Kodak Ektapro Slide Projector 4020 - Manual (Page 47)

LAMP Control
a) Dual LAMP Operation
All Models are equipped with a DUAL LAMP MODULE (Extra Bright).
The POWER REGULATION PCB on all Models contains a LAMP current circuit that can detect if the active
LAMP is on, indicated by a LED on the BACK PANEL.
If a LAMP fails, the MICROCONTROLLER receives the LAMP_CURR signal from the POWER REGULATION
PCB. It activates the MIRROR MOTOR and moves the MIRROR to the second LAMP position. Then the relay
K1 is energized and second LAMP is energized. The MICROCONTROLLER also energizes the LED for the
second LAMP. The LED’s are located on the BACK PANEL.
The Models 4020 - 9020 and 9020/CINE have a memory. This memory is storing the the current used lamp as
long as the lamp is defective. That means the mirror of the DUAL LAMP MODULE do not change his position
after a new lamp is inserted. This function can be disabled (see page 2-3).
The characteristic of the lamp curve is no longer generated by a PLL circuit on the MASTERBOARD. Up to
now it is stored in the Software LAMP Control memory and the TRIAC will be triggered from the
MICROCONTROLLER.
Zero-Cross
Circuit
M Mirror
Motor
Dissolve
Logic
Relay
Mirror
Motor
Driver
Micro
Controller
Master Board
Dual Lamp
Modul
Power Regulation Board
91VAC
Lamp Current
Detection and
Switch off
Relay
Driver
L1 L2
Zero_Cross
DATA
SYNC
Lamp_curr Lamp
Current
Relay
Driver
Economy
82VAC
Software
Lamp
Control
SOFTWARE TRIGGER
GND
figure 3-9
SM 2547-1 Service Manual
Kodak AG, Stuttgart 3-11 03/98