K2 Guru needed KSB2 problem

[john lawrence-3]

Help please
 
I recently purchased a K2/100 with a number of options including the KSB2 SSB adapter. (serial number 4000 plus)
It was sold as a good working radio and it checks out ok at first glance. CW is working FB but the SSB is distorted with the MH-2 as it was set for this radio with the 5.6K resistor between pins 1 and 6 of mic jack. With the HC-5 Heil it sounds better but doesn't product the normal Christmas tree envelope on my scope. This is not an RFI related audio issue. It's the same sounding at low power (5, 10 or 100 w) or driving my KW amp

By reading through the KSB Operation Instructions it seems that I might need to tweak the BFO as a refinement. However I've found that SSBA and SSBC do not adjust with changes in settings. In fact, SSBA Level 1 mic gain is atten 10dB and no changes on the scope or sound in another receiver all the way up to Level 4. Compressor Ratios from 1:1 to 4:1 on SSBC show no changes to the envelop on the scope or sound on a second receiver. This test was conducted with both the MH-2 and HC-5 Heil but the Heil sounds much better. Both these mics work well on my K3
Maybe it's cockpit procedure. I may have missed some step in the menu configuration process. I need to get the basics functioning properly before venturing on into the BFO Optimization process that might clean up the muffled sounding audio on transmit.
Any helpful ideas from some of you who've lived with K2's will be greatly appreciated.

Thanks

73,
John, W1QS

e-mail: [hidden email]
______________________________________________________________
Elecraft mailing list
Home: http://mailman.qth.net/mailman/listinfo/elecraft
Help: http://mailman.qth.net/mmfaq.htm
Post: mailto:[hidden email]

This list hosted by: http://www.qsl.net
Please help support this email list: http://www.qsl.net/donate.html

[Don Wilhelm-4]

John,

I don't know how your SSB FL1 filter is set up, so I don't know what
audio range is covered by the passband.  Set it so the -3dB point on the
low frequency slope of the passband is positioned at 300 Hz and see if
that fixes things.

If you do not know how to do that, go to my website www.w3fpr.com and
look at the article on K2 Dial Calibration.  Part 3 of that article
deals with the filter alignment.  Do use Spectrogram or some other audio
spectrum analyzer.

If you are 'netting' at a specific frequency, it may be that your K2
dial calibration is off.  If that is a possibility, do all the steps in
the K2 Dial Calibration article.

73,
Don W3FPR

John Lawrence wrote:

> Help please
>  
> I recently purchased a K2/100 with a number of options including the KSB2 SSB adapter. (serial number 4000 plus)
> It was sold as a good working radio and it checks out ok at first glance. CW is working FB but the SSB is distorted with the MH-2 as it was set for this radio with the 5.6K resistor between pins 1 and 6 of mic jack. With the HC-5 Heil it sounds better but doesn't product the normal Christmas tree envelope on my scope. This is not an RFI related audio issue. It's the same sounding at low power (5, 10 or 100 w) or driving my KW amp
>
> By reading through the KSB Operation Instructions it seems that I might need to tweak the BFO as a refinement. However I've found that SSBA and SSBC do not adjust with changes in settings. In fact, SSBA Level 1 mic gain is atten 10dB and no changes on the scope or sound in another receiver all the way up to Level 4. Compressor Ratios from 1:1 to 4:1 on SSBC show no changes to the envelop on the scope or sound on a second receiver. This test was conducted with both the MH-2 and HC-5 Heil but the Heil sounds much better. Both these mics work well on my K3
> Maybe it's cockpit procedure. I may have missed some step in the menu configuration process. I need to get the basics functioning properly before venturing on into the BFO Optimization process that might clean up the muffled sounding audio on transmit.
> Any helpful ideas from some of you who've lived with K2's will be greatly appreciated.
>
> Thanks
>
> 73,
> John, W1QS
>
> e-mail: [hidden email]
> ______________________________________________________________
> Elecraft mailing list
> Home: http://mailman.qth.net/mailman/listinfo/elecraft
> Help: http://mailman.qth.net/mmfaq.htm
> Post: mailto:[hidden email]
>
> This list hosted by: http://www.qsl.net
> Please help support this email list: http://www.qsl.net/donate.html
> ------------------------------------------------------------------------
>
>
> No virus found in this incoming message.
> Checked by AVG - www.avg.com
> Version: 8.5.392 / Virus Database: 270.13.58/2304 - Release Date: 08/15/09 06:10:00
>
>  

______________________________________________________________
Elecraft mailing list
Home: http://mailman.qth.net/mailman/listinfo/elecraft
Help: http://mailman.qth.net/mmfaq.htm
Post: mailto:[hidden email]

This list hosted by: http://www.qsl.net
Please help support this email list: http://www.qsl.net/donate.html