optical switch circuit For detail in this circuit ,i will be to present thus as below. When the phototransistor (2N5777)is determined by the IR light, and leads to tension between the stroken 220k Ohm R resistance (any) for drive collector BC558 and the drop PHOTOTRANS from VCC to lower levels. IC4027 TTL signal output will be [...]
Simple Class A amplifier circuit This circuit is that of a simple class A audio amplifier. But with zero distortion, Q1 is a switch in the on or off, so that no load current by the resistance R2. In the best case, the tension in Q1 and the load resistance must be equal to the [...]
Here’s AC power supply circuit with low voltage output (step down transformer converter). Warning! This project involves the use of dangerous voltages. You must make sure all high-voltage (120 volt household power) conductors are safely insulated from accidental contact. No bare wires should be seen anywhere on the “primary” side of the transformer circuit. Be [...]
A milliamp meter can be used as a volt meter by adding a series resistance. The resistance needed is the full scale voltage reading divided by the full scale current of the meter movement. So, if you have a 1 milliamp meter and you want to read 0-10 volts you will need a total resistance [...]
Here’s a fire alarm circuit using LDR (Light Depending Resistor) as light sensor. It warns the user against fire accidents. It relies on the smoke that is produced in the event of a fire. When this smoke passes between a LED and an LDR, the amount of light falling on the LDR decreases. This causes [...]
