This circuit was found in a documentation of the 80s, having didactic purpose. For R1 values between 10k to 1M can be used. Transistors are general purpose types.
This circuit found in a 1964 US publication reverses the signal level by providing 9 to 0 V...
This circuit is from 1967 General Electric documentation. It uses SUS which are not very common...
August 2017 - MCUs of the new Infineon MC1400 series for industrial use can now be purchased from...