This circuit was suggested by National Semiconductor in one of its manuals. The LM108 integrated circuit, uncommon nowadays, can be replaced by an equivalent. The power supply must be symmetrical.
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...