This is a condition associated with using the Hyde Park SUPERPROX proximity sensor in the Object mode (Figure 1).

When an object is properly positioned between the sensor and the window (See Figures 2 and 3), the ultrasonic pulse from the sensor will reflect repeatedly between the sensor and the object, thus creating a series of secondary echoes. A coincidental secondary echo condition exists when the distance traveled by the primary echo of an object at or within the window limits is a multiple of (most likely twice) the distance traveled by a secondary echo off the foreground object. As shown in Figure 3, Object #3 is properly positioned halfway between the sensor and the inner window limit and is mistakenly detected as if it were Object #1. Exercise caution when considering a SUPERPROX application to avoid this "false echo" condition.