This an old commercial receiver found in a year 1958 magazine. The circuit uses some transformer available that timer and the transistors are germanium types. The circuit is intended to receive MW stations.
The author has many books he had written in Eglish (See the Biography) published by famous...
This oscillator can run in frequencies up 10 MHz depending on the Power supply voltage. The 1 µF...
Found in an American paper from the 90's, this circuit can be adjusted to pass frequencies above 30 to 300...