This interesting circuit found in American documentation generates a busy signal, without you having to take the phone off the hook if you do not want to answer. The components used are common.
Found in an Electronic Design from the 90s, this circuit generates a mathematical function given by the...
This oscillator generates a fixed frequency signal determined by C1 and C2. In the case of 1 nF,...
This amplifier for distributing audio signals appears in other articles on this website and even...