Table 7-3. Troubleshooting Intercommunication Switchboard SB-2601/G

TM 32-5895-227-14&P

indicates the proper jack location for stations 1 through

7-8

TROUBLESHOOTING SB -2601/G.

29 and the switch light indicator on the RICS.

a. General. Perform the procedures indicated

(2) Wiring diagram for SB-2601/G is shown

below for sectionalizing, localizing, and isolating trouble

in FO-6. This diagram outlines a complete electrical

to a particular circuit in the Intercommunication

means of performing maintenance on this unit. It

Switchboard SB-2601/G.

consists of connectors, switches, relays, and associated

b. Diagrams.

wiring.

(1) The location diagram for SB-2601/G is

c. Troubleshooting Chart. Table 7-3 identifies

shown in figure

7-4.

There are 29 external

the trouble symptoms, the probable troubles, and the

intercommunication positions in AN/MSQ-71 which can

corrective actions to be taken

be transferred individually to any one of 10 channels on

RICS. Location of the transfer switches and relays are

shown in figure 7-4. Also, the rear view of SB-2601/G

Table 7-3. Troubleshooting Intercommunication Switchboard SB-2601/G

Item

Trouble symptom

Probable trouble

Corrective action

number

No power indication.

Burnt-out fuse (located at rear of

Remove and replace burnt-out fuse.

SB-2602/G)

Faulty electrical connections or wiring

Check power cable connections at

between SB-2601/G and SB-2602/G

connector J1 on SB-2601/G and J1 on

SB--2602/G. Check continuity and/or

voltage to SB-2601/G.

Defective power supply PS2 (located in

Refer to FO-6. Check 115 Vac input to

SB-2602/G)

power supply PS2 at terminal board

TB1.

Check for 20 Vdc at output. If no output,

power supply is defective. Remove and

replace faulty PS2 components as

required.

Inability to transfer

Defective station transfer switches S1

Refer to FO-6. Check for electrical

individual channels.

through S10

continuity and proper operation of station

transfer switches SI through S10.

Defective SB-2600/G

Troubleshoot suspected SB-2600/G as

Inability to transfer an

outlined in table 7-5.

individual station on

all channels.

Faulty electrical connections

Check cable connections at J5 of SB-

2600/G and J1 through J18 at OA-

7735/G to be sure they are secure.

Inability to transfer

Defective relays KI through K18 (located

Refer to FO-6 for presence of 20 Vdc at

an individual station

in OA-7735/G console)

relay coils K1 through K18. If 20 Vdc is

on a specific channel.

present and relay coil is not energized,

relay is defective. Remove and replace

relay.

7-9