Tektronix 071-0855-05 Bert Mode, Signal Source, Timing Source, Trigger Output, Active Channels

Operating Basics: User Interface

BERT Mode

For some modules a third option is available from the Signal Standard menu, the BERT mode. With this mode, the OTS9100 becomes a BERT generator. The Test Pattern selection for the active channel is the only valid selection on the transmitter signal setup page when BERT mode is selected. When the signal standard is returned to either SONET or SDH mode, the settings will return to the last settings used.

Most LED indicators are invalidated by the BERT mode. The only valid active LEDs are Signal Present, TSE, and LSS.

Signal Source

Signal Source selects the data source used as the output signal. The modes available are Internal mode and Through mode.

Internal Mode: Internal mode provides an internally-generated 9.95238 Gb/s signal with the data in a PN7 scrambled NRZ format.

Through Mode: If using through mode, the user has the choice of passing a 9.95238 GHz signal through the module in two ways, non-intrusive and intrusive. Non-intrusive will output an unmodified external signal. Intrusive allows the user to modify some aspects of the external signal as it passes through the module. To set the Overhead bytes available for overwriting, refer to the Transport Overhead or Path Overhead screens.

NOTE: As described in Getting Started, if the modules are not installed into the proper slots, Through Mode is not available as a signal source option.

Timing Source

The timing source pull-down menu selects either internal or external timing. Internal timing uses the internal clock. External timing uses the External 155 Clock In connection on the Clock Trig module.

Trigger Output

The Trigger Output allows the user to select what condition activates the output trigger. Check the appropriate box for Anomaly Trigger or Defect trigger, or activate both. The triggering on defects provides an active HIGH for each frame in which a defect is inserted. The triggering on anomalies provides an active HIGH for each frame in which an anomaly is inserted.

Active Channel(s)

The Active Channel(s) section controls the settings for signal structure and test pattern of the selected active channel(s). To set the active channel, use the up/down cursors or click the Set Channel button. When the Set Channel button is clicked, the bar for Active channel changes into an interactive menu. Type in the text box to select the channel or click Set Channel 1 to choose channel 1. If the Set All button is clicked, the Background Channels section is grayed out. Set

channel from 1 to 192 or set all.

OTS9100 User Manual 2-27