[Elecraft] P3SVGA - Coming soon

[Geoffrey Mackenzie-Kennedy]

Morning Fred,

When you see what appear to be the harmonics of WWV's audio tones, have you 
tried reducing the level of the signal reaching the K3 - P3 (e.g. by turning 
on the K3's ATT)?  If ATT is switched ON, does the amplitude of each tone 
harmonic seen decrease by the same amount (in db) as the tones themselves 
and the carrier ?

This test would help to narrow the search for the source of tones' 
harmonics, i.e. at WWV, or between WWV and your K3's attenuator, or 
somewhere after your K3's attenuator.

Up to the time when I had some useful antennas, July 2011, I cannot recall 
seeing any harmonic of WWV's tones when using WWV or WWVH to check the 
frequency calibration of my Perseus SDR, even when WWV's carrier level was a 
good S9 or higher.

Best wishes for Christmas, and a Happy New Year when it comes.

73,

Geoff
LX2AO


On December 19, 2011 1:30 AM, Fred Jensen wrote:


> Yes, one in particular ... WWV :-)  I still cannot explain what appear
> to be harmonics of the audio tones at levels I sure didn't expect.  I
> corresponded with someone at the station, he said they are sine waves
> derived from the cesium standards, asked for a photo, and thanks to the
> P3 Utility, I sent him two, one at about 5 KHz span, and one zeroed in
> on the carrier which clearly shows the 100 Hz sub-carrier and the IRIG-H
> time code modulation.  He assured me they were "on frequency" and I hope
> I explained that that was *not* the issue.  I have yet to hear back.  If
> anyone can explain what several of us see on the P3 when looking at WWV
> at narrow spans, I'd sure like to know.  I'm baffled.