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K3: Use AM SYNC on WWV to calibrate DDS?

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K1LI

K3: Use AM SYNC on WWV to calibrate DDS?

AM-S in FW 3.97 works great. I notice that my frequency displays 15.000.024 when tuning in WWV on 15MHz and 10.000.16 on the 10MHz signal. (Happily, the displayed frequency is the same on both "sidebands.") The ratio of the 15MHz/10MHz received frequencies is equal to the ratio of the 24Hz/16Hz difference between the displayed readings and the "actual" signal frequencies (I trust WWV!).

Is there a lesson here that I can use to improve the frequency calibration of my K3?

73 -- Brian -- K1LI

Don Wilhelm-4

Re: K3: Use AM SYNC on WWV to calibrate DDS?

Brian,

I would suggest you re-do the Reference Oscillator calibration - page 50
in the manual, use Method 2.

73,
Don W3FPR

K1LI wrote:

> AM-S in FW 3.97 works great. I notice that my frequency displays 15.000.024
> when tuning in WWV on 15MHz and 10.000.16 on the 10MHz signal. (Happily, the
> displayed frequency is the same on both "sidebands.") The ratio of the
> 15MHz/10MHz received frequencies is equal to the ratio of the 24Hz/16Hz
> difference between the displayed readings and the "actual" signal
> frequencies (I trust WWV!).
>
> Is there a lesson here that I can use to improve the frequency calibration
> of my K3?
>
>
>

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Dunc Carter - W5DC

Re: K3: Use AM SYNC on WWV to calibrate DDS?

The method that I use to calibrate the frequency of my K3 is to use 2.5,
5, 10, and 15 MHz WWV as calibration signals and adjust CONFIG | REF CAL
on cw so that the signals are as close to 600 Hz as possible as measured
in multipsk's spectrum display in psk31, highlighting the WWV frequency
and reading the audio frequency of the spectrum line in multipsk's RX
frequency text display. Because of the way the K3 generates its
signals, the calibration varies from band to band but I can easily keep
the K3 within +/- 1 HZ using this method. I have settings for each of
these WWV frequencies in memory on adjacent memory settings so I can
check them momentarily once I've clicked M>V once quickly without
needing to click M>V a second time.

I'm a paid multipsk customer but it's a free download at the level
needed to do this.

Dunc, W5DC
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Mike Harris

Re: K3: Use AM SYNC on WWV to calibrate DDS?

In reply to this post by Don Wilhelm-4

G'day,

And remember that this isn't a once and for all time operation.
Components age and reference oscillators have long term drift.
Method 2 is easy to do.

Regards,

Mike VP8NO

----- Original Message -----
From: "Don Wilhelm" <[hidden email]>
To: "K1LI" <[hidden email]>
Cc: <[hidden email]>
Sent: Wednesday, May 19, 2010 10:04 AM
Subject: Re: [Elecraft] K3: Use AM SYNC on WWV to calibrate DDS?

> Brian,
>
> I would suggest you re-do the Reference Oscillator calibration -
> page 50
> in the manual, use Method 2.
>
> 73,
> Don W3FPR
>
> K1LI wrote:
>> AM-S in FW 3.97 works great. I notice that my frequency displays
>> 15.000.024
>> when tuning in WWV on 15MHz and 10.000.16 on the 10MHz signal.
>> (Happily, the
>> displayed frequency is the same on both "sidebands.") The ratio
>> of the
>> 15MHz/10MHz received frequencies is equal to the ratio of the
>> 24Hz/16Hz
>> difference between the displayed readings and the "actual" signal
>> frequencies (I trust WWV!).
>>
>> Is there a lesson here that I can use to improve the frequency
>> calibration
>> of my K3?

Nr4c

Re: K3: Use AM SYNC on WWV to calibrate DDS?

In reply to this post by K1LI

K1LI <[hidden email]> wrote:

>
>AM-S in FW 3.97 works great. I notice that my frequency displays 15.000.024
>when tuning in WWV on 15MHz and 10.000.16 on the 10MHz signal. (Happily, the
>displayed frequency is the same on both "sidebands.") The ratio of the
>15MHz/10MHz received frequencies is equal to the ratio of the 24Hz/16Hz
>difference between the displayed readings and the "actual" signal
>frequencies (I trust WWV!).
>
>Is there a lesson here that I can use to improve the frequency calibration
>of my K3?
>
>73 -- Brian -- K1LI
>--
>View this message in context: http://elecraft.365791.n2.nabble.com/K3-Use-AM-SYNC-on-WWV-to-calibrate-DDS-tp5074859p5074859.html
>Sent from the Elecraft mailing list archive at Nabble.com.
>______________________________________________________________
>Elecraft mailing list
>Home: http://mailman.qth.net/mailman/listinfo/elecraft
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>Post: mailto:[hidden email]
>
>This list hosted by: http://www.qsl.net
>Please help support this email list: http://www.qsl.net/donate.html
>

The Smiths

Re: K3: Use AM SYNC on WWV to calibrate DDS?

If you really want to get your K3 right on target with the Ref. Cal setting, you can use a free program called Spectrogram and set up marker tones at your pitch freq. and 100Hz above your pitch freq. Set your rig on WWV and match the peaks of the tones to the markers... Once you have those centered perfectly on the markers you'll be within .05Hz. Doesn't get too much better than that.
Be sure to let your rig warm up for about an hour before you make the adjustments.

> Date: Wed, 19 May 2010 14:45:25 -0400
> From: [hidden email]
> To: [hidden email]; [hidden email]
> Subject: Re: [Elecraft] K3: Use AM SYNC on WWV to calibrate DDS?
>
>
>
> K1LI <[hidden email]> wrote:
>
> >
> >AM-S in FW 3.97 works great. I notice that my frequency displays 15.000.024
> >when tuning in WWV on 15MHz and 10.000.16 on the 10MHz signal. (Happily, the
> >displayed frequency is the same on both "sidebands.") The ratio of the
> >15MHz/10MHz received frequencies is equal to the ratio of the 24Hz/16Hz
> >difference between the displayed readings and the "actual" signal
> >frequencies (I trust WWV!).
> >
> >Is there a lesson here that I can use to improve the frequency calibration
> >of my K3?
> >
> >73 -- Brian -- K1LI
> >--
> >View this message in context: http://elecraft.365791.n2.nabble.com/K3-Use-AM-SYNC-on-WWV-to-calibrate-DDS-tp5074859p5074859.html
> >Sent from the Elecraft mailing list archive at Nabble.com.
> >______________________________________________________________
> >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
> >
> ______________________________________________________________
> Elecraft mailing list
> Home: http://mailman.qth.net/mailman/listinfo/elecraft
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> Post: mailto:[hidden email]
>
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