Found in a1967 Ferranti documentation, this circuit uses an operational amplifier from that time. The circuit uses a LDR as a sensor and has a null setting.
This circuit assumes that a pulse produced by S1 has a constant duration determined by R1 and C1....
This circuit was obtained from an ancient American documentation. The coil consists of 80 to 100...
This circuit was found in Raytheon's 1967 documentation. The circuit uses an operating of the era,...