Wiring instructions, Page 3 – Sigtronics SCI-S6 Installation Instructions User Manual

Page 3

Note: If the aircraft already has pilot headset jacks, the location

can be used for intercom with the following changes. The mic
jack must be re-wired as follows:

1. Remove any existing wires from the tip, ring, and barrel connec-

tions.

2. Connect the intercom white/black wire to the ring terminal.

3. Connect one end of a wire to the barrel terminal of the mic jack

and connect the other end to Point “A”.

4. Install insulating washers as necessary if the barrel of the mic

jack is mounted in metal.

For the headphone jack, replace the mono headphone jack with
the stereo headphone jack. Connect the green wire (P2 pin 1) to
the tip connection. Connect the white/green wire (P2 pin 7) to the
ring connection.

WIRING INSTRUCTIONS

Connections should be made as shown in Figure 4 and indicated
in Tables 1 and 2. If longer wire lengths are required, use a good
quality hook-up wire - 22 gauge or larger. Although not necessary,
shielded audio wire can be used if desired. This can simplify the
wiring process.

TABLE 1 - P1/J1 - See Wiring Instructions

WIRE COLOR

FUNCTION

CONNECT TO

White/Black

Pilot Mic Input

Ring Terminal of Pilot Mic Jack

White/Red

Pilot Transmit Switch
Input

Pilot Transmit Switch (PTT) (Switch to
Ground to Transmit)

Blue *1

Radio Headphone Input

Radio Headphone Output

Black *2

Intercom Central
Grounding Point “A”

Aircraft Chassis Ground

White

Radio Transmit Key
Output

Tip Terminal of Aircraft Hand Mic Jack,
or Key Input of Aircraft Radio or Audio
Panel

Brown

Transmit Mic Audio
Output

Ring Terminal of Aircraft Hand Mic
Jack or Mic Input of Aircraft Radio or
Audio Panel

Red *3

12 through 28 VDC
Power Input

Intercom Circuit Breaker

Tan *4

Passenger #1 Mic Input

Ring Terminal of Passenger #1
Intercom Mic Jack

Tan *4

Passenger #2 Mic Input

Ring Terminal of Passenger #2
Intercom Mic Jack

White/Blue

Co-Pilot Transmit Switch
Input

Co-Pilot Transmit Switch (PTT) (Switch
to Ground to Transmit)

White/Orange

Co-Pilot Mic Input

Ring Terminal of Co-Pilot Mic Jack

N/C

None

No Connection

Tan *5

Passenger #3 Mic Input

Ring Terminal of Passenger #3
Intercom Mic Jack

Tan *5

Passenger #4 Mic Input

Ring Terminal of Passenger #4
Intercom Mic Jack

N/C

None

No Connection

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page 3

This manual is related to the following products:

SCI-S4 Installation Instructions