68
58-603 Pulsar
®
Model R86 Radar Transmitter
APPENDIX
Custom Echo Rejection
INTRODUCTION
The Pulsar Model R86 has a unique feature that allows for a user to manually adjust a Standard Echo
Rejection curve. Custom Echo Rejection is a feature intended to allow a user to manually adjust the
curve to account for undesirable waveform features (noise, disturbances, etc.) that may not have been
captured by the initial Standard Echo Rejection curve.
For example, undesirable signals may occur if the original echo rejection curve was taken at a time
when mixing blades were stopped in a particular location If the blades then stop in a different loca-
tion a false echo from the blade could then appear in the live echo curve. Custom Echo Rejection
allows the user to manually modify the Standard Echo Rejection curve in order to ensure that all
“false echoes” are cancelled out of the waveform.
The Custom Echo Rejection curve is offered in addition to the Standard Echo Rejection curve. Once
a Custom Echo Rejection curve has been created, either curve is available for use by the user to reject
unwanted echo echoes. The user has the ability to select which curve (or no curve) will be used for
echo rejection.
Since the local display does not have the ability to concurrently display the live and rejection echo
curves, the manipulation of the echo rejection curve will be done in the DD and DTM only. The abil-
ity to view the two curves graphed together is essential in determining how the rejection curve should
be modified to provide the desired outcome.
The Echo Curve graph will show only one of the two echo rejection curves at a time, with the Custom
Echo curve always shown as Curve 2.
When the Custom Echo Rejection curve is selected for use, the “New Rejection Curve” button will
change to “Modify Rejection Curve”. Clicking on this button will guide a user through modifying an
existing echo in the custom curve, copying an echo from the live curve to the custom rejection curve,
or resetting a Custom Echo Rejection curve back to the original form from which it was taken
(Standard Echo Rejection curve).
OPERATION
BEFORE STARTING: Note that changes to certain parameters cause the Echo Rejection profile to
become invalid. Those parameter changes will invalidate both the Standard and the Custom rejection
curves simultaneously, regardless of which echo rejection curve option is selected at the time. For
example, making any changes to Gain parameters (Dielectric, Turbulence, Foam and Sensitivity) or
Tank Height parameter will invalidate all Echo Rejection Curves whether Standard or Custom.
