Found in a 90s R-E Experimenters Handbook, this circuit amplifies signals from 100 Hz to 3 MHz. The circuit has a gain of approximately 30 dB. Bipolar transistors are general-purpose types.
The critical point in this 2005 project is the adjustment of the optical system, mainly to avoid...
In this circuit of a 1968 publication the unijunction may be 2N2646 and the transistor BC548. The...
We find this circuit in documentation from the 1980s. The triac and diac are of conventional types...