R1 may be 10k and R2 100k. The transistor can be the BC548 and instead of the small lamp we can use a series LED with a 1k resistor. D1 is germanium and C1 is 10 nF. C2 can be 47 nF.
This circuit was published in a 1979 magazine, but it can still be easily assembled as the...
This circuit was found in a documentation of the 80's having characteristics of high overvoltage given by...
Here we show how a Constant Current Source can be created in the Multisim Blue using a common BJT...