In 1942, when this circuit was published, vibrators were still used in cars to convert 12 volts from the battery into high voltage for tube radios. The circuit makes use of 2 double tubes and 3 transformers to have a complete test of vibrators.

In 1942, when this circuit was published, vibrators were still used in cars to convert 12 volts from the battery into high voltage for tube radios. The circuit makes use of 2 double tubes and 3 transformers to have a complete test of vibrators.