Black Box MT721AE-X21T User Manual
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Order toll-free in the U.S. 24 hours, 7 A.M. Monday to midnight Friday: 877-877-BBOX
FREE technical support, 24 hours a day, 7 days a week: Call 724-746-5500 or fax 724-746-0746
Mail order: Black Box Corporation, 1000 Park Drive, Lawrence, PA 15055-1018
Web site: www.blackbox.com • E-mail: info@blackbox.com
FREE technical support, 24 hours a day, 7 days a week: Call 724-746-5500 or fax 724-746-0746
Mail order: Black Box Corporation, 1000 Park Drive, Lawrence, PA 15055-1018
Web site: www.blackbox.com • E-mail: info@blackbox.com
CUSTOMER
SUPPORT
INFORMATION
MARCH 1995
MT720A-232T
MT721AE-X21T
MT720A-35T
MT722A-232T
MT720AE-X21T
MT722A-35T
MT721A-232T
MT722AE-X21T
MT721A-35T
Fradswitch-8A (232)
Fradswitch-8A (V.35)
Fradswitch-8A (X21)
Fradswitch-16A (232)
Fradswitch-16A (V.35)
Fradswitch-16A (X21)
Fradswitch-24A (232)
Fradswitch-24A (V.35)
Fradswitch-24A (X21)
FRADSWITCH-8A
PWR
1
MAIN
2
3
1
SYNC
2
3
1
CHAN
NELS
2
3
4
5
6
7
8
ERR
OVF
TEST
RESE
T
1
2
3
4
5
6
7
8