The DS1669 is an electronic digital rheostat manufactured by Dallas Semiconductor. This component has a function similar to digital variable resistor/potensiometer which can be operated by push the buttons. You can adjust the audio volume, LCD contrast, frequency, etc. by using two buttons instead of a common potentiometer/trimpot. This circuit explains how we do it… Read More »
This is a basic circuit of car horn and lamp flasher that starts playing the vehicle horn at whatever point your vehicle is backward rigging. The circuit (First Diagram) utilizes double clock NE556 to create the sound. One of the clocks is wired as an astable multivibrator to produce the tone and the other is… Read More »
This is the circuit diagram of drinking water alarm based a small water sensor by using aluminium foil and plastic foil, and connected to a very simple alarm based a 555 IC timer. The Jal State Board supplies water for a limited duration in a day. The time for water supply is determined by administration… Read More »
This is the 300W RMS stereo power amplifier circuit project. This amplifier is based four pieces of power IC TDA7294. It’s mean that every single channel of the circuit uses two ICs in bridge mode. In this application, the load value must not be less than 8 Ohms.
This is an active stereo tone control circuit using very well known op-amp IC of TL072. The circuit include mic pre-amp and mixer control. In this design, we have two inputs: one for line (stereo), one for microphone and has control of the three audio frequency (high/treble, medium and low/bass). It also provide balance control… Read More »
This is a very interesting circuit design to assemble. There are 4in1 amplifier module in a circuit board. 100W power amplifier using the TDA7294, for the VU meter uses IC LM3914. The tone control preamp uses the well-known IC 4558. The symmetrical power supply module also included in the PCB.
This is 120W power amplifier schematic using TO-3 package complementary transistors, NPN and PNP polarity. The well-known power transistor pair of 2N3055 and MJ2955 used in this circuit. +/- 50V symmetrical (split/dual polarity) power supply with minimum 3A electric current should be used for maximum performance.
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 »
This is the schematic diagram of 400W RMS stereo power amplifier which use power transistor to work. This amplifier in addition to providing good sound power, also with excellent quality and a high fidelity with low noise, to obtain the 400 watts we can put 2 speakers of 4 Ohms or 4 of 8 Ohms.… Read More »