MN/U-KST12000 Rev. 0
6–1
Chapter 6.
MAINTENANCE
6.1 System Checkout
6.1.1 General
The system checkout Section is to be used as an aid in setting up a modem within the
earth station. There are tables for use in checking to see if the Eb/N0 is correct, typical
output spectrum, and typical eye pattern and constellation pictures.
6.1.2 Modulator Checkout
The modem supplies a QPSK modulated result of the DATA I/O connector to the IF
output connector (CP1). A typical output spectrum is shown in Figure 6-1. If the output
does not resemble this picture refer to the fault isolation in Section 6.2.1 to locate the
problem.
The first Step in turning up a carrier is to set the output frequency. This is done in the
“CONFIG” menu on the front panel (Sections 3.1.4. and 3.2.1). The “CONFIG” menu
also allows the operator to set the output level, turn the output ON or OFF, set the
scrambler, differential encoder, clock source, and gives access to the test modes for
system check out. Available test modes are RF loopback, BB loopback, and CW mode.
After the output frequency and level is set the output is to be turned ON.
6.1.3 Demodulator Checkout
The demodulator supplies baseband data to the DATA I/O connector that is a result of
the QPSK modulated signal input at the IF input connector (CP2). Clock and data are
recovered, decoded, and descrambled from the input RF signal by the demodulator and
decoder cards.
The input to the demodulator card must be set within the proper frequency and power
level for the demodulator to lock to the signal. Refer to Figure 6-2 and Table 6-1 to
check for proper Eb/N0 level. Figure 6-2 is an example of a 3/4 rate carrier operating at
Summary of Contents for SDM-309B
Page 7: ...Preface SDM 309B Satellite Modem iv Rev 0 This page is intentionally blank ...
Page 13: ...Table of Contents SDM 309B Satellite Modem x Rev 0 This page is intentionally blank ...
Page 16: ...SDM 309B Satellite Modem Introduction MN U SDM309B Rev 1 1 3 Figure 1 1 SDM 309B Modem ...
Page 18: ...SDM 309B Satellite Modem Introduction MN U SDM309B Rev 1 1 5 Figure 1 3 Modular Construction ...
Page 25: ...Introduction SDM 309B Satellite Modem 1 1 12 MN U SDM309B Rev ...
Page 28: ...SDM 309B Satellite Modem Installation MN U SDM309B Rev 2 2 3 Figure 2 1 Rear Panel View ...
Page 34: ...SDM 309B Satellite Modem Operation MN U SDM309B Rev 3 3 Figure 3 1 Front Panel View ...
Page 47: ...Operation SDM 309B Satellite Modem 3 16 MN U SDM309B Rev Figure 3 2 Menu Tree ...
Page 48: ...SDM 309B Satellite Modem Operation MN U SDM309B Rev 3 17 Figure 3 3 Menu Tree ...
Page 49: ...Operation SDM 309B Satellite Modem 3 18 MN U SDM309B Rev Figure 3 4 Menu Tree ...
Page 50: ...SDM 309B Satellite Modem Operation MN U SDM309B Rev 3 19 Figure 3 5 Menu Tree ...
Page 51: ...Operation SDM 309B Satellite Modem 3 20 MN U SDM309B Rev Figure 3 6 Menu Tree ...
Page 52: ...SDM 309B Satellite Modem Operation MN U SDM309B Rev 3 21 Figure 3 7 Menu Tree ...
Page 53: ...Operation SDM 309B Satellite Modem 3 22 MN U SDM309B Rev Figure 3 8 IF Loopback ...
Page 54: ...SDM 309B Satellite Modem Operation MN U SDM309B Rev 3 23 Figure 3 9 RF Loopback ...
Page 55: ...Operation SDM 309B Satellite Modem 3 24 MN U SDM309B Rev Figure 3 10 Interface Loopback ...
Page 56: ...SDM 309B Satellite Modem Operation MN U SDM309B Rev 3 25 Figure 3 11 Baseband Loopback ...
Page 71: ...Operation SDM 309B Satellite Modem 3 40 MN U SDM309B Rev Figure 3 12 Menu Tree ...
Page 72: ...SDM 309B Satellite Modem Operation MN U SDM309B Rev 3 41 Figure 3 13 Menu Tree ...
Page 73: ...Operation SDM 309B Satellite Modem 3 42 MN U SDM309B Rev Figure 3 14 Menu Tree ...
Page 74: ...SDM 309B Satellite Modem Operation MN U SDM309B Rev 3 43 Figure 3 15 Menu Tree ...
Page 75: ...Operation SDM 309B Satellite Modem 3 44 MN U SDM309B Rev Figure 3 16 Menu Tree ...
Page 76: ...SDM 309B Satellite Modem Operation MN U SDM309B Rev 3 45 Figure 3 17 Menu Tree ...
Page 77: ...Operation SDM 309B Satellite Modem 3 46 MN U SDM309B Rev ...
Page 88: ...SDM 309B Satellite Modem M C and Interfaces MN U SDM309B Rev 4 4 11 Figure 4 4 IBS Fault Tree ...
Page 89: ...M C and Interfaces SDM 309B Satellite Modem 4 4 12 MN U SDM309B Rev Figure 4 5 Jumper Table ...
Page 127: ...SDM 309B Satellite Modem Theory of Operation MN U SDM309B Rev 5 5 3 Figure 5 1 Modulator Card ...
Page 151: ...Maintenance SDM 309B Satellite Modem 6 6 6 MN U SDM309B Rev Figure 6 3 Typical Eye Patterns ...
Page 177: ...SDM 309B Satellite Modem Data Rates and Filters MN U SDM309B Rev A 9 ...
Page 235: ...External Channel Unit SDM 309B Satellite Modem C C 28 MN U SDM309B Rev Figure C 13 Menu Tree ...
Page 236: ...SDM 309B Satellite Modem External Channel Unit MN U SDM309B Rev C C 29 Figure C 14 Menu Tree ...
Page 237: ...External Channel Unit SDM 309B Satellite Modem C C 30 MN U SDM309B Rev Figure C 15 Menu Tree ...
Page 238: ...SDM 309B Satellite Modem External Channel Unit MN U SDM309B Rev C C 31 ...
