[Elecraft] P3 - Displaying my signal

[Alan Bloom]

The P3 is supposed to freeze when the K3 is transmitting.  However, when
the K3 is set for CW semi break in, it unfreezes after the first
character.  This is a bug not a feature.  :=)

If you would like to view your transmitted signal for test purposes, you
can do it by temporarily disconnecting the RS-232 cable to the K3.  That
disables the freeze-on-transmit function.  What you are viewing is stray
IF leakage coming out the K3's IF OUT connector.  The signal level is
rather low and varies with drive level, frequency band, and the
particular K3.

However, I do find it useful for adjusting the transmit equalizer.  With
my K3 set for SSB, I turned on peak hold on the P3 and talked into the
mic for a few seconds.  The peak value is a fair representation of the
transmitted spectrum.  I could see that it was way too bassy (low audio
frequencies stronger than the highs) which results in a muddy-sounding
signal that lacks "punch".  It took maybe 5 minutes playing around with
the K3 TX equalizer to get a nice flat spectrum.

Alan N1AL


On Wed, 2010-10-13 at 13:22 -0400, Gary Ferdinand wrote:
> A new feature seems to have appeared with my K3/P3 combo, both factory
> assembled.  Whenever I key the K3 on an empty daytime 80 meter band, I get a
> narrow, but strong waveform down about 300-400 Hz from the marked carrier
> frequency.   If I hold key down for a few seconds the spike builds to about
> -80dBm from a noise base of about -130dBm.    I searched the archives but
> all I saw was something about a phantom signal.  This is not phantom at all.
> Of course it also shows brilliantly in the waterfall display.
> 
> I have checked that all cables and power connected to both units are well
> attached.  Also, this feature appears to be new, have been created overnight
> by Murphy.  All suggestions welcome.  Thanks.
> 
> Gary W2CS
> 
> 
> 
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