Tag Archives: led display

Hacks and Mods: Tweeter Used to Sense Vibrations

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The creator built a neat looking project which uses a piezoelectric element from a tweeter to detect vibrations. He is using a Zilog eZ8 series microcontroller which seemed to be very popular years ago. This project dependently using a strong vibration while the enclosure has been placed on the top… Read more »

Temperature Range Indicator Using a Window Comparator

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A window comparator usually employs 2 comparators with one output indicating the input is somewhere between two limits. In these examples, a third comparator is added to display all three conditions where the input is in the center range, or higher, or lower.The first example uses a thermistor to indicate… Read more »

+/– Voltage On Bargraph Display

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The LM3914 is a truly versatile component. Besides LEDs, only a few other components are needed to make the ‘bidirectional’ bargraph voltmeter shown here. The circuit is similar to a conventional bar display, but it offers a possibility to change the direction in which the LEDs are switched on. This… Read more »

20 Output Sequencing Circuit by IC digital

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I to see this circuit in web http://home.cogeco.ca/~rpaisley4/Traffic145.html good idea circuit. Basic Circuit Operation The circuit is stepped through the sequence by an adjustable LM555 astable oscillator. The Oscillators output is divided by a 74LS90 divider into a 10 step BCD weighted output. The BCD output then drives two 74LS145… Read more »