PIC CARILLON

THIS design produces bell-like sounds, using the multiple harmonics of sinewaves to give the tonality expected from bells, complete with the decay of each note played. In its simple standalone form, as described here initially, it is triggered by a 4 × 4 matrix data keypad. This allows the 12 notes of an octave,
including sharps, to be generated. The remaining four keys causes the octave of the note to be changed, providing a complete four-octave range.

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Serial IO controller & analogue sampler

Looking for an easy-to-drive I/O controller? This unit connects to the serial port of your PC and can be programmed to switch relays, in response to voltage, resistance, temperature and digital inputs. It also includes comprehensive system timers to control the relays and you can set the system up to operate as a PLC-style controller.

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Low-Voltage Adjustable Regulator

Need to operate a CD, DVD or MP3 player from the cigarette lighter socket in your car? Or perhaps run a digital still or video camera or some powered speakers from the power supply inside your PC? This Low-Voltage Adjustable Regulator will step the voltage down to what’s needed. It has jumper shunts to select one of six common output voltages (from 3V to 15V) and depending on the input voltage and the heatsink(s) you use, it can deliver an output current of just over 4A.

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ACCURATE ELECTRONIC STOP-WATCH

Here is a simple circuit which can be used as an accurate stop-watch to count up to 100 seconds with a resolution of 0.01 second or up to 1000 seconds with a resolution of 0.1 second. This stop-watch can be used for sports and similar other activities.

 

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Running Message Display

Light emitting diodes are advantageous due to their smaller size, low current consumption and catchy colours they emit. Here is a running message display circuit wherein the letters formed by LED arrangement light up progressively. Once all the letters of the message have been lit up, the circuit gets reset.

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