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K2 off frequency

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yo2liw

K2 off frequency

Hello Om’s

I am the happy owner of a K2 and I need some advices on the alignment
procedure. My K2 is off frequency by about 300Hz. (I'm using an Orion for
the test)

I start from “4MHz Oscillator calibration” using an external counter. On TP3
the frequency on the internal counter is abt 12078 and 12.043 to 12044 on
the external one. I try to modify the value of C22 but no chance to make the
two equal. Until now I make all the measurements with the internal counter
and on the "PLL reference oscillator range test" the range was around 18 KHz
which I think is too much.

Any ideas?

Thank you!

Adi, Yo2liw

K2 Sn 4010

--
==============
Adrian Toplician
0721 367 850
Timisoara
YO2LIW
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Don Wilhelm-4

Re: K2 off frequency

Adi,

The PLL range has no relationship to the adjustment range of C22.
How confident are you that the external frequency counter is accurate?
That is an important consideration.

An alternate (and better) method is to tune the K2 to a station that you
know the broadcast frequency with precision. We here in the US can use
WWV, but there is a standard frequency station in Russia that works well
for those in Europe. I am not familiar with its tone transmit
structure, so you will have to gain some information about that station.

Take a look at the N6KR method for setting the reference oscillator
detailed on my website www.w3fpr.com article on K2 Dial Calibration -
substituting your standard station for WWV. That method does not depend
on anything other than tuning that standard station correctly (ignoring
the dial of the K2).
Once you have set C22 properly, continue with the steps in the procedure
and your K2 frequency readout should be correct to within 20 Hz.

73,
Don W3FPR

On 6/7/2011 6:17 AM, Adi Toplician wrote:

> Hello Om’s
>
>
>
> I am the happy owner of a K2 and I need some advices on the alignment
> procedure. My K2 is off frequency by about 300Hz. (I'm using an Orion for
> the test)
>
> I start from “4MHz Oscillator calibration” using an external counter. On TP3
> the frequency on the internal counter is abt 12078 and 12.043 to 12044 on
> the external one. I try to modify the value of C22 but no chance to make the
> two equal. Until now I make all the measurements with the internal counter
> and on the "PLL reference oscillator range test" the range was around 18 KHz
> which I think is too much.
>
>
>
>

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Dave, G4AON

Re: K2 off frequency

In reply to this post by yo2liw

Adi... further to the message by Don W3FPR, the Russian standard
frequency transmitter which is very strong in Europe is RWM. For their
frequencies and schedule see: http://www.irkutsk.com/radio/tis.htm

73 Dave, G4AON

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g3ymc

Re: K2 off frequency

But bear in mind this is at 9996kHz, 4 kHz away from 10MHz. I thought
the way the K2 PLL worked meant you had to calibrate at exactly 10MHz,
so calibrating against RWM may not give correct tracking on all
frequencies. It also transmits a pure carrier only for a few minutes
each hour, making it hard to use.

It is a pity that WWV is very rarely at a strong enough signal in
Europe to be used as a calibration reference and there is currently no
other one to use.

73 Dave G3YMC

On 7 Jun 2011 at 15:00, Dave, G4AON wrote:

> Adi... further to the message by Don W3FPR, the Russian standard
> frequency transmitter which is very strong in Europe is RWM. For their
> frequencies and schedule see: http://www.irkutsk.com/radio/tis.htm
>
> 73 Dave, G4AON
>

http://www.davesergeant.com

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Don Wilhelm-4

Re: K2 off frequency

Dave and all,

Actually the frequency of the station makes no difference at all. The
"secret" is that the difference between the VFO and BFO frequencies (in
LSB or USB only) is equal to the frequency of the station you are tuned to.
With 10 (or 15 MHz) WWV, the subtraction is easy since all but the first
digits of the station frequency are zeros, so all the lower order digits
will match. When using RWM or some other station that transmits on a
XXXX.00 frequency, that match will only occur in the digits after the
decimal - one should do the subtraction as a confirmation that there is
not a 1 kHz error.

73,
Don W3FPR

On 6/7/2011 11:41 AM, Dave Sergeant wrote:

> But bear in mind this is at 9996kHz, 4 kHz away from 10MHz. I thought
> the way the K2 PLL worked meant you had to calibrate at exactly 10MHz,
> so calibrating against RWM may not give correct tracking on all
> frequencies. It also transmits a pure carrier only for a few minutes
> each hour, making it hard to use.
>
> It is a pity that WWV is very rarely at a strong enough signal in
> Europe to be used as a calibration reference and there is currently no
> other one to use.
>
> 73 Dave G3YMC
>

yo2liw

Re: K2 off frequency

Hello Don

Thanks for the replay and all the useful info’s. It was quite easy to find
another counter (don’t know how calibrated) and now the difference is around
40Hz which is a great improvement from 300Hz.

Anyway I will try to use the RWM station signal also. Thank you everyone for
your time and advices. It is my first Elecraft, and I am really happy with
the rig.

Dave, Vincent, Dave thanks for additional info about RWM and calibration.

Best wishes!

73! Adi

Yo2liw

On Tue, Jun 7, 2011 at 7:05 PM, Don Wilhelm <[hidden email]> wrote:

> Dave and all,
>
> Actually the frequency of the station makes no difference at all. The
> "secret" is that the difference between the VFO and BFO frequencies (in
> LSB or USB only) is equal to the frequency of the station you are tuned to.
> With 10 (or 15 MHz) WWV, the subtraction is easy since all but the first
> digits of the station frequency are zeros, so all the lower order digits
> will match. When using RWM or some other station that transmits on a
> XXXX.00 frequency, that match will only occur in the digits after the
> decimal - one should do the subtraction as a confirmation that there is
> not a 1 kHz error.
>
> 73,
> Don W3FPR
>
> On 6/7/2011 11:41 AM, Dave Sergeant wrote:
> > But bear in mind this is at 9996kHz, 4 kHz away from 10MHz. I thought
> > the way the K2 PLL worked meant you had to calibrate at exactly 10MHz,
> > so calibrating against RWM may not give correct tracking on all
> > frequencies. It also transmits a pure carrier only for a few minutes
> > each hour, making it hard to use.
> >
> > It is a pity that WWV is very rarely at a strong enough signal in
> > Europe to be used as a calibration reference and there is currently no
> > other one to use.
> >
> > 73 Dave G3YMC
> >
> ______________________________________________________________
> Elecraft mailing list
> Home: http://mailman.qth.net/mailman/listinfo/elecraft
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>
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> Please help support this email list: http://www.qsl.net/donate.html
>

--
==============
Adrian Toplician
0721 367 850
Timisoara
YO2LIW
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