We found this code key or coded keyboard in a publication from the 90s. The circuit uses components that are still common today and is powered by a 12 V voltage according to the relay used.
This circuit, for bands above 15 MHz, was found in an Argentine publication from the 1970s. The L1...
May 2017 - The new Wolfspeed 650 V Schottky rectifier diodes can now be purchased from Mouser...
The action of this circuit, found in a 1977 amateur radio documentation, is like to a delay line....