This circuit is from the time when cars used contact breakers. This 80's version measures the dwell angle of the contact breaker for dwell adjustment using an era integrated circuit, the LM3917.
This oscillator uses a general-purpose transistor that can have BC548, BF494 or 2N2222 equivalents and...
Offset Adjustment on an Amplifier with the LM139 (CB14245E) In the figure we have the way of...
The critical components of this 1978 circuit are transformers, which, hopefully, can be obtained from...