Strange signal seen on P3

[Bill Swindell - K1LED]

I noticed on my P3 a single spike displayed on the right side of the screen. The signal is 12.45mhz from the center frequency. As I tune the radio, the P3 display shifts so that the radio frequency remains in the center of the P3 and the extra signal stays on the right side of the P3 display. What causes this erroneous display?

[Tom Azlin N4ZPT-2]

Change your span, does it go away? Change it further, does another spike
show up?  Turn off the K3, does it go away?

My answers were yes, yes, and no. I did find some spans with no spikes.
  Lucky the ones I use. I still need to go back and search for them
again now that I have reconfigured my shack layout.

I presume some sort of internal P3 spur with the SVGA card in place.

73, tom n4zpt

On 4/3/2012 10:38 PM, Bill Swindell - K1LED wrote:
> I noticed on my P3 a single spike displayed on the right side of the screen.
> The signal is 12.45mhz from the center frequency. As I tune the radio, the
> P3 display shifts so that the radio frequency remains in the center of the
> P3 and the extra signal stays on the right side of the P3 display. What
> causes this erroneous display?

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[Tony Estep]

On Tue, Apr 3, 2012 at 9:38 PM, Bill Swindell - K1LED <[hidden email]
> wrote:

> I noticed on my P3 a single spike displayed on the right side of the
> screen.
>
===========
Bill, sounds like this is a spike that comes from I-Q imbalance. With most
SDR programs, if you tune in a strong carrier to the left of the center
line, built-in automatic I-Q balancing will attenuate and soon eliminate
this spike, and it won't come back. I don't have a P3 right now, but as I
recall the P3 did work that way as well.

Tony KT0NY
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[Tobyp]

Hi Bill,   I don't see any strange spike on my P3.  running 1.13 version.  In fact,  I am not experiencing many of the things I see posted to the forum.

But I am only using a SONY 15 inch LCD monitor and it just looks great!

Toby  W4CAK