10
Table 2. Model 3551 DSU Switch Settings
Switch
Position Switch
Setting Function
S1 1
ON
(default) Permissive V.32 DBM transmit output level of –9 dBm
S1-1 Off Programmable V.32 DBM transmit level between –12
dBm and 0 dBm
ON Frame ground (FG) connected to signal ground (SG)
S1-2 Off
(default) FG connected to SG through 100 ohm resistor
ON is to the rear as you face the front of the DSU.
Off is to the front.