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.
The frequency of this oscillator depends on the crystal used. The transistors are general purpose. We...
You can measure capacitances across a large range of values using the AC Power line frequency as...
The circuit of the figure serves the same purpose as the previous one (CB5057E), but has a...