IBM 5280 Manual page 207

X
9
COMMUNICATION MAP
38LS XMIT/RECV CHECK
PAGE 11 OF 20
052
- Check for the correct dB level
going into the the World Trade
line plate.
Connect the dB meter between
TPl, 'Telephone Line 1', (MIM
827) (which is a direct line to
TBl-9) and TB2, 'Telephone Line
2' (MIM 827) (which is a direct
line to TBl-8).
Is the dB level correct?
Y N
A
A
053
- Check for the correct dB level
at the J140 connector on the
external cable (MIM 869, probe
point H).
Connect the dB meter between
J140-l3 '- Telephone Line 1',
and J140-14 'Telephone Line
2'.
Is the dB level correct?
Y N
054
Defective external cable.
055
- Defective internal cable that
connects the World Trade line
plate to Jl40.
A
A
MAP 3011-11
056
Note: If you
following dB
dB meter or
cannot verify the
measurements (bad
such), seeing that
Carrier Det' is
active
33LS is verifies that the
receiving the signal.
Probe A-D7B12, '- Carrier
(MIM 869, probe point B).
Det'
Up light: O-ff
Down light: On
Are the lights correct?
Y N
057
Power off.
Disconnect the internal cable
from the communications MPU
card at connector A-E5-J01.
At the POl connector ON THE
INTERNAL CABLE check
continuity between POI-07,
'Data Tip', (MIM 8'9, probe
point E), and the line plate
connector A08 (MIM 869, probe
point F).
connector ON THE At the POI
INTERNAL CABLE check
POl-23, continuity between
'Data Ring',(MIM 869,
point E), and the line
connector B08 (MIM 869,
point F).
probe
plate
probe
Is continuity good?
Y N
1 1
2 2
A A
B C
058
Defective cable between the
Communications MPU card and
the World Trade line plate.
EC840874 PEC839787
MAP 3011-11