I am getting strong spikes at about 48 second spacing for the last week or
so.  I suspect my power supply but have not confirmed yet.  It began shortly
after moving the instrument and adjusting the zero output level.  I have
posted pictures at http://mit.midco.net/rpratt/   The top graphic is a
WinQuake view at 12 sps.  On the bottom is a Windaq trace at 240 sps showing
the spike as a short oscillation followed by a smaller wave.  If I look at a
series of spikes I see they fall into 2 types with one going up first and
the second down first but they do not always alternate in that pattern.  FFT
of the 240 sps trace also shows some 60 hz coming through.   Does anyone
have any thoughts?

 

Randy

 














I am getting strong spikes at about 48 second spacing =
for
the last week or so.  I suspect my power supply but have not =
confirmed
yet.  It began shortly after moving the instrument and adjusting =
the zero
output level.  I have posted pictures at =
http://mit.midco.net/rpratt/ 
 The top graphic is a WinQuake view at 12 sps.  On the bottom =
is a
Windaq trace at 240 sps showing the spike as a short oscillation =
followed by a
smaller wave.  If I look at a series of spikes I see they fall into =
2
types with one going up first and the second down first but they do not =
always
alternate in that pattern.  FFT of the 240 sps trace also shows =
some 60 hz
coming through.   Does anyone have any =
thoughts?

 

Randy