Burst mode "Jumps"

Hi,

There seem to be initial jumps in the ancillary data (pressure, voltage, temperature; see attached figs) whenever the AquaDopp HR wakes-up and starts to a new burst. Things apparently "settle down" after a couple or so measurements into each new burst. Not clear if that happens also in the velocity signals and/or other signals. 

Best,

Ayal

Dear Ayal, we have been working on this problem.  The technical background is a long story (actually several years long...) but it has to do with the fact that the sensor sampling and the velocity sampling is asynchronous.  As a result, bad things can happen if you try to sample a sensor when the acoustic transmitter is operating.  The problem is gradually getting better in the newer firmware versions but for now I would recommend simply disregarding the first sensor data in a burst. 

The velocity is not affected by this issue.

Best regards, Atle Lohrmann

OK - thanks. So, is this a general problem no matter the sampling strategy (and, if so, is the first spike averaged together with  the good data for the case of regular sampling), or is this only for burst modes? 

Ayal

Yes, it is a general problem. The sensor data are stored every 1 s so it only affects this very first sample - once every burst or just the very first sample in case of continous sampling.