Paradyne Comsphere 3550 Series Quick Reference Manual page 12

Table 2. Model 3551 DSU Switch Settings
Switch Switch
Position Setting
(default)
S1-1 S1 1
S1-2
(default)
ON is to the rear as you face the front of the DSU.
Off is to the front.
ON Permissive V.32 DBM transmit output level of –9 dBm
Off Programmable V.32 DBM transmit level between –12
dBm and 0 dBm
ON Frame ground (FG) connected to signal ground (SG)
Off FG connected to SG through 100 ohm resistor
Function
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