🚀 go-pugleaf

In article <1icacgINNn10@uwm.edu>, albrecht@csd4.csd.uwm.edu wrote:
> 	1)  Where can I purchase a relatively cheap and accurate ultrasonic
> 	    transmitter/reciever set? (Phone #, Addresses)

I don't know about a set but National Semi used to make an ultrasonic
ranging chip set: Xmtr & Rcvr in same package LM 1812 I believe. Was
outlined in their  Linear databook a few years back. 

 > 	2)  Can I get a Receiver(1) to receive more than one frequency at
 >	    once?  Say for example:
 >						)--TRANS #1
 >						)--TRANS #2
 >			RECV --(		        )--TRANS #3
 >							)--TRANS #4
 >							)--TRANS #5
 >							)--TRANS #6 

 >	   Where each transmitter (1-6) is on it own frequency?
Freq was dependent on resonant freq of transducer, 40 Khz for atmospheric
type, 200 Khz for hydrophone type (used for 'spinning neon bulb' type fish
detector). 

 >	3)  If I cannot receive these signals simutaneously, then can I
 >	    receive them in a sequence of say .25 second as such:

I believe there was a trigger or gating circuit of some type.

Jeff.