5W Tube Amplifier with EL84

Here is the circuit diagram of the classic 5W Tube Amplifier with EL84 as the final amplification component. This is a single channel amplifier (mono) of course with single input and single output. You should build the two similar circuit to make it stereo.

Dark and Light Activated Relay

This is the basic dark and light sensor which using photoresistor as sensing component. The transistor act like as a switch, when the “switch” in on condition then the relay will be activated.

25W HiFi Audio Amplifier with MOSFET

This is high fidelity, high quality 25W HiFi audio amplifier circuit delivers great audio performance. You don’t need pre amplifier circuit for this design since it can be directly connected to the input devices such as computers, phones, radios, TVs, etc. Component list: R1,R4 = 47K 1/4W Resistors R2 = 4K7 1/4W Resistors R3 =… Read More »

Simple Fire Alarm with Thermistor and NE555

The following circuit is a simple fire alarm circuit based NE555 timer and use thermistor as a temperature detector. This sensor will activate the transistor when the temperature is in high value. The thermistor will have a low resistance at high temperature, while at low temperature, the transistor resistance is high. This characteristic of thermitor… Read More »

“Hum” Remover

Here is the hum remover circuit diagram. “Hum” usually occured from live audio system, for example: input from microphone. Hum can be removed from an audio signal to get the maximum performance by mixing the actual hum with an antiphase hum in equal level. You can use any NPN transistor to support this circuit.

6V Gel Cell Battery Charger

The following scheme diagram is the battery charger circuit for 6V Gel Cell battery type only. Components List: R1 = 22 ohm, 1W R2 = 270 ohm R3 = 220 ohm *R4 = 715 ohm, 1% *R5 = 3.57K, 1% *R6 = 1.40K, 1% *R7 = 1.47K, 1% C1 = 0.1uF, ceramic C2 = 0.1uF,… Read More »

22W Stereo Power Amplifier with TDA1554

Here the circuit diagram of 22W stereo power amplifier. Powered with main power IC TDA1554Q, this circuit works up to 22W for each channel. For stereo channel, the power output should be up to 2 x 22W . A few externel components required to support the main component. Heatsink on the power IC is a… Read More »

Mini MW Transmitter

The following is a circuit of a simple AM transmitter. This circuit is available in kit form and can work well since the kit available on market. This circuit uses a combination of transistors SA101 and SA103, as the modulation signal amplifier.


Page 10 of 58« First...89101112...203040...Last »