[Elecraft] K3 Noise Reduction

Wed Dec 15 13:52:54 EST 2021

I applaud the persistence it must have taken you to come up with that 
procedure, but it's actually kind of amusing to think about repeatedly 
doing all of that during a contest.

73,
Dave   AB7E

On 12/15/2021 9:52 AM, Bob McGraw wrote:
> The approach I use for the Noise Blanker is this.
>
> I first activate the NB and then the Level.   I start with the DSP OFF 
> and the IF OFF.  I then adjust the DSP value for optimum results 
> without it destroying the quality of the signal.  DO MAKE A NOTE OF 
> THIS VALUE.  Then set the DSP back to OFF.  Then move to the IF and 
> scroll through the settings in an effort to find optimum results.  
> Once this is done, leave the IF value as determined and return to the 
> DSP and set it to the value previously determined.
>
> This works for a given band and given type of noise.  Change bands or 
> noise and do it all again.  There is no ONE setting correct for every 
> condition.   Right now my 6M noise buzz is S-7 with the NB off.  Then 
> turning it ON and adjusted as above the 6M noise is S-3.  That's 4 S 
> units or 24 dB improvement.  I doubt you will get much better than this.
>
> As to Noise Reduction, I find it best performs for CW mode. Again it 
> takes careful adjustment to obtain optimum results.   I don't use NR 
> for SSB signals. I prefer to adjust the Attenuation value and the RF 
> Gain to produce optimum results when operating SSB.   I find optimum 
> results occur when the no signal band noise is about 10 dB above the 
> receiver noise floor.   In order to accomplish this operating point, 
> one will need to use ATTENUATION and RF Gain reduction.   More gain 
> won't aid in receiving weak signals, but just the opposite, as the 
> signal will pop out of the noise.
>
> I generally find using either NB or NR, but not both, is the better 
> way to operate.  I doubt there is anything wrong with your radio.  
> Most likely the result is more related to receiver setting parameters.
>
> 73
>
> Bob, K4TAX
>
>
> On 12/15/2021 9:46 AM, elecraft-request at mailman.qth.net wrote:
>> Message: 15
>> Date: Wed, 15 Dec 2021 09:36:26 -0500
>> From: Pete Smith N4ZR<pete.n4zr at gmail.com>
>> To: Elecraft List<elecraft at mailman.qth.net>
>> Subject: [Elecraft] K3 Noise Reduction
>> Message-ID:<dd5a2872-890f-feec-73ab-83a47b0d12ba at gmail.com>
>> Content-Type: text/plain; charset=UTF-8; format=flowed
>>
>> Last weekend during the 10 meter contest I was experiencing very loud
>> line-noise-like interference when my antenna was pointing south.? I
>> tried both my K3's Noise Reduction and Noise Blanker functions, and was
>> unable to find any setting that gave useful relief.? With the noise
>> blanker, in particular, I noticed that when it was on, not only was the
>> buzz still very strong, but it seemed as if all CW signals on the band
>> were being hum-modulated.? As soon as I turned off the noise blanker,
>> the CW signals cleaned up.? Is there something wrong with my radio, or
>> an adjustment issue, or is this interference simply too strong??
>> Obviously, I'll be trying to track it down, but it's not there all the
>> time, so that could be tough.
>>
>> -- 73, Pete N4ZR Check out the new Reverse Beacon Network web server 
>> at <http://beta.reversebeacon.net>. For spots, please use your 
>> favorite "retail" DX cluster. ------------------------------ Message: 
>> 16 Date: Wed, 15 Dec 2021 06:55:25 -0800 From: Dave <dave at nk7z.net> 
>> To: elecraft at mailman.qth.net Subject: Re: [Elecraft] K3 Noise 
>> Reduction Message-ID: <cfdb7170-cefb-9ef9-3b30-52c0bbac7b76 at nk7z.net> 
>> Content-Type: text/plain; charset=utf-8; format=flowed I have that 
>> same issue... I have some very dirty grow lights about two blocks 
>> from me. They are dirty as they come... Splattering across 80-20 
>> meters. The K3 has never been able to adequately clean up the crud 
>> from them. In defense of the NB/NR on the K3, the signals are on the 
>> order of S7 to S9, so my expectations may be too high for the K3. I 
>> just hope the K4 NB/NR work better in my environment. 73, and thanks, 
>> Dave (NK7Z) https://www.nk7z.net ARRL Volunteer Examiner ARRL 
>> Technical Specialist, RFI ARRL Asst. Director, NW Division, Technical 
>> Resources ------------------------------
>> Message: 17
>> Date: Wed, 15 Dec 2021 08:05:59 -0700
>> From: David Hachadorian<k6ll.dave at gmail.com>
>> To: Pete Smith N4ZR<pete.n4zr at gmail.com>,    Reflector Elecraft
>>     <elecraft at mailman.qth.net>
>> Subject: Re: [Elecraft] K3 Noise Reduction
>> Message-ID:<d8b87093-eab7-ebf8-168b-175fae9fc5a4 at gmail.com>
>> Content-Type: text/plain; charset=UTF-8; format=flowed
>>
>> For 12 years I've tried to get any enhancement of s/n from the K3 IF/RF
>> NB and NR.? I haven't seen one case where there is any improvement under
>> contest conditions.? When the s/n just starts to improve, the desired
>> signal is modulated and degraded by nearby signals to the point where
>> reception is better with NB/NR turned off.? As far as I can see, both of
>> these features are useless on the K3 under contest conditions.
>>
>> Dave Hachadorian, K6LL
>> Yuma, AZ
>>
>>
>>
>
> ______________________________________________________________
> Elecraft mailing list
> Home: http://mailman.qth.net/mailman/listinfo/elecraft
> Help: http://mailman.qth.net/mmfaq.htm
> Post: mailto:Elecraft at mailman.qth.net
>
> This list hosted by: http://www.qsl.net
> Please help support this email list: http://www.qsl.net/donate.html
> Message delivered to ab7echo at gmail.com 