Operating Basics: User Interface
2-32 OTS9100 User Manual
Through Mode
When using through mode, a number of the overhead bytes may be overwritten as the external
signal passes through the card. This is done through the use of the Through Mode selections
available in the Overhead menu, as shown in Figure 2-13. If the box is checked for Regenerate
B1/B2 Parity, the receiver will recalculate the B1/B2 parity and insert the new information into
the overhead as the signal is passed through the card. To disable B1/B2 parity regeneration,
ensure that the Regenerate B1/B2 Parity box is not selected.
Figure 2-13: Through Mode Overwrite menu
To overwrite an incoming byte, click in the box beside the selection under the Overwrite
Incoming heading. If you wish to keep a byte from being overwritten, make sure the box beside
the selection is not selected. The bytes available to be overwritten are J0 Trace/C1 Byte, E1, F1,
D1..D3 Section DCC, K1..K2 APS, D2..D12 Line DCC, S1 Sync Status, M1, Z2, and E2. Parity
regeneration is always enabled if the user chooses to overwrite any incoming Overhead bytes.
NOTE: There is no explicit byte edit for M1. Checking the M1 overwrite setting provides the ability
to insert REI-L.