Nautel NG1000, Troubleshooting Manual

Page: 42 / 164

NG1000 Troubleshooting Manual Responding to alarms
Page 1-20 Issue 0.4 2010-10-12
Exciter/Control PWB Replacement
See Figure
MD-5
(top view) in the Mechanical Drawings section (Section 6) of this manual.
1. Disconnect the associated VHF transmitter’s (A or B) ac power source, disconnect all
cabling from the rear of the transmitter and remove it from the system cabinet.
2. Place the VHF transmitter - top side up - on a suitable work surface. Remove the
transmitter’s top cover, noting it is secured using M3 screws.
3. Disconnect all mating plugs from the exciter/control PWB (A1). Remove the D-sub
connector’s securing screws using a 5 mm socket (Nautel Part # HAS80, provided in the
ancillary kit).
4. Remove the six M3 screws that secure the exciter/control PWB (A1) to the transmitter.
Retain hardware.
5. Remove the exciter/control PWB from the VHF transmitter.
6. Locate or obtain a replacement exciter/control PWB (Nautel Part # NAPE82). Reverse
Step 1 through Step 5 to reinstall the new exciter/control PWB. If necessary, refer to
Table 3.7 on page 3-6 for connector mating details for A1.
7. Refer to the Calibration procedures in the “Operating the Transmitter” section of the Operations
and Maintenance Manual and perform the appropriate transmitter’s 10 MHz calibration
procedures as well its preamp/IPA bias routine. The transmitter should resume normal
operation and any associated alarms should clear.
NOTE:
The exciter/control PWB is static sensitive and must be handled in a static protected manner.