2002 by ELTRA GmbH Germany – January 2002 – Service Manual OH 900 / ON 900 / ONH 2000
3.3-1
3.3
3.3
Infrared electronics
The complete signal processing for all channels is handled through the circuit
board IR21. In the event of a failure, the entire circuit board should be exchanged.
The plugs ( 1 / 2 / 3 / 4 ) should be unplugged.
The 10 screws ( 6 and 7 ) should be removed.
On the IR21 - circuit board, no adjustment is needed. You should, however, check the
adjustments on the infrared cell, as in 2. 3.
The IR21-circuit board is malfunctioning, when the correct signal can be measured at
test point 1; while the signal at test point 6 cannot be adjusted to zero, see 2. 3.
2
3
4
5
2
3
4
5
2
3
4
5
2
3
4
5
2
3
6
5
06005
ELTRA-IR21
4 3
4
2
TP1 TP1
TP1
1
1
1
TP6
TP7 TP6
TP7
TP6
TP7
3-3