Restart Key; Test Mode Key - Fluke 635 User Manual

2-15. RESTART Key

Bit errors, BPV errors, CRC errors, frame errors, clock slips, and errored
seconds are cleared to "0" when the RESTART key is pressed. If one of these
results is being displayed when the RESTART key is pressed, it will continue
to be displayed, but "0" will be displayed until an error of that type occurs.
Any red Error LEDs that are flashing (to indicate errors of that type) will be
turned off when the RESTART key is pressed. All Status and History LEDs
are cleared when the RESTART key is pressed.
Always press the RESTART key after connecting the test set to the
line under test. The unit might detect invalid errors when first
connected due to receiver sensitivity.
Pressing the RESTART key does not affect the Signaling Bits LEDs, Data
Bits LEDs, Signaling Type LEDs, LOW BATTERY LED, or Channel
Selection display. In addition, pressing the RESTART key causes the test set
to enter the auto-evaluate mode (see section 3-2 for additional information on
automatic evaluation).

2-16. TEST MODE Key

The TEST MODE key allows you to select one of three test modes: T1, F64
(fractional T1, 64k), or F56 (fractional T1, 56k). When the T1 mode is
selected, you can perform a T1 in-service or out-of-service BERT. For both the
F64 and F56 test modes, the receiver performs T1 in-service or out-of-service
testing on only the active channels and ignores the data on all other channels.
When F64 mode is selected, all 8 bits in each active channel are used by the
receiver for BERT. When the F56 mode is selected, only the first 7 bits in each
active channel are used by the receiver for BERT.
The transmitter (QuickBERT-T1 only) sends the BERT pattern on the active
channel(s). The received signal is simply passed through in the inactive
channels and if there is not a received signal present, the inactive channels are
filled with idle code (FF Hex). (Channels can be selected with the FT1
CHANNEL SELECT key.)
Note
Overview
2
Controls
2-11