This circuit was found in a 1967 Delco Radio documentation. The circuit has an input voltage of 250 V and the load current is 2 A. The transistors used are from that time.
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...