Differential Temperature Controller.

This circuit measures the temperature difference between 2 sensors and activates a relay when they are different

This ON-OFF Switch circuit using a 555 timer is simple, useful and easy to implement.

This circuit has many applications on places where it is necessary to activate and deactivate (connect and disconnect) an electrical or electronic device.

20 Amp Variable Power Supply using LM317

This 20 Amp Variable Power Supply varies its output voltage from 1.5 to 15 volts and is based on the well-known variable voltage source configuration, where only the LM317 voltage regulator is used.

This Relaxation oscillator using an UJT transistor circuit serves to generate signals for power control devices such as thyristors, TRIACs

LM317 variable voltage regulator circuit diagram.

LM317 characteristics. How the voltage regulator circuit works, Regulator circuit operation improvement

Fire alarm circuit using thermostats and SCR.

This circuit uses several thermostats in parallel for its operation. They can be as many as you want and must be placed in the places where you want to sense the temperature.

Zener diode Voltage regulator calcutation

A Zener diode Voltage regulator calcutation is made using a simple circuit of a resistor /Rs) and a Zener diode (Z).

This two elements values and characteristics are obtained using special formulas

Logic probe circuit with CD4001 IC

This logic probe circuit is useful for people who needs an instrument to measure the logic levels on digital circuits. This circuit is implemented with CMOS IC technology and is recommended for testing circuits using the same technology

Temperature alarm circuit with 741 operational amplifier

This temperature alarm circuit with operational amplifier activates a relay when the temperature of the place to be controlled exceeds a set level. Useful for an oven temperature control or a cooling system

Car Battery Monitor Circuit

This Car battery monitor circuit is very simple and very interesting. How many times have you found that the car does not start because the battery is discharged?

555 IC Tester Circuit (PCB)

This 555 IC tester circuit, allows us to make sure that this integrated circuit works properly. This same test can be achieved by operating the 555 as astable multivibrator, but this test does not allow
to observe its operation in detail.

Car Battery Booster Circuit

This Car Battery Booster Circuit, is very useful when the car battery has low charge or does not deliver the expected current to operate the starter motor.