K2 SSB problem

[GS-3]

Hi group!

I have a little problem with SSB it seems. During the contest last weekend
someone told me I had "frequency modulation" on my signal. Not knowing what
this should mean I at least thought I would check the signal when bands are
quieter. I just did. And although the audio sounds ok there is maybe a
little problem. Sending a 1kHz audio signal the receiving station could hear
the same signal at +1kHz and -1kHz with -20dB max. These signals should be
at least -40dB, correct?

Question. How do I fix this?

Thanks!



Gerhard Schwanz
DH3FAW
mailto:[hidden email]
http://www.gs-personal.de


_______________________________________________
Elecraft mailing list
Post to: [hidden email]
You must be a subscriber to post to the list.
Subscriber Info (Addr. Change, sub, unsub etc.):
 http://mailman.qth.net/mailman/listinfo/elecraft   

Help: http://mailman.qth.net/subscribers.htm
Elecraft web page: http://www.elecraft.com

[Don Wilhelm-3]

Gerhard,

There could be a problem, or there may be no problem at all.  What is the
audio source and  level that you are driving into the mic jack?  If it is
not a pure sine wave or the level is too high, it will have harmonics or (if
too high a level) can cause harmonics if the balanced modulator is being
overdriven.  Sorry, but there is just not enough information in your note to
allow me to venture even a guess.

In any case, harmonics of the modulating audio are not any indication of
frequency modulation - frequency modulation would cause a variation in the
frequency of the carrier plus/minus the modulating frequency.

73,
Don W3FPR

> -----Original Message-----
> From: [hidden email]
> [mailto:[hidden email]]On Behalf Of Gerhard Schwanz
> Sent: Friday, April 01, 2005 4:25 AM
> To: [hidden email]
> Subject: [Elecraft] K2 SSB problem
>
>
> Hi group!
>
> I have a little problem with SSB it seems. During the contest last weekend
> someone told me I had "frequency modulation" on my signal. Not
> knowing what
> this should mean I at least thought I would check the signal when
> bands are
> quieter. I just did. And although the audio sounds ok there is maybe a
> little problem. Sending a 1kHz audio signal the receiving station
> could hear
> the same signal at +1kHz and -1kHz with -20dB max. These signals should be
> at least -40dB, correct?
>
> Question. How do I fix this?
>
> Thanks!
>
>
>
> Gerhard Schwanz
> DH3FAW
> mailto:[hidden email]
> http://www.gs-personal.de
>
>
> _______________________________________________
> Elecraft mailing list
> Post to: [hidden email]
> You must be a subscriber to post to the list.
> Subscriber Info (Addr. Change, sub, unsub etc.):
>  http://mailman.qth.net/mailman/listinfo/elecraft
>
> Help: http://mailman.qth.net/subscribers.htm
> Elecraft web page: http://www.elecraft.com
>

_______________________________________________
Elecraft mailing list
Post to: [hidden email]
You must be a subscriber to post to the list.
Subscriber Info (Addr. Change, sub, unsub etc.):
 http://mailman.qth.net/mailman/listinfo/elecraft   

Help: http://mailman.qth.net/subscribers.htm
Elecraft web page: http://www.elecraft.com

[Trevor Day]

Hi Gerhard,
Most reports of "FM'ing" I have been aware of have been due to a low
power supply voltage and/or the voltage varying with the load.  I have
not heard a K2 with this problem, but it might be worth checking the
power supply.

gl
Trev G3ZYY

In message <001f01c5369c$9d5c5800$fc7ca8c0@oemcomputer>, Gerhard Schwanz
<[hidden email]> writes

>Hi group!
>
>I have a little problem with SSB it seems. During the contest last weekend
>someone told me I had "frequency modulation" on my signal. Not knowing what
>this should mean I at least thought I would check the signal when bands are
>quieter. I just did. And although the audio sounds ok there is maybe a
>little problem. Sending a 1kHz audio signal the receiving station could hear
>the same signal at +1kHz and -1kHz with -20dB max. These signals should be
>at least -40dB, correct?
>
>Question. How do I fix this?
>
>Thanks!
>
>
>
>Gerhard Schwanz
>DH3FAW
>mailto:[hidden email]
>http://www.gs-personal.de
>
>
>_______________________________________________
>Elecraft mailing list
>Post to: [hidden email]
>You must be a subscriber to post to the list.
>Subscriber Info (Addr. Change, sub, unsub etc.):
> http://mailman.qth.net/mailman/listinfo/elecraft
>
>Help: http://mailman.qth.net/subscribers.htm
>Elecraft web page: http://www.elecraft.com
>

--
Trevor Day
UKSMG #217
www.uksmg.org

_______________________________________________
Elecraft mailing list
Post to: [hidden email]
You must be a subscriber to post to the list.
Subscriber Info (Addr. Change, sub, unsub etc.):
 http://mailman.qth.net/mailman/listinfo/elecraft   

Help: http://mailman.qth.net/subscribers.htm
Elecraft web page: http://www.elecraft.com