Igor, Bill, Mike --
UA3DJY wrote:
>> Hello Mike,
>>
>> Width of the tones is the reason behind it: each single tone
>> occupying spectrum of the several tones, it is Doppler effect.
>>
>> I wrote message on it to Joe K1JT some time ago, this propagation
>> issue had not high priority in the WSJT-X project.
No, this problem has nothing to do with a Doppler effect.
There is no way that a propagation effect would cause glitches
simultaneously on several different signals.
G4WJS wrote:
> It may be as simple as a dry joint or broken screen connection
> somewhere in the audio chain.
Not likely, I think.
The horizontal streaks I called attention to are almost certainly the
result of jumps in the digitized signal's phase when its amplitude was
nonzero. Dropouts -- brief loss of signal but no loss of relative
timing in the stream of digitized samples -- would not cause such streaks.
To test a system for audio glitches, tune the radio so as to put a
reasonably strong steady carrier at, say 1000 Hz in the WSJT-X
waterfall. You could use an RF generator, but equally good is an AM
signal -- say WWV, or a signal in the broadcast band. Set Bins/Pixel =
1 and N Avg = 1 and watch the resulting spectrum. If using an AM
station, ignore any sidebands caused by its modulation.
What you're looking for is horizontal streaks like the ones in the
screen shot I posted. With a strong, clean test signal, these will be
*very* easy to see if the audio system is producing glitches. (Of
course, any well behaving system will NOT show glitches.)
-- 73, Joe, K1JT
Signal dropouts
------------------------------------------------------------------------------
Site24x7 APM Insight: Get Deep Visibility into Application Performance
APM + Mobile APM + RUM: Monitor 3 App instances at just $35/Month
Monitor end-to-end web transactions and take corrective actions now
Troubleshoot faster and improve end-user experience. Signup Now!
http://pubads.g.doubleclick.net/gampad/clk?id=267308311&iu=/4140
_______________________________________________
wsjt-devel mailing list
wsjt-devel@lists.sourceforge.net
https://lists.sourceforge.net/lists/listinfo/wsjt-devel
