Found in a Popular Electronics this circuit has double regulation. The integrated circuits used provide a maximum current of 1 A and must be provided with heat sinks.
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...