TONE DISPLAY

Posted on Mar 10, 2013

The heart of the circuit is the tone (pitch) display section, based on the popular LM3914 display driver. This device drives ten LEDs in a linear display, with programmable endpoints and the choice of `dot` or `bar` modes of operation. Furthermore, it is possible to `chain` multiple devices for displays of virtually unlimited size.

Click here to download the full size of the above Circuit.

At this point we should note that the notes we are displaying represent a logarithmic scale, In other words, each time we double the frequency (go up an octave), the control voltage to our display section should increase by a fixed amount (about 1.5 volts

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