AquaDopp HR (2Mhz) - Burst Sample @ 8 Hz

Hello,

I cant seem to get a valid deployment configuration burst sampling at 8 Hz, with the extended velocity range box checked.

I receive an error message to (1) reduce the profile range, (2) increase the cell size, (3) increase the sampling rate, or (4) increase the measurement load.

By choosing 1,2, or 4 I cant seem to get a valid configuration.  The only way to alleviate this, it seems, is to not use the extended velocity range or decrease the burst sampling rate.

Is this an instrument limitation or a software bug?

 

Thanks,

Paul Stumpner

USGS Sacramento, CA

 

Hi Paul,

There are a bunch of checks on the configuration to try to ensure data return and prevent invalid configurations which would cause problems. Can you tell me what sampling configuration you're hoping to use (cell size, number of beams, etc.)? That will help trying to obtain a valid configuration.

P.J.

Thanks for getting back to me.

 

See attached screenshot. 

 

I'm not positive on the exact configuration check going not permitting this setup, but basically the problem is with trying to sample at both a fine spatial resolution (30 mm cells) and a high sample rate (8 Hz) and the number of pings that will physically occur in this time because of the speed of sound. Increasing the cell size to 50 mm results in a valid configuration, but because EVR uses about 1/3 of the normal water pings for ambiguity resolution, enabling EVR for the 50 mm cell size will result in too few samples for a valid velocity estimate.