View single post by Slider2732
 Posted: Apr 4th, 2009 11:36 AM
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Joined: Mar 3rd, 2008
Location: Muskogee, Oklahoma USA
Posts: 349
Following on from reading karlos1212's post:

All of this really got me thinking about devices again. I've had a short interlude, while becoming fascinated by radio controlled aircraft, but now following that hobby method of posting a build log for aircraft, would like to start a build log for an Ultrasonic Generator.
My basis for the circuit is a bit of a cheat, it's a 4 oscillator micro-synth I built a couple of years ago. The wiring is a little horrendous lol, but it does work and may well be a good platform from which to build up the rest of the system.
The synthesizer itself was called 'Big Blue' and due to the method of enabling echo effects by using a big blue capacitor in a semi feedback fashion. Well, the circuit itself further appeals for this project because of the use of LED's to relay to me visually what each oscillator is doing. The 4 generators output square waves.
Reading Karlos's first link on his post at: you can see that using 3 square wave oscillators, mixed, LED's for output ---- it's kinda looking like the right place to start :)

From this initial circuit, which, by the way was built to use up some damaged chips and give them a use which then exploded into a full project, I intend to forward the LED stage to multiple infra-red LED's, which then broadcast the signals. Reception of the signals via infra red recievers obtained from PC mice and furthered by the probable use of TV remote control circuits (I kid you not) will then be converted to sound through a speaker.
Later, I wish to construct the scanning section of the original circuit.

Here's an original pic, unfortunately dark and blurred, of Big Blue. I'll be taking more.


4 square wave oscillators on the left, frequency output LED's to their right. Mixing stage section further right and amplified output at the top. The circuit features a little one octave keyboard at the bottom, which of course won't be used. One other thing perhaps of mention is that the circuit enables outside sound to be mixed too with the oscillator outputs. All WAS music based but now aims to be of paranormal use :D