When I was in the RAF many years ago, I bought a Nash Rambler Station Wagon that had a defunct radio. Being an electronics tech, I removed it and found the fault to be a burnt-out vibrator. I fixed it in about three minuets and had it running again. The vibrator is, as AndyY states, a method of obtaining ac current from a dc supply. The ac can then be transformed to higher voltages to power the radio valves. This is a Nash Rambler if you’re not familiar with it. LHD of course.
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