IBM 5280 Manual page 209

A
F
1
2
COMMUNICATION MAP
38LS XMIT/RECV CHECK
PAGE 13
OF 20
067
See 38LS 5witch setting chart in
t-lIM
S13, S15, or 817 to
determine which switches should
attenuation, the 3SLS card
should have been set for 00 dB).
Note: A quick way to identify a
communications MPU card which
has programmable attenuation is
as -follows:
If there are 4 transmit level
attenuators on the lower left
quadrant of the communications
MPU card, the card has
programmable attenuation (MIM
811).
Are all switches on the 3SLS line
adapter card set correctly?
Y N
068
- Set correctly and retry the
test.
069
- Connc:ct
A-D7D05
the dB meter between
lData Tip (DT)' (MIM
867, probe point C), and A-D7D03
'Gnd'. The DB level should be
equal to the LEVEL SET IN THE
38LS lINE ADAPTER
CARD
5WITCHES(MIM
812).
Is the dB level correct?
Y N
1
5
A A
G H
A
H
MAP 3011-13
070
- Power o-f-f.
- Remove the 38LS card.
- Check continuity between A-DSD09
'+Coupler Cut Through (CCT)',
<1'111'1
867, probe poi nt C), and
the Brown leud AT THE COUPLER.
Is continuity good?
Y N
071
- Disconnect the internal cable
from the communications MPU
card at connector A-E5 J01.
- At the POI connector ON THE
INTERNAL CABLE check
continuity between POI-06
'+Coupler Cut Through (CCT)',
(MIM 867, probe point E), and
the Brown lead AT THE COUPLER.
Is continuity good?
Y N
1 1
4 4
A A
J
K
072
- Disconnect
cable from
the external
the mClchine at
connector Jl40.
- At the P140 connector ON THE
EXTERNAL CABLE check
continuity between P140-06
'+Coupler Cut Through
(CCT)', (MIM 867, probe
point F), Clnd the Brown lead
AT THE COUPLER.
Is
continuity good?
Y N
073
Defective external cable.
074
- Defective internal cable.
ECS40874 PEC839737
MAP
3011-13