Ttl / Bnc Interface Model -Bn; Bnc Connectors - Canoga Perkins 2240 User Manual

Figure 4-4.

BNC Connectors

4.8 TTL / BNC Interface Model -BN

This model uses BNC (bayonet) connectors for the physical interface. The electrical
signal characteristics are unbalanced TTL levels, with only the clock and data
circuits supported. Four BNC connectors are supplied for connection to a DTE
device.
High speeds and long distances (clock and data only) can be achieved using this
interface.
This interface version has a switchable dual purpose port for the Send Timing (SCT)
and Terminal Timing (SCTE) clock signals. A two-position slide switch (S1) on the
interface card controls the port direction.
When the switch is set towards the BNC connectors, the port is configured as an input
(for the SCTE clock). Sliding the switch away from the BNC connectors configures
the port as an output (for the SCT clock). (See Figure 4-4 for connectors and refer to
Table 4-O for signals supported.)
NOTE: When setting up the clock select, the proper main circuit board
clock mode must be set correctly, i.e., external for the SCTE clock input,
slave or internal for the SCT clock output.
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