[Elecraft] Auto-Notch Broken in 3.25 (I probably missed this)

[Brett Howard]

Made me go look again as well.

with 50uV injected into the back I got an AFV of 1773.  I first centered
the signal in CW and then changed to SSB.  I have the auto offset
feature turned on so my rig was still centered and I know the frequency
of the tone this way.  This allows me to use my pitch frequency for the
manual notch setting and I know I'm centered (or as centered as the CWT
gets me as I did not use my ear this time to zero beat). 

Auto notch = -35.9dB
Manual notch = -46.2dB 

Then I repeated the experiment with 1uV injected:

Auto notch = -7.8dB
Manual notch = -11.2dB

Its clear to the ear that the auto notch is not doing as good of a job
in comparison to manual but I'd not say that its "not working".  

Doing this test made me think of an idea though.  What about when
engaging the manual notch if you were in auto before how about having
the manual set to the same frequency that the auto algorithm found
rather than 2k.  This would then hopefully mean you'd only have minor
tweaking to get it perfect.  Although hopefully the auto improves a lil
in the future too...

All in all the auto notch is still doing a quite fair job in my shack!

~Brett (KC7OTG)

On Sun, 2009-08-16 at 15:25 -0700, Ron D'Eau Claire wrote:
> Ya' made me go look (again) Mike:
> 
> On mine, both auto and manual work, but the manual notch is much deeper than
> the automatic notch. 
> 
> Using the K2's internal metering while invoking the notch listening to a
> clean input from a signal generator, I see a 38 dB drop in level using the
> automatic notch and a 51 db drop using manual notch. 
> 
> Ron AC7AC
> 
> 
> -----Original Message-----
> G'day,
> 
> To hopefully settle this, at least for my own case, I reloaded Beta 
> 3r19 and did the following test:
> 
> 14195kHz SSB, AGC F.  S7 signal from my K2.  With my line out 
> setting this gave a -46dB signal displayed in Spectrogram 16. 
> Applying auto notch reduced this to -87dB or better.
> 
> Reloaded Beta 3r25.  With the same set up the signals displayed 
> were -46dB notch off, -72dB notch on.
> 
> I conclude that something significant has changed with auto notch.
> 
> Regards,
> 
> Mike VP8NO
> 
> 
> ______________________________________________________________
> 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