Found in a Philips' 1968 documentation, this circuit is slightly different from the previous one. The components are also from the era, and modern equivalents can be used.
This amplifier uses a 1975 integrated circuit, which is uncommon today. The circuit has a gain of 30...
Using junction FETs, a configurable configuration is achieved for very low frequencies. FETs can...
This 2-terminal regulator was obtained from a 1990s National Semiconductor manual. The components admit...