[Elecraft] K2 Problem in NAQP

[Don Wilhelm]

Jim,

This is a very good example where the user should understand his radio - 
especially what is displayed for the frequency for each mode.  For the 
K2 in either SSB or RTTY mode, it will be the suppressed carrier 
frequency - in CW it will be the carrier frequency of the signal 
(provided that you are hearing at the same pitch that you have set for 
your sidetone pitch).

With the K3, what is displayed depends on the data sub-mode.  DATA-A 
will be like SSB where the suppressed carrier frequency is displayed - 
AFSK-A and FSK-D submodes will display the mark frequency (as long as 
you have set the proper mark frequency in the K3 menu).  CW is subject 
to the same considerations as for the K2.

I cannot speak for how other transceivers calculate the frequency 
displayed on the dial - it will be transceiver dependent, so the user 
should consult the matching manual for that information.  One clue is to 
observe whether the receiver changes the frequency display when changing 
modes.  The K2 and K3 do not change the displayed frequency when 
changing between CW and SSB - which should tell you that the K2 and K3 
are displaying the carrier frequency (suppressed or not).  Those that 
change the displayed frequency are most likely displaying the frequency 
the transceiver is tuned to (including the CW offset).

For example, my Yaesu FT-900 indicates the correct frequency when tuned 
to a CW signal at the same pitch I have set for the sidetone, but if I 
switch to SSB mode (on the same sideband as I am using for CW), the 
frequency changes by 600 Hz and I still hear the same audio tone.  With 
the K2 and K3, the displayed frequency does not change, but listening to 
a CW signal in CW mode, I will not hear the signal when switching to SSB 
because it goes to zero audio frequency.

I know it is confusing, but I hope that I have made the point that each 
receiver may do it differently.  Valid conclusions cannot be drawn until 
you know how each transceiver handles the displayed frequency.  
Introducing RTTY and data modes further complicate the picture.

73,
Don W3FPR



On 7/20/2011 12:24 PM, radioshoppe wrote:
> Rich and other interested parties,
>
> As I understand what you are saying is that the frequency displayed on K3 is
> actually the mark frequency rather than the suppressed carrier frequency.
> > From my observations of the K2, as compared to the K3 in on air test, it is
> the same.  I have compared my transmitted and received frequency with an
> FT-950 and FT-5000 and those radio's are essentially the mark frequency
> below the K2.  In other words, If they are transmitting on 21.080.00 I have
> to tune the K2&  K3 to 21.082.150 to hear them and for them to hear me.
>
> I don't see a problem in actual use other than if you agree to meet someone
> on a certain frequency you have to add the mark frequency to the displayed
> frequency to be communicate with them.
>
>