JPS RTU-292C, Инструкция по установке и эксплуатации

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RTU-292C Operations Manual
2-6
2.8
CONFIGURING THE RTU-292C
The RTU-292C factory default settings are listed in Table 2-1. The factory set-up will be correct
for most installations; explanations of each feature selection method or other adjustment are
provided for systems requiring different set-ups. If any setting must be changed, refer to Figure
2-3
Location of Internal Option Settings”. Remove the top cover of the unit by removing the
Phillips-head screws around its edges.
NOTE:
Many of the RTU-292C's operating parameters are set by internal eight-position
dipswitches SW1 and SW2. These switches are read by the RTU-292C
microprocessor only when the unit power is turned on. To change any dipswitch
controlled parameter, turn off the RTU-292C, change the switch setting(s), and then
turn the unit power back on.
2.8.1 PROGRAMMING MODE SETUP PARAMETERS
Some of the RTU-292C setup options are selected by entering DTMF commands by a connected
telephone. Since these parameters are set after a connection is made, they are detailed in Section
3. See Table 3-2, “Programming Mode DTMF Commands”.
2.8.2 SETTING TELEPHONE SEND AND RECEIVE LEVELS
The levels of the audio signal that are sent into (Send) and received from (Receive) the telephone
line are adjustable via SW2 switches 1 through 3 on the RTU-292C Main Board. The levels are
adjustable from -21 dBm (600 Ohm) to 0 dBm in 3 dB steps. The dipswitches simultaneously
set the Send and Receive levels.
Table 2-3 Recommended Phone Line Settings
Type of System Send & Receive Levels
Dial-Up lines in a U.S. Domestic phone system -9 dBm
Dial-Up lines in most non-U.S. telephone systems -9 dBm
PBX Systems -12 dBm
Field Wire not connected to a telephone network -6 dBm
When using the RTU-292C in a domestic U.S. dial-up telephone network, the MAXIMUM level
allowed into a telephone line at the subscriber end is -9 dBm. Putting more level into the line
than this will NOT increase performance, but will result in distortion, crosstalk into other circuits
and the telephone company may disconnect the call. When operating into a PBX system, the
level should be set at -12 dBm. Higher levels than these may be only used into field wire or
dedicated or private lines that are KNOWN to accommodate higher levels.