EFJohnson 3000 SERIES - Manual (Page 150)

LOGGING ENCODER MODULE (LEM)
17-2
17.2 LEM SETUP PROCEDURE
17.2.1 LEM SWITCH SETTINGS
See Figure 17-2 for Alignment Points Diagram.
17.2.2 LEM JUMPER PLACEMENT
17.2.3 LEM BACKPLANE EXTERNAL
CONTACTS
See the Backplane Section 23 for pinouts on the
shelf backplane and wire harness pinouts.
The main transmit audio of the LEM is the only
external connection that is required. This connects to
the logging recorder.
17.3 LEM ALIGNMENT SPECIFICATIONS
17.3.1 PRE-ALIGNMENT
The LEM is pre-aligned with the Basic Board
Module alignment procedures. Refer to Section 7.3.
17.3.2 LEM ALIGNMENT PROCEDURE
The main transmit audio of the LEM is the only
connection to the logging recorder. Good alignment
practice should be followed and the module should be
adjusted accordingly.
Connections to the LEM are:
1. Direct Connection
2. Leased Lines
3. Microwave Link
4. T1 Channel Bank Interfaces
This ancillary equipment requires certain input
and output levels for proper operation. The module
should be adjusted accordingly.
Table 17-1 LEM SWITCH SETTINGS
Switch Open Sections Close Sections
S1
S3
S4
S5 1
1
1
-
2
2
2
-
-
3
3
-
4
4
4
-
-
-
-
1
-
-
-
2
3
-
-
3
-
-
-
4
Table 17-2 LEM JUMPER PLACEMENT
JU Pin Description
J24 1 to 2*
2 to 3 Selects 27512 EPROM operation
Selects 27256 EPROM operation
J27 1 to 2
2 to 3* Not used
Normal operation
P33 1 to 2
3 to 4
5 and 6 open
open
open
J36 1 only
1 to 2
2 to 3 Not used
-48V E-lead operation
-15V E-lead operation
J14
J15
J21
J22 Jumper pin 1 to 2 for high impedance ground path
for split 600 ohm inputs and outputs. Leave open
if no ground path desired.
* Indicates normal operation.
Table 17-3 LEM EXTERNAL CONNECTIONS
Backplane
P34 to P45 Description
Wire Harness
J1,3,5,7
pin 27
pin 28
pin 29
pin 30
pin 31
pin 32 Sec Rx +
Sec Rx -
EA lead
EB lead
Pri Rx Audio+
Pri Rx Audio- pin 1
pin 2
pin 3
pin 4
pin 5
pin 6 RxS+
RxS-
EA
EB
RxA+
RxA-
J2,4,6,8
pin 59
pin 60
pin 61
pin 62
pin 63
pin 64 Sec Tx +
Sec Tx -
MA lead
MB lead
Pri Tx Audio+
Pri Tx Audio- TxS+
TxS-
MA
MB
TxA+
TxA- pin 1
pin 2
pin 3
pin 4
pin 5
pin 6