January 2016                                                                                                               Page 6–7
Chapter 6. Testing Facilities
6
6.4 Performing Checkback
Tests/Functions
The  Checkback  system's  primary  function  is  to
perform checkback tests, verifying that your carri-
er communication path is operating. You can per-
form checkback tests in several ways:
• Manual  request  from  the  front  panel  test
menu
• Manual request from the checkback page
• Manual request from an external source via
an input set for “Checkback Initiate”
• Automatic test 
• Automatic carrier recovery test
• Automatic remote-initiated tests 
The Checkback system also does other secondary-
functions  such  as  turning  on  remote  transmitters
and getting data from distant UPLC-II™ units.
6.4.1 Manual Requests from Web
Pages
By clicking on the left-hand navigator
“Checkback” button and using the 3 pull-down
menus, you can do the following:
A. Tests
1. Run manual checkback test
2.  Run  loopback  test  to  turn  on  remote
t
ransmitter only
B. Clear Module
1. Clear recovery mode 
      (also clears delayed alarm)
2. Clear alarms
3. Clear checkback events counts
C. Checkback (Communications)
1. Update status of web page
2. Connect to distant UPLC-II™ to view;
      • Home page
      • Settings
      • Partial SOE Log
6.4.2 Loopback Test Capability (Turn
On Remote Transmitter via the
power line)
You can command a distant Automatic checkback
system  to  key  its  carrier  for  a  specified  duration
(e.g.,  30  seconds),  giving  you  time  to  measure
your local receiver's level. This is called loopback
tests  in  the  UPLC-II™  and  they  are  always  per-
formed  at  both high and low power.  If  loopback
duration  is  set  to  30  seconds,  the  carrier  is  first
keyed  on  high  power  for  30  seconds,  then  low
power for 30 seconds. 
Figure 6–2. Example of the Checkback Page (ON/OFF Mode)