This relay shield circuit for old computers was found in January 1983 Radio Electronics magazine. The relays are sensitive types with currents up to 200 mA.
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...