Bakelite was patented on December 7, 1909. The creation of a synthetic plastic was revolutionary for its electrical non-conductivity and heat-resistant properties in electrical insulators, radio and telephone casings and such diverse products as kitchenware, jewelry, pipe stems, children’s toys, and firearms.
SR-400 Production years were 1965-69
400 W PEP, 360 W CW (power input), 20-tube 80-10 Meter CW/SSB Transceiver “Cyclone”. Dual conversion receiver. Include VOX, PTT, AALC, Product detector, 1650 KHz crystal lattic filter, CW side-tone, crystal calibrator, combined R.F output & S-meter, noise blanker, RIT with a 3 KHz offset, driver tube is a 7558. External power supply.