We have a setup with with 13 polaroid transducers and rangefinders. We
would like to fire these three at a time with about 5 ms between
firings. The three that are being fired do not fire in the same
direction. 

To further explain the situation, assume we are firing sonars A,B,C
5 ms apart each other. We should normally see an echo on A that
corresponds to the distance. However, sonar A detects the INIT line
of sonar B! The detection is actually through the transducer of sonar A;
we can see a very faint 50Khz signal on the transducer, exactly at the
time the init line of sonar B is activated. 

We feel that there is some ground coupling that is causing this interference.
We came to this conclusion since we are using a separate power supply
for sonars B and C. 

Has anyone else had any problems with these particular units and
this type of experience? Your suggestions for remedies will be greatly
appreciated.

