This circuit was found in an American documentation from the 90's. The transistor is a general purpose one. The circuit oscillates well between 12 and 30 MHz with the indicated components.
This circuit with a bargraph scale was found in a 90s Popular Electronics. The circuit measures...
This circuit with only one transistor was obtained in an old English documentation and can be...
This small transmitter that we found in a 1988 documentation, has a range that depends on the...