This low-cost, general-purpose electronic hearing aid works off 3V DC (2x1.5V battery).
In this circuit, transistor T1 and associated components form the audio signal preamplifier...
Here is a simple non-contact AC power monitor for home appliances and laboratory equipment that should remain continuously switched-on. A fusefailure or power breakdown...
From understanding basic circuits to creating complex circuits, from analog to digital circuits, from designing circuits on PCs to circuits analysis, these free ebooks...