This old fashioned transistor amplifier was found in a publication of the year 1958. Transformer are the critical components in the circuit and power comes from 6 D cells.
This filter was found in an 80's English publication. However, it can be implemented with modern...
This circuit, which can be used as a shield, was found in old documentation. The circuit must be...
Found in Philips documentation from 1968 this circuit operates at frequencies up to 10 MHz with 76...