Captains,
We hope the following info will help those who are not familiar with the original C-130 autopilot ops and its vintage avionics overall:

1. Attitude Hold. Standard maneuvers may be executed with the pitch and turn knobs.
PILOT SWITCH: ON
RADIO BEAM COUPLER SWITCH: GYRO PILOT
FLT DIR Switch: NORMAL
MODE SEL Switch: any
ALTITUDE CONTROL SWITCH: OFF

2. Altitude Hold
PILOT SWITCH: ON
RADIO BEAM COUPLER SWITCH: any (In APPROACH position, when the glideslope is intercepted, the altitude control switch will go to the OFF position)
FLT DIR Switch: any
MODE SEL Switch: any
ALTITUDE CONTROL SWITCH: ON

3. Heading mode
PILOT SWITCH: ON
RADIO BEAM COUPLER SWITCH: GYRO PILOT
FLT DIR Switch: MANUAL
MODE SEL Switch: HDG
ALTITUDE CONTROL SWITCH: any
Heading set knob (on HSI) can be used to select a heading to fly.

4. Automatic flight on an VOR course
PILOT SWITCH: ON
RADIO BEAM COUPLER SWITCH:  RANGE-LOC
FLT DIR Switch: NORMAL
MODE SEL Switch: VOR/ILS 1 or VOR/ILS 2
ALTITUDE CONTROL SWITCH: any
VOR receiver: set to the desired frequency
Pilot's HSI: set the desired course with the Course Set Knob

5. Automatic Approach
PILOT SWITCH: ON
RADIO BEAM COUPLER SWITCH: APPROACH (APP)
FLT DIR Switch: NORMAL
MODE SEL Switch: VOR/ILS 1 or VOR/ILS 2
ALTITUDE CONTROL SWITCH: any (when the glideslope is intercepted, the altitude control switch will go to the OFF position)
ILS receiver: set to the desired frequency
Pilot's HSI: set the inbound localizer course with the Course Set Knob

6. Following GPS flight plan
PILOT SWITCH: ON
RADIO BEAM COUPLER SWITCH:  RANGE-LOC
FLT DIR Switch: NORMAL
MODE SEL Switch: NAV
ALTITUDE CONTROL SWITCH: any

7. Flying inbound on the back course of the localizer or outbound on the localizer beam.
PILOT SWITCH: ON
RADIO BEAM COUPLER SWITCH: BLUE LEFT-LOC
FLT DIR Switch: NORMAL
MODE SEL Switch: VOR/ILS 1 or VOR/ILS 2
ALTITUDE CONTROL SWITCH: any
ILS receiver: set to the desired frequency
Pilot's HSI: set the localizer course with the Course Set Knob