Based on the BA1404 integrated circuit, this circuit was found in the July 1992 issue of Radio Electronics magazine. The circuit is short range, but a power amplifier stage can be used.
This circuit, from a 1978 publication, uses a germanium power PNP, but the BD135 can be used for 6...
We have already explored this configuration in several articles on this site. This was found in an...
This thermometer, which uses common diodes as sensors, was found in a 1975 magazine -...