Grundig Satellit 500 Radio LED upgrade

Discussion in 'Technical Repair' started by JMark, Jan 16, 2018.

  1. JMark

    Thread Starter New Member

    Mar 3, 2014
    HI Guys, I hope I posted this in the correct place. I need a little help. I'm working on a vintage Grundig Satellit 500 radio. I'm replacing the incandescent lamps with LED, there are three lamps (marked LA1, LA2 and LA3 on the diagram). Two for the LCD display and one lamp to illuminate the keypad. I can't seem to get this correct.

    The radio is supposed to function like this: When operating on batteries each press of the keypad will illuminate the LCD and keypad for ten seconds. When operating on mains the LCD and keypad will remain illuminated constant whether the radio is powered on or off.

    I must have the wrong size or placement of the resistors. I'm getting erratic behavior from the set (relating to the lamps), too much to go over here. Attached is the related schematics. If anyone has some thoughts on this I'd appreciate it. Thanks! John

    ET43.png View attachment 143777 ET41.png
    Last edited: Jan 16, 2018