Sound Devices 744T, User Manual

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744T User Guide and Technical Information
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v. 2.67 Features and specifications are subject to change. Visit www.sounddevices.com for the latest documentation.
The hard drive is mounted to the bottom-side of the recorder’s chassis and is screwdriver accessible.
The drive is “suspended” in the unit with a shock absorbing foam and is attached to the main circuit
board via a “flex board”. Since the unit’s high-density circuitry and tight construction require specific
electronics knowledge, Sound Devices strongly recommends drive replacement be performed by a
qualified technician using proper ESD precautions. Drive replacement done by a qualified technician
has no warranty implications.
744T with bottom panel
removed showing hard
drive mounting location
The internal hard drive is not intended as a swappable exchange medium. The header connector is not
rated for repeated removal and insertion. Only qualified service technician using proper ESD precautions
should perform drive replacement.
Drive Failure
Hard disk drives are mechanical devices and are susceptible to damage from physical shock. One
type of physical shock, called operating shock , occurs when the disk is in operation. During opera-
tion, the drive head is typically over the drive platters reading and writing data. When a physical
shock to the drive occurs during operation, the head and the platters can come into contact causing
both components to be damaged. The second type of shock, called non-operating shock , occurs
when the head is in the unloaded position, or not positioned over the platters. When a physical
shock occurs in the non-operating state, the head can contact the ramp it is positioned over and dam-
age the ability of the head to read and write data to the hard disk drive. All devices with hard drives
are subject to damage from operating and non-operating shock.
The mechanical construction of the 744T is designed to minimize the transmission of shock to the
hard drive. The drive is isolated from the chassis using special shock-reducing closed-cell foam. This
material increases the amount of shock the hard drive can withstand. Additional protection can be
achieved by operating the unit in a carry case.
If the recorder is used in applications subject to extreme motion, Sound Devices recommends recording to
CompactFlash only. The hard drive will park its write heads to reduce the chance of failure.
With all electrical devices, the higher the ambient temperature the shorter the device’s operational
life. Therefore, take care to observe the specified temperature rating.
There is also a risk from sudden temperature changes, which can create condensation inside the
drive. This condensation can lead to the drive’s read/write heads adhering to the disk surfaces