US Transducer Information


New Member
Hi all,

Thought I'd make another thread as this is a slight side-question on the other one.

In short, I'm using the ultrasonic transducers shown below:

Do these have polarity? If so, which is which?

I've tried searching for a spec sheet, but I can't seem to find this info.


Michael 2727

Senior Member
They are a piezo device, and respond much like a speaker.
The only real reason for polarity on a speaker is to correctly
phase the devices, e.g. out of phase speakers will cancel
each other out, mainly noticed in the Bass by mere mortals.

With the U/S transducer the case is -0V or NEG.
Also the TX will work as an RX and vice versa.
(there may be slight mechanical differences where
one works better than the other)


Senior Member
My money would be on the ST being the transmitter and the SR being the receiver :)

The two bottom pins both look to be soldered to the cases so I'd expect them to be 0V.