Specifications

3-4
3.3.3 Connection of Solar Cell Boards
In contrast to traditional solar cells, the Cat. No. 655 and other solar cell circuit
boards used by several projector manufacturers are active devices with their own
power supply. Some care needs to be given to the wiring between the board and the
CP500 in order to avoid grounding problems and to provide immunity to RF
interference. In principle, this means separating the audio ground connections and
the RF shielding screen connections.
The 0V point (audio ground) must be connected from the basement reader card to
the CP500 by a separate wire (or wires) along with the audio signal wires. The
cable shield (screen) must be kept separate from the audio ground connections. It
must be connected only to the chassis or enclosure of the equipment at each end.
The following diagrams (Figures 3-2 and 3-3) show two connectors on the board.
The three pin connector, J1 is used for the power supply. The signal output
connector J2 provides six output pins; two each for the "balanced" left and right cell
outputs, and two 0V audio ground connections.
NOTE:
The following tables show the Right channel appearing on pins 1, 2, and 3 of the 6-pin connector J2.
The physical orientation of the board mounting in the projector and the orientation of the connector body
mounting on the board affect which channel appears on which pins of the connector.
Be aware that pin
allocations for the channels will vary depending on mounting arrangements of the board and
connector
. The J2 connector pin solder hole with a square outline is pin 1.
J2 Pin Number Signal
OR:
J2 Pin Number Signal
1
Right
+
1
Left
-
2 Signal Ground 2 Signal Ground
3
Right –
3
Left
+
4
Left
+
4
Right
-
5 Signal Ground 5 Signal Ground
6
Left
–
6
Right
+
There must be a connection between the ground pins at the Cat. No. 655 solar cell
circuit board and the audio common in the CP500. This connection must
not
use
the shield of the optical input cable, otherwise RF energy can be imposed on the
CP500 ground system.
Pin numbers 6 and 9 of each 9-pin D connector ("Projector") on the CP500 allow
these connections to be made. The wire that connects either of these pins to the
Cat. No. 655 audio ground should pass inside the same shield as the optical input
cables and not connect with the shield at any point.