Tiny visual zero beat indicator

This circuit is suitable for an indicator to audio signal lower than 3Vp-p. In the circuit, we use a very small parts with only two of the LED display and built-up resistor for current depression. Light-emitting diodes(LED) connected with reverse polarity provide a visual indication of zero-beat frequency. Each Led… Read more »

The stray magnetic fields meter.

Electronic technology is common. Although it has much useful. But it is a kind of environmental pollution. Which is called “Electomog” or we will called Stray Magnetic fields (SMFs). And, Some experts said that “SMFs” has effect to the human body. The SMFs that is referenced in this project will… Read more »

Electronic Thermometer with versatile control.

Technology does not stand still. This electronic thermometer that display by LED 20 level and The peripheral Bells Alarms. When the temperature reaches the preset value. On a daily basis. We have to work a lot. If someone would have noticed and remind us always. To the dangers of heat… Read more »

The cheap digital voltmeter using CA3162 and CA3161

This digital voltmeter circuit is a saving, easy to use Because it is smaller than a typical circuit, I believe that, after I presented this circuit. You will certainly like it. This circuit can be used as Versatile. Features of the circuit : – 3-digit numeric display with LED 7… Read more »