HP 37717C Calibration Manual page 51

General Information
Specifications
either channel. The data may be
dropped/inserted MSB or LSB first.
The data rate for access is: 192 kb/s
(SOH DCC), 576 kb/s (LOH DCC).
Optical interface stress test:
2 to 259 bytes of the payload are
overwritten with a block of zeros or
ones after scrambling. Alternatively the
ITU-T G.958 CID (consecutive
identical digits) test can be selected.
Tributary scan: Automatically test
BER on each SONET tributary for error
free operation.
Rx setup is used to determine tributary
structure and test pattern.
Alarms: Pattern loss.
Test time: Fully user selectable.
User selectable bit error threshold: Off,
> 0, 10-3, 10-6.
Mixed payloads: Each STS-1 SPE
within an STS-3 can be independently
configured to contain a STS-1 SPE user
word, VT2 or VT1.5 structure.
Keep alive signals: DSn/PDH:
Transmit last configured SONET signal
while transmitting a DSn/PDH signal.
Thru mode
Transparent thru mode:
The signal is passed through the
instrument without being altered for
monitoring purposes where no
protected monitor point is available.
Overhead overwrite thru mode:
In addition to the above, the test
features associated with the TOH and
POH can be enabled to control one
single- or multi-byte overhead channel
1-30
(i.e. errors and alarms, optical stress
test, overhead sequences, APS
messages, DCC insert, overhead BER.
Full Rx functionality also available).
STS-3c/STS-1 SPE overwrite
thru mode: In addition to both of the
above, overwrite the complete SPE
with the internally generated payload.
This enables the TOH to be looped
through while a new payload is
inserted. All of the test features which
affect the SPE and/or the POH are
enabled (i.e. errors and alarms, adjust
pointer, overhead sequences, APS
messages, overhead BER. Full Rx
functionality also available).
Tributary overwrite thru mode:
When the payload passing through the
instrument contains a VT structure, thru
mode it will be possible to choose a
single VT to be overwritten, as opposed
to the complete payload. All of the test
features which affect the VT and/or the
POH are enabled (i.e. errors and
alarms, adjust pointer. Full Rx
functionality also available).
STS-3 and STS-1 receiver
functions
STS-3 receive input
Equalization: Automatic for cable loss
up to 12 dB at half the bit rate.
Monitor point compensation:
Monitor mode conforms to ITU-T
G.772. Monitor gain 20 to 26dB.
STS-1 receive input