This commercial receiver from the year 1958 uses two AA cells as Power supply. The circuit is intend to receive MW station and the transistors are germanium types not easy to find today.
This 1967 Electronics World circuit is suitable for frequencies up to 1 MHz. The setting applies...
This circuit was obtained from Maxim documentation. The circuit has 4.5 and 5.5V thresholds for...
This amplifier circuit for instrumentation was found in the manual of the used integrated circuit...