This is an amplifier circuit intended for modulating transmitters. The 5-tube circuit is from an American manual from 1947. The power supply uses a transformer.
The frequency of this oscillator depends on the amount of light incident on the LDR. The circuit,...
This circuit divides the frequency of a signal by two. The circuit is found in the May 1977 issue...
We found this circuit in the Texas Instruments opto-electronics manual. The button resets and the...