Comtech EF Data RCS20 - Manual (Page 84)

RCS20 M:N Redundancy Switch Revision 15
User Interfaces MN-RCS20 and CD-RCS20
4–50
4.3.2.25 RDM FALLBACK CONFIGURATION
This screen allows the user to configure the fallback programming for the optional Reference Distribution
Module (RDM). The RDM has two reference inputs (EXTA, EXTB) and an internal frequency source
(INT). The fallback programming allows automatic switching between these three frequency sources.
There are clock activity detectors on each frequency source, and automatic switching (fallback) will occur
if there is no activity for the current frequency source. The following fallback modes are available:
EXTA ONLY INT ONLY
EXTA  INT INT  EXTA
EXTA  EXTB EXTA  EXTB  INT
INT  EXTA  EXTB
For these modes, the system will switch to the leftmost source that has clock activity. For example, if the
fallback mode is EXTA  EXTB  INT, and there is no activity on EXTA or EXTB, then the INT source
will be selected. If activity returns to EXTB, then EXTB will be selected, and if activity returns to EXTA,
then EXTA will be selected.
4.3.2.25.1 Programming steps:
1. Press to change the displayed fallback mode.
2. Continue pressing until the desired fallback mode is displayed.
3. Press or to abort programming (no switch parameters changed).
4. Press to load the information on the screen into the switch parameter table.
Key Label Function
S1 TOG MODE Cycle through the above listed fallback configurations.
S2 --- N/A
S3 --- N/A
S4 RETURN Cycle back to the REFERENCE DISTRIBUTION CONFIGURATION Screen.
Numeric Keypad ---
Press or to abort programming (no parameters changed).
Press to load the information on the screen into the switch parameter table.
RDM INTERNAL REFERENCE CONFIGURATION
FALLBACK : EXTA ONLY
TOG MODE RETURN