This small commercial radio for the MW band with germanium transistors was found in Japanese documentation from the 1960s. The circuit is powered by a 9 V battery and has a 455 kHz IF.
This circuit monitors extra-low frequency (ELF) fields. We found it in an American documentation from the...
We can use any type of resistive transducer with central resistance in the range of 10 k ohms to 1...
This circuit controls two lamps so that when one increases in brightness the other decreases. The...