Found in an Electronic Design, this circuit makes use of general-purpose bipolar transistors. The circuit can be adapted to operate at lower voltages
With the name of transitube we find this MW receiver in documentation from the 50's. It uses a...
This circuit is from a 1998 Electronics Now and can be easily assembled since it uses a common...
This circuit is suggested by National Semiconductor and makes use of the negative regulator LM2990...