This RF preamplifier for the 450 MHz band was found in an amateur radio documentation from the 1980s. The transistor supports an equivalent operating at the recommended frequency.
This telegraph monitor was found in an American documentation for radio amateurs from the 1970s. The...
We found this circuit in a European publication from the 1970s. The transistor is made of...
This adjustable source from 2 to 15 V uses transistors from the 60's, as indicated in the...