Harris ZX2500, Technical Manual

Page: 118 / 198

5-14 888-2595-001 12/20/11
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WARNING: Disconnect primary power prior to servicing.
Section 5 Maintenance and Alignments
ZX Series
STEP 4
Check readings at test points on controller board with voltmeter and
compare to factory test data report. Log results for future reference.
a.
IPA CURRENT: in general should be < 12A
b.
MAX LOAD TEMP: in general should be below .6V for a 25C
ambient temperature. See Table 5-2 for scale conversion to degrees
centigrade.
c.
MAX PA TEMP: in general should be below .6V for a 25C ambient
temperature. See Table 5-3 for scale conversion to degrees centi-
grade.
d.
PA BIAS: should be either 0V or near -5V depending on module
type
1.
IBOC modules: -5V in FM mode, 0V otherwise
2. FM modules: 0V
e. IPA bias: should be near 0V…-1V depending on internal vs. exter-
nal power control
1. With exciter power control: 0V
2.
With internal power control -0V to -15V, -1V if at full power on
POWER RAISE/LOWER control.
STEP 5
If front panel STAUS LED is not green, perform following checks inside
amplifier chassis and consult Section 6 – Troubleshooting for suggestion
as to how to proceed.
a.
Check alarm LEDs on controller card.
b.
Check status of PA(PS) ON lights on PS modules.
c.
Check status of IPA ON LEDs inside IPA heatsink.
d.
Check status of red LEDs behind each PA module.
STEP 6
Procedure complete.