We found this preamplifier for the 10 and 11-meter range in an old documentation for radio amateurs. The integrated circuit used is uncommon today.
Found in a 90s Popular Electronics, this circuit provides a current of 3 to 5 A depending on the...
We found this circuit in the 1964 RCA transistors manual. The sensor may be a common LDR and the...
This circuit has tone control, and its power depends on the supply voltage. The circuit is from...