UJT for SCR AC to DC rectificer help

Discussion in 'General Electronics Chat' started by whywhy68, Jun 12, 2008.

  1. whywhy68

    Thread Starter Member

    Jun 11, 2008
    i am doing a SCR AC to DC rectificer of 220V 50hz sine input

    so if i wan to use a UJT relaxation osciliator to fire the SCR, do i need to fixed the frequency of the osciliator to 50 hz as well ? if yes, then f = 1.44/RC , what abt the firing angle ? is it control by varying the Rb1 or Rb2 resistance value while keeping the osciliator frequency at 50hz
  2. beenthere

    Retired Moderator

    Apr 20, 2004
    Last edited: Jun 12, 2008