This circuit was found in a Signetics documentation from the 1980s. The integrated is a PLL and the SCR is a general purpose type The pitch frequency is given by R1 and C1 as formula next to the diagram.
This multi-function filter can be used as a shield controlled by TTL signals. At the high level it...
This 100 kHz crystal oscillator uses 7404 to generate square signals. We found it in a Popular...
This circuit supplies 5 V from two AA batteries. The output current is 4 mA, resulting in an 11 mA...