frequency meter circuit

Measures the temperature using the DS18B20 temperature sensor, displays the reading on a 2x16 character LCD, sends the data to a serial terminal, and checks the temperature against predefined limits. The output is set high if the temperature is...

A DSB transmitter is significantly less expensive to construct compared to an SSB transmitter since it does not require filters or phasing networks. This circuit can generate an output of up to 1 watt on the 10-meter band. The...

The timing circuit utilizes the 556 dual time base circuit, which includes an intermediate access N8281 crossover network. This design does not require a large volume capacitor, allowing for extended time delays. Initially, the first half of the 556...

This circuit can be used to operate an electric strike or an electromagnetic lock on a door. It is not the door being opened/closed, but a small electromagnetic strike which unlocks the door. The opener has the following features...

This circuit is highly dangerous due to its output voltage, which is in kilovolts and poses a significant risk of serious injury or death. It should only be attempted by individuals with extensive experience in handling high voltages. No...

This free-running TTL square-wave oscillator features a variable frequency output spanning a 20:1 range or better. It utilizes four of the six inverters in an SN7404 chip along with additional components. The frequency of oscillation is dictated by the...