This amplifier was found in a 1957 Rayrtheon documentation. The circuit can be fitted with a BC558 transistor. Driver and output transformers can be obtained from unused transistor radios.
The cut-off frequency of the filter shown in the figure can be adjusted to values between...
This circuit was found in a Popular Electronics from the 90s. The components used are all common...
This circuit uses a dual floodgate MOSFET not very easy to obtain today. Its handling is very...