This is the circuit diagram of portable mic preamp. This circuit consumes low current supply (about 2mA), so will have a long battery life for supplying the circuit. Harmonic distortion is about 0.1% @ 1V RMS output for all frequencies. Maximum input voltage (level control cursor set at maximum) = 25mV RMS. Maximum input voltage… Read More »
This a simple stereo electret microphone pre amplifier circuit. The below design diagram is the design for single channel, but the design of PCB layout is for stereo design og electret mic pre amp. For maximum performance, better quality, use solid capacitors or film capacitors and metal film resistors (1% tolerance). schematic diagram:
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 the circuit diagram of mic condenser amplifier. The low-cost and compact mic condenser audio amplifier described right here is deliver good-quality audio of 0.5 watts at 4.5 volts. It could possibly be applied as a part of low-power transmitters, packet radio receivers, intercoms and walkie-talkies.
Here’s the circuit diagram of a 70W stereo power amplifier which built using single power IC STA550. The circuit is simple and require little additional electronic components to support the work of IC STA550. This power stereo amplifier works with dual polarity / symmetrical power supply. Since based to the datasheet, the negative supply range… 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 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 »
LM4809 Datasheet Document. Boomer audio power amplifiers were designed specifically to into 32 0.1% (typ) provide high quality output power with a minimal amount of external components. Since the LM4809 does not require bootstrap capacitors or snubber networks, it is optimally suited for low-power portable systems.
This is the FM transmitter circuit which apply 4 radio frequency stages, that are a VHF oscillator designed around transistor BF494 (T1), a preamplifier designed around transistor BF200 (T2), a driver designed around transistor 2N2219 (T3) and also a power amplifier designed around transistor 2N3866 (T4). A condenser microphone is wired at the input of… Read More »