EFJohnson 3000 SERIES - Manual (Page 110)

SYSTEM NETWORK MODULE (SNM)
13-4
Main Transmit
1. Determine the maximum level to be received by the
ancillary equipment to be transmitted.
2. Set S5 for Test 1 (open section 1, close sections 2, 3
and 4).
3. Reset the module, Press S2 and release.
4. Adjust R44 for -12 dB from the maximum level in
Step 1 at J12.
5. Set S5 for Test 8 (open section 4, close 1, 2 and 3).
6. Reset the module, Press S2 and release.
7. Adjust R86 to be -12 dBm ± 0.5 dB at TP4.
8. Verify the level at J12 to be -21 dB ± 1 dB from the
maximum level from Step 1.
9. Select for normal operation (S5 all sections closed).
10.Reset the module, Press S2 and release.
Example: Microwave has -16 dBm max input, set
J12 for -28 dBm.
Main Receive
1. Determine the maximum transmit level that is sent
by the ancillary equipment to the interface module.
2. Set S5 for Test 1 (open section 1, close sections 2, 3
and 4).
3. Reset the module, Press S2 and release.
4. Insert the maximum level determined in Step 1
using a 600 ohm audio oscillator into EQU port of
J1. Otherwise, set the ancillary equipment to send
the alignment tone to the interface module.
5. Adjust R41 to be -6 dBm at J11.
6. Close section 2 of S1.
7. Adjust R102 to be 0 dBm at TP8.
8. Set S5 for normal operation (all sections closed).
9. Reset the module, Press S2 and release.
Example: Microwave has +7 dBm maximum
output, set J11 for -5 dBm.
Secondary Transmit and Receive
Not used since the secondary line is not used.
Figure 13-3 SNM CABLE LAYOUT
NOTE: This cabling is used within a single Switch or between Switches to allow Unique ID calls to occur.
EA
EB
MA
MB
RXA+
RXA-
TXA+
TXA-
EA
EB
MA
MB
RXA+
RXA-
TXA+
TXA-
SNM SNM