Hello everyone.
I'm trying to fix the projector from the title. When I got it, it was stuck in power-boot. Fortunately, the faulty component was losing its magic smoke and managed to find it almost immediately ( a SMD cap ).
After I replaced it, the projector started to show signs of life - LEDs staying lit, fans turning on when the power button pressed, color wheel turning... but no light.
On the input of the ballast, the expected V is present, but on the output - nada.
Just to mention - the PSU has no stand-by mode. All rails are present - 2.69V, 11.9V, 5.07V ( values when the unit is ON ) + the high ballast voltage, as soon as it is plugged in the socket.
I found the pinout of the ballast control cable from another model and managed to start it, by shortening pin 1 and 2. So the ballast starts with little hesitation, but after that works without any porblems. The HG lamp seems to be working also fine. Unfortunately, this workaround works only in "stand-by" mode. Several seconds after I press the power-on button and the fans start to spin, the ballast turns-off ( even with the shorted pins ).
The control cable ends(?) with 3 optocouples. The Voltages on the pins are:
no ballast
stand-by -> on
1 - 4.7 -> 5
2 - 0 > 0
3 - 4.7 -> 5
4 - 0 -> 0
5 - 0 ->0
with ballast
stand-by -> on
1 - 4.7 -> 5.0
2 - 0 -> 0
3 - 4.7 -> 5.0
4 - 4.0 -> 4.3
5 - 4.0 -> 4.3
This is my first projector repair at this level, so I'm really not sure how to proceed...
I'm trying to fix the projector from the title. When I got it, it was stuck in power-boot. Fortunately, the faulty component was losing its magic smoke and managed to find it almost immediately ( a SMD cap ).
After I replaced it, the projector started to show signs of life - LEDs staying lit, fans turning on when the power button pressed, color wheel turning... but no light.
On the input of the ballast, the expected V is present, but on the output - nada.
Just to mention - the PSU has no stand-by mode. All rails are present - 2.69V, 11.9V, 5.07V ( values when the unit is ON ) + the high ballast voltage, as soon as it is plugged in the socket.
I found the pinout of the ballast control cable from another model and managed to start it, by shortening pin 1 and 2. So the ballast starts with little hesitation, but after that works without any porblems. The HG lamp seems to be working also fine. Unfortunately, this workaround works only in "stand-by" mode. Several seconds after I press the power-on button and the fans start to spin, the ballast turns-off ( even with the shorted pins ).
The control cable ends(?) with 3 optocouples. The Voltages on the pins are:
no ballast
stand-by -> on
1 - 4.7 -> 5
2 - 0 > 0
3 - 4.7 -> 5
4 - 0 -> 0
5 - 0 ->0
with ballast
stand-by -> on
1 - 4.7 -> 5.0
2 - 0 -> 0
3 - 4.7 -> 5.0
4 - 4.0 -> 4.3
5 - 4.0 -> 4.3
This is my first projector repair at this level, so I'm really not sure how to proceed...
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