The Mini AV Test Box is a self countained VGA/3.5mm Audio output device for testing to see if speakers or monitors are working in a quick and easy way. The VGA signal output is simply 3 blocks of Red, Green and Blue. The audio output is a single tone that can be changed with a trimpot/knob.
Mini AV Test Box – [Link]
400W Stereo Audio Amplifier based on the original Marshall Leach involvement, but has made some improvements. Regarding the power supply voltage to the +-75V. VC comparing the performance of the modified Leach 700W/2R on one common board of both channels, as well as protection and control circuits for the fans. Compared to the 700W version a bit different in wiring. Because some things in the 700W version is completely tightened to perfection.
400W Stereo Marshall Leach Amplifier – [Link]
This audio amplifier project is a class AB audio power amplifier using a TDA2003 module power amplifier. It is easy to construct and has only a few external components. The module is designed with short circuit and thermal protection. It can drive loads as low as 1.6 ohm and is capable of delivering over 10 watts from a 16 V DC power supply. Figure 1 shows the TDA 2003 packaged and pin configuration.
Simple To Build 10 W Audio Amplifier! – [Link]
The LM49153 is a fully integrated audio subsystem designed for portable handheld applications such as cellular phones. Part of National’s PowerWise family of products, the LM49153 combines an earpiece switch, a high efficiency 25mW class G headphone amplifier, and a high efficiency 1.35W class D loudspeaker into a single device.
LM49153: fully integrated audio subsystem – [Link]
Many electronic projects require the use of a small audio amplifier. Be it a radio transceiver, a digital voice recorder, or an intercom, they all call for an audio amp that is small, cheap, and has enough power to provide adequate loudness to fill a room, without pretending to serve a disco! About one Watt RMS seems to be a convenient size, and this is also about the highest power that a simple amplifier fed from 12V can put into an 8 Ohm speaker.
LM386 Amplifiers – [Link]
This project is a Class-A Audio Amplifier based on 2SA1943 and 2SC5200 complimentary transistor pairs. This Super Class-A Amplifier is fully running at a bias of about 1.65A @ 35V, which it resulting in about 58W of continuous dissipation per transistor in the output stage. In this condition, you can highly imagine that the heat sink runs in a hotter temperature, where it can reach approximately 40 Celsius degrees!
Super Class-A Amplifier – [Link]
DS1802 is a Stereo Digital Volume Control IC. It consists of two 65-position, 45kΩ digital potentiometers with logarithmic resistance properties incrementing 1dB per step. It can be operated under automatic software control via a serial 3-wire interface where wiper settings are written with 8-bit words, or under push button control with simple contact closure.
DS1802 Stereo Digital Volume Control – [Link]
This project is an easy audio amplifier based on 8 pin DIP LM386 integrated circuit.
The potentiometer is the volume control. The heatsink is screwed to an LM7812 12V voltage regulator. There are a couple of caps and a diode on there. The wire with what looks like gum on the end of it is actually the headphones jack wire with a three-pin header molded onto the end using that really cool putty “as seen on TV” that you knead together and it forms really hard parts. I used it to protect the super-thin wires of the headphones jack. The little chip on that board is the LM386. The red- and black-tipped wires coming into the top of the breadboard just left of the diode and the voltage regulator are the leads from a Radio Shack 12V, 500 mA wall wart.
LM386 Easy Amp – [Link]