Specifications

Chapter 4: Using SYNC I/O 39
To resolve SYNC I/O to Linear Time Code from
Pro Tools:
■ In the Sync Setup section of the Session Setup
window, choose an LTC setting from the hierar-
chical Clock Reference pop-up menu. Choices
include:
LTC 0 (fastest) Allows the quickest resolving to
incoming LTC, but with greater jitter. This is the
default setting, and should be used when fast
lock ups are critical.
LTC 1 Provides an intermediate fast setting.
LTC 2 (average) Offers a compromise of lock up
time and jitter quality.
LTC 3 Provides an intermediate slow setting.
LTC 4 (smoothest) Offers the lowest jitter from
LTC resolve, but can take six to ten seconds to
achieve full resolve. This setting is most appro-
priate when loading critical audio from an ana-
log master, where reducing or eliminating jitter
is more important than lock speed. Be sure to al-
low adequate pre-roll before punching in.
To resolve SYNC I/O to Linear Time Code from the
front panel:
■ Press the Clock Reference switch to select LTC.
To resolve SYNC I/O to Linear Time Code using
SYNC I/O Setup software utility (Windows only):
■ Select Linear Time Code (LTC) from the
SYNC I/O Setup Clock Ref pop-up menu.
Additional LTC Information
LTC can provide positional and clock reference.
LTC can be recorded onto and played back from
an analog track, or a VTR audio, address or cue
track.
Pilot Tone
SYNC I/O can resolve to an external Pilot Tone
signal for clock reference, for synchronizing to
(or transferring audio from) certain types of
open-reel audio tape recorders. Pilot Tone is ba-
sically a 60 Hz (NTSC) or 50 Hz (PAL) sine wave
tone. Pilot Tone is used on location film shoots
to establish a common sync reference between a
film or video camera with a portable 1/4-inch
analog ATR. Pilot Tone contains no positional
information; it provides only clock reference.
SYNC I/O decides whether to use 60 Hz or 50 Hz
as the pilot tone reference frequency according
to the setting of the Video Format. When set to
PAL, the pilot tone frequency is assumed to be
50 Hz. When set to NTSC, 60 Hz is assumed.
Connect the Pilot Tone reference source to the
SYNC I/O Bi-Phase/Tach/GPI/Pilot port.
To resolve SYNC I/O to Pilot Tone:
From Pro Tools:
■ In the SYNC Setup section of the Session
Setup window, select Pilot Tone from the Clock
Reference pop-up menu.
From the front panel:
■ Press the Clock Reference switch to select
PILOT.
SYNC I/O provides adjustable LTC servo
gain. See “Servo Gain” on page 60.
For further information on LTC signals, see
“LTC Signals” on page 68.