Sercel Inc 0104A ユーザーズマニュアル
14
Maintenance:
Calibration
The 1200-bps mode needs an oscillator of LRC-508 radio with a 1-ppm accuracy or better. To guarantee such
accuracy along the lifetime of the product, a calibration of oscillator frequency is necessary one time every year.
To do that, deploy LRC-508 in an open-sky environment and at about +25°C +/- 5°C. Launch an oscillator calibration
test, internal GPS Pulse-Per-Second is the reference during this test.
Other setups are allowed to do such calibration:
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Indoor calibration and use a GNSS repeater
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Connect LRC to a IEEE1588 network, with a Master Clock
IMPORTANT
Prior to connecting any plug, make sure there is no water inside connectors.
Electrostatic discharge:
Use the following guidelines to provide a static-free repair station that will preclude any ESD-related
damage to electronic circuits:
• All spare parts (circuit boards and ESD sensitive devices) should be stored and transported in static-
shielding bags.
• Unless the repair station rests on a conductive floor, chairs or stools should rest on a grounded, rigid-
type, static-dissipative floor mat.
• Use a static-dissipative table mat.
• Wear a static-control wrist strap or foot grounder.
• Provide common-point grounding for all conductive items (including personnel and soldering iron tip).
• To control the discharge rate and protect workers from electric shocks, both the table mat and wrist
strap should be grounded through a 1-MΩ resistor. The mat should be connected to the same earth
ground point as the wrist strap.
• Wear static-dissipative garments.