Each 
can be tweaked for various kinds of noise from the menu system.  Access 
the menu by a Long Push of the NB button.

It's important to understand that there are many kinds of noise. Noise 
blankers are most effective on IMPULSE NOISE, which is the result of 
something arcing, usually in the power system, but also electric fences 
and neon signs.

Most of the residential noise we hear today is ELECTRONIC noise, 
generated by switch-mode power supplies and microprocessors.  Noise 
blankers must be very different to suppress this sort of noise. The menu 
tweaks provided by the K3, K3S, KX3, and KX2 are very critical to making 
the NB effective on the noise you're experiencing. One size does NOT fit 
all.

73, Jim K9YC

>> On Sep 3, 2017, at 10:37 AM, Rick Tavan<rick at tavan.com>  wrote:
>>
>> Noise blankers are difficult to design and to use. They work by blanking
>> out the receiver during noise pulses. The user defines what is a noise
>> pulse and how aggressively to blank it by adjusting the NB parameters.