Dsr Jumper; Ch_Gnd Jumper; 422 Model 422 - Canoga Perkins 2240 User Manual

4.2.4 DSR Jumper

The DSR jumper controls the behavior of the DSR signal. The EIA position
causes the DSR to turn OFF in certain test conditions when the transmit data is
blocked and has no end-to-end or loopback path. This condition exists when the
far-end 2240 modem has a local loopback active. The TEST position causes DSR
to turn OFF (negate) whenever any loopback is active at one or both modems.
Factory Setting = EIA

4.2.5 CH_GND Jumper

The jumper selects whether chassis ground is connected directly to signal ground
(SHORT position) or through a 100 Ohm resistor (100_OHM position).
NOTE: In the standalone model, the 100_OHM position will only
put a 100 Ohm resistor between the two grounds if the 2240's main
board SIGNAL GND jumper is set to the FLOAT position.
When installed in the 2201 Rack Chassis, any modem main board,
interface, or rack chassis jumper being set to SHORT will override
the FLOAT and 100_OHM positions on all of the other modems.
CONSIDER THIS JUMPER CAREFULLY.
Factory Setting = 100_OHM
4.3 RS-449 / 422 Model 422
This interface complies with EIA Standard RS-449. Electrical characteristics
comply with RS-422 for clock and data signals and RS-423 for control signals.
The RS-449 / 422 interface applies the physical connector type and pinouts
specified in RS-449 (refer to Table 4-B). The interface uses a 37-pin, female D-
type connector for the physical connection.
2240 Fiber Optic Modem
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