This power step for relay activation was found in the 1964 RCA transistors manual. The circuit is of the NF type and the transistors admit equivalents. R4 depends on the drive voltage.
This amplifier uses common transistors and provides a power of 2 watts in a speaker of 4 to 8...
This medium wave transmitter uses two tubes and has a good range. L1 is formed by 30 + 70 turns of...
This powerful transmitter for the 27 MHz band was found in a Japanese publication from 1961. The...