3 digit segmentation, 4 schematic, 5 troubleshooting – Daktronics CH-1018H User Manual
Page 20: Digit segmentation -2, Schematic -2, Troubleshooting -2

Maintenance & Troubleshooting
3-2
The lamp driver has 22 connectors, providing power and signal inputs and outputs to digits.
The functions of these connectors are as follows:
Connector Number
Function
1-16
Outputs to digits
17 Signal
Input
18
Power input for outputs 1-8 (120 V)
19
Power input for driver logic and fan (120V)
20
Power input for outputs 9-16 (120V)
24
Dim option selector
In Drawing A-51511, the numbers on the digits refer to the lamp driver output connector
wired to each digit.
3.3
Digit Segmentation
Reference Drawing: Segments, 4x7 Lamp Matrix Digit.................. Drawing A-37685
In a digit certain lamps always go on and off together. These groupings of lamps are known
as "segments". Each digit has eight segments, referred to by letters A through H. Drawing
A-37685 illustrates these segments and shows which connector pin and wire color is wired to
each segment.
3.4 Schematic
Reference Drawings: Driver Enclosure, Power & Signal ............... Drawing A-37915
Schematic, Pwr & Sig, CH-21GP ................ Drawing A-38788
The schematic diagram in Drawing A-38788 shows the power and signal inputs into the
display and to the lamp driver. The component numbers correspond to those shown in
Drawing A-37915 in Section 2.
3.5 Troubleshooting
This section lists some symptoms that may be encountered with the CH-1018H display. For
these symptoms, possible causes and corrective actions are indicated. This list does not
include every possible problem, but does represent some of the more common situations that
may occur.
Observed Problem
Possible Cause
One lamp won’t light
• Burned-out lamp
• Broken wire behind digit
Digit segment won’t light
• Broken wire
• Poor contact at driver connector
• Internal driver malfunction
Entire digit won’t light
• Broken wire (black)
• Poor contact at connector, pin 7
• Fuse blown in driver
Half the display won’t light
• Service breaker tripped