K2 80M No BFO

[Curt]

Rarely operate 80M, but today wanted to listen to the NAQCC net on 3575.  Amazingly, there was no BFO.  I could hear the CW as rushing carrier noises, but no tones.  CW on the other bands receives just fine.  LSB receives fine on 75M.  Everything was fine on 80M about a month ago.

Thoughts?

73, Curt KB5JO
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[Don Wilhelm-4]

  Curt,

I have to disagree with your assessment.  The BFO must be active even to
hear a "rushing noise" - this is a fact with product detectors.

What I am also saying is that there is nothing band dependent about the
filter center to BFO alignment - it will be the same for all bands.

The fact that you can hear LSB signals on 75 meters also says there is
nothing wrong with the BFO using the SSB filters -  but that is not the
same filter as used for CW reception - I suspect filter alignment
problems with the filter widths you are using for CW.

I would do other checks as well.  What is the R30 voltage across the 3.5
to 4.0 MHz range?  Is it within the 1.5 to 6.0 volt range?
Have you aligned your IF filters using Spectrogram?  Or have you simply
set them to the frequencies indicated in the manual?

I suggest you re-do your IF filter/BFO alignment first following the
steps in the K2 Dial Calibration article on my website www.w3fpr.com.  
Once the filters are aligned correctly, then check all bands, the BFO
note should be the same for all bands.

73,
Don W3FPR

On 11/7/2010 9:19 PM, Curt wrote:

> Rarely operate 80M, but today wanted to listen to the NAQCC net on 3575.  Amazingly, there was no BFO.  I could hear the CW as rushing carrier noises, but no tones.  CW on the other bands receives just fine.  LSB receives fine on 75M.  Everything was fine on 80M about a month ago.
>
> Thoughts?
>
> 73, Curt KB5JO
> ______________________________________________________________
> 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
>

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