
3-79
Performance Tests
SDH Frequency Offsets (Options US1, [US5], A1T, [A1U], A3R [A3S],
120)
SDH Frequency Offsets (Options US1, [US5], A1T,
[A1U], A3R [A3S], 120)
Specifications
Description
The SDH Transmitter Offset Clock is checked for range and accuracy using a
Frequency Counter to measure the STM-1 Data rate. This gives an indirect measure
of the transmitter clock frequency as the data is clocked by the internal 10MHz
clock oscillator. A measurement with no offset is performed to establish a reference
Clock frequency. The frequency accuracy is then measured over the specified offset
range. The STM-1 Framing is disabled during this test using the
function of the HP 37717C.
Equipment Required
Procedure
1. Recall the HP 37717C DEFAULT SETTINGS as shown on 3-2.
2. Connect the STM-1 OUT port to the Frequency Counter terminated in 75
Ω
(use
the T connector).
Range
±
999 ppm
Resolution
0.1 ppm
Accuracy
0.02 ppm (from 0 to
±
100 ppm)
0.2 ppm (from
±
100 to
±
999 ppm)
MODULE DEBUG
Frequency Counter
: HP 5335A Opt 010
T Connector
: HP 1250-0781
Summary of Contents for 37717C
Page 2: ...HP 37717C Communications Performance Analyzer Calibration Manual ...
Page 5: ...2 ...
Page 21: ...xviii Contents ...
Page 109: ...2 20 Installation Additional Precautions for Service Engineers ...
Page 312: ...3 203 Performance Tests Trigger Output Option UKZ Figure 3 57 Monitor Input Test Setup ...
Page 375: ...3 266 Performance Tests Performance Test Record ...
Page 379: ...4 4 Installation Current Previous Terminology ...
Page 392: ...B 9 Appendix B Fitting Calibrating Testing New Modules Typical Jitter Transmit Spectrum ...
Page 393: ...B 10 Appendix B Fitting Calibrating Testing New Modules ...