From: aras@Ziggy.csl.ncsu.edu (Caglan M. Aras)
Subject: Polaroid Range finder interference-Help!
Organization: /etc/organization
Lines: 26

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.


-- 
Caglan M. Aras                 [] aras@eceris.ece.ncsu.edu
ECE Department                 [] ph: 919-515-5405
North Carolina State University[] fx: 919-515-5523
Raleigh, NC 27695              []
