K2 "strange" Rx tuning effect

[Denis Jackson-2]

Hi!

This afternoon I got my new K2 to "Alignment and test, Part II"

All seems to be fine with one small exception - and maybe it's just just the
way it is but I thought I would ask anyway.

I applied a signal at -110dBm on 7.020Mhz to make the various tuning
adjustments.  Apat from not being able to peak L34 (which I see from earlier
posts is another story altogether) I noticed that tuning very slowlywith the
VFO results in what I can only describe as a little "chirrup" with every
10Hz step.  Is that just the way it is with this design or have I something
I need to look into?

73

Denis MW0CBC/GW8OQV

_______________________________________________
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-4]

Denis,

That little 'chirrup' should go away after you run CAL PLL.  Make
certain you have the bottom cover in place when you do run it.

L34 tuning is quite broad and should be adjusted for the best signal to
noise ratio.  Rather than using a signal generator, the best method is
to turn on the pre-amp and tune to the 7000 kHz birdie (no antenna
connected) and a banswidth of about 400 Hz.  If you have discerning
ears, you can hear the loudest signal and near the point you may hear
the minimum noise.  If you cannot hear it, set the slug somewhere
between 1 and 2 turns from the top.
When you get Spectrogram up and running for your final filter alignment
(that filter procedure is not in the manual but is on the Elecraft
website), you can use Spectrogram to observe the point where the signal
is still at maximum while the noise floor outside the passband is at a
minimum.

If you do not have it already, you can download Spectrogram 5.17 from
Tom Hammond's website www.n0ss.net.

73,
Don W3FPR

Denis Jackson wrote:

> Hi!
>
> This afternoon I got my new K2 to "Alignment and test, Part II"
>
> All seems to be fine with one small exception - and maybe it's just
> just the way it is but I thought I would ask anyway.
>
> I applied a signal at -110dBm on 7.020Mhz to make the various tuning
> adjustments.  Apat from not being able to peak L34 (which I see from
> earlier posts is another story altogether) I noticed that tuning very
> slowlywith the VFO results in what I can only describe as a little
> "chirrup" with every 10Hz step.  Is that just the way it is with this
> design or have I something I need to look into?
>
> 73
>
> Denis MW0CBC/GW8OQV
> _______________________________________________
> 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