Signametrics Corporation SM4020, Руководство оператора

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ChxHi, ChxLo - These are the channel positive and negative terminals for all group channels, respectively. It starts
with Ch1Hi/Lo and ends with Ch20Hi/Lo with the 20 Channel scanners and Ch40Hi/Lo for the 40 Channel models.
Depending on the Scanner configuration, these lines are routed to the bus terminals AHi/Lo, BHi/Lo, CHi/Lo, or
DHi/Lo.
AHi, ALo - These are the A-bus positive and negative terminals respectively. The channels positive and negative
lines may be routed to these lines depending on Scanner configuration. In the Universal mode, it is also possible to
route bus pairs to other bus pairs.
BHi, BLo - These are the B-bus positive and negative terminals respectively. The channels positive and negative
lines may be routed to these lines depending on Scanner configuration. In the Universal mode, it is also possible to
route bus pairs to other bus pairs.
CHi, CLo - These are the C-bus positive and negative terminals respectively. The channels positive and negative
lines may be routed to these lines depending on Scanner configuration. In the Universal mode, it is also possible to
route bus pairs to other bus pairs.
DHi, DLo - These are the D-bus positive and negative terminals respectively. The channel positive and negative
lines may be routed to these lines depending on Scanner configuration. In the Universal mode, it is also possible to
route bus pairs to other bus pairs. It is important to note that when using the Isothermal Block the DHi and DLo
terminals should not be used, and a configuration involving them should not be selected. Therefore configurations
such as
FourGroups or SixWire should not be selected, and when selecting Universal configuration, care must be
taken not to include these terminals.
TRIG_com - This is the TRIG_in and TRIG_out return terminal. Both of these signals are referenced to it. All
three signals associated with the trigger circuitry, TRIG_com , TRIG_in, and TRIG_out are optically isolated from
the rest of the terminals in the DIN 96 connector.
Figure 3-2. The trigger input and output lines are isolated by an optical isolators.
TRIG_in - This is the trigger input signal. It requires TTL or CMOS level (at least 2.5V) to activate the trigger
input. A series 1k removes the need to add external resistor and allows direct connection to a TTL or CMOS logic
source. It is referenced to the
TRIG_com line.
TRIG_out - This is the trigger output signal. It is an open collector signal with 1k resistor in series. It will drive a
CMOS or TTL line provided it is connected to an appropriate positive supply (from 3V to 10V). It is referenced to
the TRIG_ com line.
+5V - This is a 5V supply line. It is designed to support the optional active Isothermal Block. It may also be used to
power the TRIG_out signal. When using it to power TRIG_out , it is recommended that a 10k be connected from
TRIG_out to it as in Figure 3-3. This supply may vary between 4.7V to 5.7V, and its usage should be limited to no
more than 10mA. This supply is isolated from the rest of the signals in the DIN 96 connector. This signal is
referenced to the
Common line.
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