Using the 2N2646 this circuit was found in a Radio Electronics magazine from July 1968. The transistors are from the time and the lamp can be replaced by a high-power LED in a current version.
TQP92xx series power amplifiers for frequencies in the typical range of 1,805 -2,200 MHz can be...
This is one of the possible timer configurations with the 555. We found it in October 1986 Radio...
This power supply for those who want to feed and recover 5 ¼ floppy disks was found in the...