Shortwave (SW) Transmitter with IC BEL1895

Here the SW transmitter circuit based on IC BEL1895. This particular transmitter circuit works in shortwave HF band (6 MHz to 15 MHz), and can be applied for shortrange communication and for educational purposes. The circuit is composed of a mic amplifier circuit, a variable frequency oscillator, and modulation amplifier stages. Transistor T1 (BF195) is… Read More »

25W Hi-Fi Audio Amplifier based LM1875

Here the circuit diagram of 25 watt Hi-Fi (high fidelity) audio amplifier that build based on single power amplifier IC LM1875 that should be run using heatsink attached on its. Components List: R1 _____________ 1K R2 _____________ 1M R3 _____________ 22K R4 _____________ 10K R5 _____________ 180K R6 _____________ 1R IC1 ____________ LM1875 C1 _____________… Read More »

200 Watt High Quality Audio Amplifier

This 200 Watt high quality power audio amplifier will give you top class quality for loudspeaker 4 – 8 ohm. Frequency range 20-20000Hz, Voltage 24-36V with current max 5A. You need heatsink to keep the transistor from overheating. Itu use dual polarity power supply to work, then you may use this power supply to supply… Read More »

20 Watt Audio Amplifier with LM1875

This is 20 watt audio amplifier circuit design which use IC LM1875 as main component. This circuit is simple and very easy to built. For stereo channel, you need to build the two same circuits which will amplify the both of audio channels (right and left channel). Dual polarity / symmetrical power supply required for… Read More »

Small Sound Amplifier for Ears (Hearing Aid)

This is the simple project of small sound amplifier for ears or often called hearing aid device or hearing loss amplifier. This circuit was already tested on some patients and give significant improvement in the hearing ability to the patients. It consumes a very small amount of power within the range of 10 milliwatts. Furthermore,… Read More »