This is the circuit for the HM-10ª, an instrument sold by Heathkit. The circuit is from a Radio Electronics from May 1963. The indication is by an analog instrument.
This circuit was obtained from Radio Electronics from the 90s. The infrared sensor is of an...
This circuit is suggested by Motorola and is based on a 1723 voltage regulator. The 2N3055...
Found in documentation from the 1980s, this circuit generates signals that can reach a few...