[Elecraft] K2 noise blanker

[Brett Gazdzinski]

I did this mod last night.
I did not notice much if any difference.
I have to try the screwdriver on the transistor test Don told me about.

Since they fixed the streetlight, I don't have much noise, but have found 
noise that sounds
very like ignition noise from a car, with no impact from the NB on it.

No big deal, since I don't have a lot of noise (now).

Brett
N2DTS

----- Original Message ----- 
From: "Joe Planisky" <jplan at jeffnet.org>
To: "Brett Gazdzinski" <Brett.gazdzinski at verizon.net>
Cc: <elecraft at mailman.qth.net>
Sent: Sunday, March 01, 2009 6:03 PM
Subject: Re: [Elecraft] K2 noise blanker


> Hi Brett,
>
> Last summer, I had similar questions about the KNB2 in my K2.  In my 
> case, a neighbor had put up a new electric fence and I was getting QRM  in 
> the form of a pulse every second.  The unmodified KNB2 seemed to  have 
> little to no effect on the noise.  In fact, I questioned whether  it was 
> working at all.  A 'scrape test' (connecting a wire to the  antenna 
> connector and scraping it on some metal surface in the shack  to generate 
> static) indicated that it was indeed working.
>
> The modification described here
>
> http://www.dl7maj.de/KNB2-Mod.pdf
>
> seemed to improve the situation.  After making the mod described, the 
> KNB2 would partially take out the electric fence noise using the LEVEL 
> LOW threshold.  Not perfect, but better than it was.
>
> You can read the original thread by searching the list archives for  the 
> topic "[K2] KNB2 vs. electric fence" that started on August 3, 2008.
>
> 73
> --
> Joe KB8AP
>
>
> On Mar 1, 2009, at 2:18 PM, Brett Gazdzinski wrote:
>
>> I have tried it on various types of noises, some which sounded like  auto
>> ignition noise, I think someone had something running without  resistor 
>> wires
>> or plugs, strong and weak signals, no change.
>> I did have a bad street light out front of my house, the reason I  got 
>> the
>> NB, but they fixed it before I got the noise blanker.
>>
>> The main reason I asked was there seems to be no degradation of  signals 
>> with
>> the NB on at any setting.
>> On most rigs, you can hear a difference, and where its adjustable,  it 
>> makes
>> things sound really bad when you turn it up. The pro 3 is like that.
>>
>> On the K2, I have been unable to detect it doing anything at all,  any 
>> mode,
>> any noise, although the noise level I usually have is not bad.
>>
>> Thanks for the replies,
>> Brett
>> N2DTS
>>