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.
In the figure we have an application for NLAS5113, a new device from on Semiconductor...
This circuit, which draws numbers from 00 to 99, was found in an Italian magazine from 1974, but...
The filter shown in the figure, suggested by Motorola, operates at a cut-off frequency of 1 kHz,...