We found in an old magazine of our collection, from the year 1958, this interesting circuit of an insulation test that can apply up to 1500 V in a test whose indicator is a simple neon lamp.
The tubes used are the popular 1B3 valves used at the time as high voltage rectifiers in televisions. Two of them form a rectifier that generates up to 1500 V for insulation tests selected by a wrench.
The critical component in addition to the tubes is the transformer. A current version of this circuit can be made using high voltage rectifier diodes that can be achieved on out of use televisions. A self-transformer can be used to generate high voltage.
Also note that the capacitors used must have a working voltage of at least 600 V. Use polyester types for this purpose. The current of the transformer is very low, on the order of 20 mA.
See in our article Sources For Tubes Devices how to build an alternative source for this circuit.
We remind you that the tests with this unit are exclusively for circuits and devices that support the generated voltages. In figure 1 the complete diagram of the apparatus.
