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This binary to decimal converter matrix was found in a 1964 General Electric publication. It can be used on modern equivalent circuits, including as a shield.
This is an old test circuit for integrated TTL counters, feeding a Nixie tube, common at the time....
This old oscillator using germanium transistors has a high impedance headphone as inductor to...
This preamp with several inputs using germanium transistors from the time was found in Japanese...