Newsgroups: comp.robotics
Path: brunix!sgiblab!swrinde!gatech!howland.reston.ans.net!agate!library.ucla.edu!csulb.edu!csus.edu!netcom.com!nstn
From: nstn@netcom.com (Nathan Stratton)
Subject: Re: Problem with the Polaroid Board
Message-ID: <nstnCLJ43F.HLI@netcom.com>
Organization: Netcom Online Communications Services (408-241-9760 login: guest)
References: <2k1ntn$qd2@theben.kapsch.co.at>
Date: Sun, 20 Feb 1994 15:23:39 GMT
Lines: 35

In article <2k1ntn$qd2@theben.kapsch.co.at> martin.frischherz@kapsch.co.at (Martin Frischherz) writes:
>
>I just started playing with my Sonar Board. It seems to work. The time
>between the INIT signal and the returned ECHO signal was indeed proportional to 
>the distance of an obstacle.
>
>But I never got rid of the ECHO signal! Only a power down of the whole board
>made a reset. Neither a LOW on the INIT line nor a HIGH on the BLANK line
>was sufficient! What can I do? Cycling the power is boaring big time.
>
>Well, at first I have to repair the board. Touching the operating
>transducer, I got an electric stroke and the transformer began smoking. I
>found at least the transistor blown. I don't know about the transformer yet. 
>SIGH
>
>Back to the basic problem. How to get rid of the HIGH on the ECHO line?
>-martin
>
>-- 
>+ Martin Frischherz   :)-|-|-< -----------------------------------------------+
>| email: martin.frischherz@kapsch.co.at             | phone: ... hated ringing|
>| <<< KAPSCH-Telecommunications   Vienna - AUSTRIA  |   fax: ... wasted  paper|
>+------------------------  "I mean it must be HIGH or LOW" - John Lennon  ----+

Well don't feal to bad. I mounted 2 transducers on opsite sides of each 
other. I put foam on the back ot the transducers to keep the interference 
down. Well the foam was static foam and my transformer started smoking. 
As far as the echo line not going low, are you using a pull-up resistor? 


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 | Nathan Stratton  	                                                     | 
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