[Elecraft] PSK31 -- ghost image:

[Rich Lentz]

I will agree that when you overdrive the transmitter you will produce =
ghosts
and all kind of other spurious signals. But, if the person(s) =
transmitting
causes all the "ghost(s)" that I observe how does that explain my
observations.

I receive ghosts that have the EXACT same frequency DIFFERENCE of =
signals
that are within the pass band of the K2, Icom 706, etc., HOWEVER, the =
ghosts
are more than 2 kHz outside of the pass band of the receiver.   Right =
now I
am observing a pair of ghosts at 4.6 kHz and 4.9 kHz caused by two =
signals
at 1.1 kHz and 1.4 kHz. (Do you realize how strong of a signal would be
required to receive a signal at 4.9 kHz (audio) on the K2?). The MixW =
IMD
reading on the signals causing the ghosts is -23 and -31, which leads me =
to
conclude neither of them are overdriving their rig.  Further, when I =
observe
these ghosts (when caused by only two signals in the pass band), when =
either
one of the transmissions stops, BOTH of the ghosts disappear. =20

The same phenomena happens with three or more ghosts, with the exception
that when the strongest transmission stops all of the ghosts disappear, =
when
either one of the weaker transmissions stop the position now depends =
upon
the new sum of audio frequencies. With my cheap sound card I can observe
this with the volume of the K2 set at 8:00 or less (the main signals are
barely visible and the audio from the PC speaker is also barely =
audible).  =20

=20
Rich
KE0X