Loss of the SELCAL Code by the VHF 3 System

TASK 23-51-00-810-827-A
Loss of the SELCAL Code by the VHF 3 System

1. Possible Causes

2. Job Set-up Information
A. Referenced Information

REFERENCE	DESIGNATION
TSM TASK 23-51-00-810-828-A	Loss of the SELCAL Code
ASM 231201
AMM 23-12-33-000-001	Removal of the VHF Transceiver
AMM 23-12-33-400-001	Installation of the VHF Transceiver
AMM 23-51-00-710-002	Operational Test of the SELCAL System
AMM 23-51-34-000-001	Removal of the Audio Management Unit (AMU) (1RN)
AMM 23-51-34-400-001	Installation of the Audio Management Unit (AMU) (1RN)

3. Fault Confirmation
Subtask 23-51-00-710-058-A

A. Test
(1) Do the operational test of the SELCAL system AMM 23-51-00-710-002.

NOTE: Do this test for each HF (if installed) and VHF system.

4. Fault Isolation
Subtask 23-51-00-810-076-A

A. If the ground station cannot make a SELCAL call:
(1) During the operational test of each HF (if installed) and VHF system:

(2) During the operational test of the VHF 3 system only:

(a) If the fault continues:

1 If the fault continues:

Do a check and repair the wiring of the SELCAL OUTPUT signal from the XCVR-VHF, 3 [1RC3] pins AB/13A, 13B to the AMU [1RN] pins AA/3H, 3J ASM 231201.

Subtask 23-51-00-710-059-A

B. Do the test given in Para. 3.

[Rev.8 from Aug 2018] 2026.04.04 04:25:45 UTC