Comtech EF Data Vipersat SLM-5650A, Installation And Operation Manual

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SLM-5650A Satellite Modem
Revision 10
Front Panel Operation 7–44 MN-SLM-5650A
7.2.5.3 (TEST:) BERT
BERT: Tx:Off Pattern:2047 ErrIns
Reset Rx:Off Errs:=0000000 BER:NoSync
Use the

arrow keys to select Tx , Pattern , ErrIns , Reset , Rx , Errs , or BER . Press [ENT] . For
any option, use the

arrow keys to select the desired setting. Press [ENT] to execute the test.
BERT
Mode
Option
Description
Tx Select to turn the transmit test pattern generator On or Off.
Pattern Select from the available patterns:
• Mark – All ones.
• Space – All zeros.
•
1:1 – A one followed by a zero and then repeats.
•
1:2 – A one followed by two zero’s and then repeats.
• 2E15-1 – A pseudo-random data pattern of 2^15 –1, compatible with standard BERTs.
•
2E20-1 – A pseudo-random data pattern of 2^20 –1, compatible with standard BERTs.
•
2E23-1 – A pseudo-random data pattern of 2^23 –1, compatible with standard BERTs.
•
MIL188 – A modified pseudo-random data pattern of 2^11 –1, compatible with the MIL-188-165
test data pattern requirement of a continuous stream of 50 zero’s every 10,000 bits. This pattern
has 5 normal 2047 patterns, with the fifth patterns longest string of zero’s (11) stretched an
additional 39 bits to create a lack of transitions for 50 bits approximately every 10,000 bits.
•
2047 – A pseudo-random data pattern of 2^11 –1, compatible with standard BERTs.
ErrIns Select to insert a single error into the data stream by pressing [ENT].
Reset Select to restart the BER test and clear the error and BER displays.
Rx Select to turn on the receive bit error test set.
Errs Select to view the absolute number of errors counted.
BER Select to view the bit error rate as measured by the modem.
The BER function can work with a Fireberd supplying the transmit data test
pattern, while only turning on the Rx BER tester. The transmit test pattern
generator can be turned on at the far end of the link as long as the test
patterns match the Rx BERT. An external bit error test set can be used even
when the internal bit error test set is enabled. If AIS is enabled, the data will
be overwritten with all ones.
7.2.5.4 (TEST:) LampTest
Select LampTest to perform a diagnostic run on the front panel LEDs and VFD.