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.
We find this simple circuit that operates at a frequency of 5 to 10 MHz in an old English...
This is the traditional configuration of the 7806 as a 12 to 6 V automotive voltage reducer. The...
This is a single transistor stage for a phototransistor. The circuit is suggested by Texas...