This mic preamp uses the low noise IC uA739. The circuit is an example of how a good preamplifier can be designed for dynamic microphones. The IC houses two identical integrated preamp circuits. The ...

This audio amplifier circuit is useful in classrooms to reduce the strain of lecturing ,if the surrounding environment is noisy. It uses the power amplifier IC LM380 that gives 2 watts output which is ...

Circuit boards etched and drilled. This is a closeup of one side of the microphone PCB board. As you can see it is a little crowded. The copper pipe before work began. Success! The mic head’s windows ...

IT is not absolutely necessary that the microphone should form part of the direct circuit. It works just as well if connected so that, when the carbons are not touching, the whole of the current goes ...