Table of Contents
Advertisement
633/635
Users Manual
2-57. TX FRAME Key (QuickBERT-T1 only)
Four possible framing selections are available with the QuickBERT-T1
(NONE, D4, ESF, SLC96). If NONE is selected, the QuickBERT-T1 will
transmit the selected pattern unframed. That is, no framing bits are generated
and no channels (DS0s) are defined. The full bandwidth of the T1 is used for
data (in this case, the selected pattern). If D4 is selected, the QuickBERT-T1
will frame the selected pattern in 24 channels and 12 frames (as defined by
®
AT&T
specification 62411). The ESF selection generates a T1 signal in the
24-frame, 24-channel format (per AT&T specification 62411). SLC96 is a
special framing format that can be used when testing digital loop carriers
(conforming to TR-TSY-00008).
Note
Sometimes D4 framing is referred to as SF or super frame.
2-58. Volume Control
If the receiver of the QuickBERT-T1 or QuickCHECK-T1 is in frame sync
(indicated by the green Frame LEDs), a channel may be selected for audible
monitoring. The demodulated audio signal for the selected channel (DS0) is
dropped to an internal speaker. The volume control, located on the right side of
the unit, is used to adjust the audio volume. A headset jack (for use with a
customer-supplied headset) is also provided for noisy environments. See
Appendix A for a description of the headset jack specifications.
2-59. Indicators
Status, alarm, framing, signal presence, and coding information can be
monitored from front-panel LEDs. Detailed descriptions of these front-panel
LEDs are described in the following paragraphs.
2-60. Errors LEDs
The Errors LEDs are labeled BIT ERR, BPV ERR, FRM ERR, CRC ERR, and
FREQDEV. All of these LEDs illuminate solid to indicate errors are present
and flash to indicate error history. Additional information on these errors can
be viewed using the RESULTS keys. Detailed descriptions of each of these
parameters are described earlier in this chapter.
2-61. Data Bits LEDs
The received data for the selected DS0 channel is dropped to the eight Data
Bits LEDs. The Data Bits LEDs are labeled 1 through 8, indicating the data-bit
2-22
Advertisement
Table of Contents
