[Elecraft] AGC INFORMATION

[brian]

Hi Matt,

I used to think I could copy CW signals below the noise.
However when I put SPECTROGRAM in line and actually measured the S/N 
ratio the results were disappointing.

According the SPECTROGRAM, those "in the noise" signals actually had an 
+8-10 dB S/N ratio.

Try it and see for yourself.

Likewise those WSPR and JT65 guys have been mislead by the -dB (e.g. 
-20) edited signal strengths.  They need to know that those are 
calculated with a 2.4 - 2.8 KHz assumed noise power.  In reality, many 
of the negative "dB" value signals can be copied by ear.

73 de Brian/K3KO

On 11/16/2016 2:37 AM, Matt Murphy wrote:
> Louis,
>
> FWIW I like my K3 noisy, almost so it sounds like there is no AGC action,
> just enough to protect my ears from an unexpected loud signal. I've found
> that this makes it easiest to copy extremely weak CW signals that are below
> the noise, and prevents static pops from covering up the signal.  The two
> settings to adjust are AGC threshold and AGC slope.  Start with threshold
> as it will make the biggest difference in how strong vs weak signals
> sound.  If you need finer-grained control, the AGC threshold can be useful.
> The other settings should be fine at their default values. The AGC decay
> "soft" setting is preferred by some in pileups, so you might try both
> settings.
>
> I found this writeup which looks pretty good:
>
> http://www.ad4c.us/Elecraft%20K3/AGC%20Tutorial.pdf
>
>
> 73,
> Matt NQ6N
>
> On Tue, Nov 15, 2016 at 7:42 PM, Don Wilhelm <donwilh at embarqmail.com> wrote:
>
>> Louis,
>>
>> I am not one to give you specific settings for you to just plug in and
>> use.  If I did so, I would just tell you to use the default settings.
>> Every location and operating style is different, and you can enhance the
>> AGC performance to meet your particular situation.
>>
>> Please read the "Noisy K3" information on my webiste www.w3fpr/com to give
>> you guidelines on how to adjust your particular AGC.
>> Pay particular attention to the method for evaluating the results of your
>> adjustments - it is critical that you listen to short gaps in the CW or SSB
>> voice to determine the best settings for you.
>>
>> 73,
>> Don W3FPR
>>
>> On 11/15/2016 5:46 PM, louis a. ives wrote:
>>
>>> I have been following the thread with regards to the setting of the AGC
>>> of the K-3 with great interest.  I am new to the use of the K-3 even though
>>> I have owned the radio for some time.  I had  a medical issue that delayed
>>> my use of the unit.    My K-3 has been updated with all of the current K-3s
>>> upgrades and I use a KPA500.  The thread has given several settings for AGC
>>> SLP and AGC THR but I noticed that the setting for the other AGC settings
>>> are not mentioned.  Should  I assume that the other default settings are to
>>> be used?   I tried the suggested settings and found that they did help with
>>> the reception of weak signals.  I work a lot of DX SSB and working the
>>> pileups can be a problem.  I also would like to thank KE7X for the great
>>> book on the K-3, it has been a great help and has answered a lot of
>>> questions.
>>> Any help would be appreciated.
>>> Thanks in advance
>>>
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