Johan, ik vond dit op internet, misschien kun je er iets mee.
Gr Ron.
Display not working (and no Audio) FIXED !
I Have fixed the display problem on the 780 without requiring the Service
Manual, but by using a schematic..
The 9 Volt cct that powers the display's LCD graphics (NOT the backlight, which
runs on 12 vdc) WAS NOT working. If your LCD graphics are out AND you do not get
any signal audio (you may still hear audio hiss or "screaching" though)....the
Zener diode that supplies the reference for the 9 volt cct is likly burnt out.
This Zener diode D27 is a UDZ10. It's a small surface mounted chip, close to the Q2
transistor. This diode is a 10 volt zener (not 9v, as it goes through a
resistor) UDZ10 zener. Any suitable sub should work.