We found this Vox in a 1969 Motorola documentation. Transistors support modern equivalents and the SCR can be a TIC106. The reset is done by a push button.
We found this circuit in an Australian publication from 1991. It is a kit of the time with input...
With this circuit it is possible to monitor a signal that is being recorded on an old tape...
This CW circuit was found in a Radio Amateur Today from the 890s. The CMOS circuit must be powered by...