Ultrasonic transducer pins

[farnoise]

Hi All,
I have a ultrasonic transducer (fish-finder) that I bought off e-bay. (Just the transducer not the LCD ). it has no manufacturer name nor model number so i can't pull the data-sheet up. I am trying to find the GRND-VCC, and the Signal-Out Pin on the connector end.

it's an older version and only has 3 pins so that made my job easier but i dont know how to find which is which? I don't want to just randomly tap the pins and burn the sensor.
I now it's a 15 V though.

Cheers

 

[tpetar]

Yes one of them is serial bus. Usually what I saw Gnd is in the middle, and power positive can be red, and yellow is serial I/O. But this means nothing.

Did you check resistance between pins using ohmmeter?

Can you provide sharpen photo?

 

[farnoise]

I guess you mixed it up with robotic sensor. Here is a picture of it
http://i.ebayimg.com/00/s/NzY4WDEwMjQ=/$(KGrHqV,!p8E8WnzEVzNBPSSpIVbVg~~60_1.JPG?set_id=8800005007

Here is a similiar item on ebay. I had a hard time taking picture and posting it, sorry for that
**broken link removed**

 

[tpetar]

I'm definitely thinking of something else. :smile:

Its for fishing.

 

[farnoise]

Lol yeah I figured. I am using this for underwater porpuses on my ROV since I need a lower frequEncy. But its practically the same I just don't want to take the shield off and color-code it. Do you think I can use oscolliscope to see the output and feed it 15 V?

 

[FvM]

I don't know how the three pins are conncted, but it's most likely just the transducer without any electronics. You'll drive it with a 200 kHz (or whatever the resonance frequency is) burst.

You can start with a resistance + capacitance measurement to get some insights.