Society of Robots - Robot Forum

Electronics => Electronics => Topic started by: birdchee on August 29, 2008, 10:00:02 PM

Title: What these diodes do?
Post by: birdchee on August 29, 2008, 10:00:02 PM

(http://h1.ripway.com/cheechungheng/diode.JPG)

actually i don't understand what are the functions of this connection.
thanks.

Title: Re: What these diodes do?
Post by: RobD on August 29, 2008, 10:12:20 PM

If you were an electron (-) and wanted to go from the left side of the picture to the right side of the picture then you would only be able to go through the bottom diode.   

Title: Re: What these diodes do?
Post by: izua on August 29, 2008, 11:34:48 PM

That's used as a distorsion effect in guitar amps (the cheap ones). Using leds makes it sound a bit more soft.
I've also seen this kind of schematic in a homemade EKG, its purpose was to protect the samples to discharge through the human body.

Title: Re: What these diodes do?
Post by: birdchee on August 30, 2008, 09:39:48 AM

Hmm...I see I see.
Actually I saw this in the receiver circuit of ultrasonic ranger.
I'm not sure what are the exact funtions of it.

Title: Re: What these diodes do?
Post by: RobD on August 30, 2008, 10:07:12 AM

Ahh...  It could be a detector for the receiver.  When the sinewave returns, the detector can sense the high and low transitions to change the state of an input pin.

Title: Re: What these diodes do?
Post by: Admin on September 04, 2008, 07:04:10 PM

Sonar typically has really high voltages, like 300V or more . . . perhaps the diode is reducing the voltage of an AC signal?