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6 - Audio Left / Mono In
7 - Blue
8 - Control Voltage
9 - Green Gnd
10 - Comms Data 2
11 - Green
12 - Comms Data 1
13 - Red Gnd
14 - Comms Data Gnd
15 - Red
16 - Fast Blanking
17 - Video Gnd
18 - Fast Blanking Gnd
19 - Composite Video In
20 - Composite Video Out
21 – Shield Gnd
Some cheaper SCART cables use unshielded wires, which is just about acceptable for short cable lengths. For
longer lengths, shielded co-ax cable become essential.
Scart Signals:
Audio signals
0.5V RMS, <1K output impedance, >10K input impedance.
Red, Green, Blue
0.7Vpp ±2dB, 75R input and output impedance. Note that the Red connection (pin 20) can alternatively carry the
S-VHS Chrominance signal, which is 0.3V.
Composite Video / CSync
1Vpp including sync, ±2dB, 75R input and output impedance.Bandwidth = 25Hz to 4.8MHz for normal TV
Video de-emphasis to CCIR 405.1 (625-line TV)
Fast Blanking
75R input and output impedance. This control voltage allows devices to over-ride the composite video input with
RGB inputs, for example when inserting closed caption text. It is called fast because this can be done at the same
speeds as other video signals, which is why it requires the same 75R impedances.
0 to 0.4 V: TV is driven by the composite video input signal (pin 19).Left unconnected, it is pulled to 0V by its
75R termination.
1V to 3V: the TV is driven by the signals Red, Green, Blue and composite sync. The latter is sent to the TV on
pin 19. This signal is useful when using a TV to display the RGB output of devices such as home computers with
TV-compatible frame rates. Tying the signal to 5V via 100R forms a potential divider with the 75R termination,
holding the signal at around 2V. Alternatively, if a TTL level (0 to 5V) negative sync pulse is available, this will
be high during the display periods, so this can drive the blanking signal via a suitable resistor.
Control Voltage
0 to 2V = TV, Normal.
5 to 8V = TV wide screen
9.5 to 12V = AV mode
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