P3 Continuosly Offset Waterfall Trace

Posted by K4SC on Sep 12, 2010; 6:24pm
URL: http://elecraft.85.s1.nabble.com/P3-Continuosly-Offset-Waterfall-Trace-tp5523982.html

The subject is terse, so here is what is happening.  I notice a very narrow but steady vertical line on my waterfall which does not move when I QSY.  This occurs only in CW mode and I can see it when the SPAN is narrow, ±5 kHz or less.  It appears to vary between bands but in the range of -600 to -800 Hz from the center frequency.  All other real signals track when I move the VFO, but this one just stays there, as if you drew a vertical line on the display.

As I am writing this description it occurred to me that it may be related to the CW sidetone, and sure enough, when I adjust the PITCH, the offset varies in relation to the center frequency of the P3 display.  In other words, when I raise the PITCH frequency the trace moves upwards; decreasing the delta between center and trace frequencies, and vice versa.   I put the radio in REVERSE CW mode to see if the trace would move to the positive side of the center frequency, but it just disappears.

I am a total novice to panadaptors or spectrum analyzers, so if this is a normal "thing", I am unaware.  It really does no harm, but I noticed it because I am using the waterfall a lot this weekend during the SKCC Weekend Sprint and I mistook it for a carrier that could never be heard.

I can not say whether it has been there all along or is a new quirk, as I just noticed it today.  I have removed and replaced all connections to the P3, ensuring their proper fit and tightness.

Any thoughts?