Black Box ME444A-530-R3, ME444AE-R3, ME445C-X.21, ME445C-35, ME444A-R3, ME445C-530 Bert using loops

256-KBPS LINE DRIVER (V.35, RS-530, OR X.21)

PATT

PRESSED

PATTERN XMT

GENERATOR

PATTERN

TESTER RCV

ERROR

ASM-20

Figure 6-1. BERT using loops.

PATT	DEPRESSED
	(DISCONNECTS
DEPRESSED	EXTERNAL DTE)
		RCV
PATTERN	PATTERN
GENERATOR	TESTER
	ERROR	DTE
PATTERN	PATTERN	XMT
TESTER	GENERATOR

ERROR

Figure 6-2. Two line drivers doing end-to-end BERT.

40