I'm trying to repair a baseball pitching machine motor speed control board for a friend. The circuit is based on this schematic, but has an LM723 added in, probably for more precise control of the unijunction transistor.
http://www.next.gr/automations/motor-control-circuits/High-torque-motor-speed-control-l12852.html
This is a graphic from an old Motorola application note on using a unijunction transistor and SCR's to implement a phase control circuit for running a DC motor off the AC power line. Does anyone have the original note or a link?
Thanks.
ak
http://www.next.gr/automations/motor-control-circuits/High-torque-motor-speed-control-l12852.html
This is a graphic from an old Motorola application note on using a unijunction transistor and SCR's to implement a phase control circuit for running a DC motor off the AC power line. Does anyone have the original note or a link?
Thanks.
ak