Used by radio amateurs to accompany telegraphic transmissions, this circuit generates an audio tone. The power comes from the transmitted RF signal itself.
An oscillator whose frequency can be adjusted between 500 Hz and 5 kHz with the use of a...
This circuit was found in Motorola documentation from 1969. The transistors are from that time. The...
This circuit brings together in a single set a preamplifier and an equalizer with several inputs. The...