Found in a 90s 303 Circuits, this circuit uses the KTY10 sensor, widely used at the time.
This circuit with an industrial standard 4-20 mA interface uses a KPZ20G pressure sensor but can...
This simple receiver with germanium transistor and listening on a crystal phone was discovered in a...
This circuit is from Motorola technical documentation from the 70s, but it can be easily assembled...