Digital Control F2 DCI DigiGuide User Manual page 4

An A on the screen can indicate signal Attenuation due to the presence of
excessive interference, which can make depth readings inaccurate.
Attenuation is normal in shallow depths less than 2.4 m. If the signal strength
is also flashing; this indicates extreme interference. Depth and locate points
may be compromised and the locator will not calibrate.
Interference is classified as either active (generating electro-magnetic signals)
or passive (material that can conduct or block electro-magnetic signals).
Sources of interference may include:
Active
Traffic signal loops
Buried dog fences
Cathodic protection
Radio communications
Security systems
Microwave towers
Power, phone, fiber-trace and cable TV lines
Passive
Metal pipes
Rebar
Trench plates
Chain-link fences
Vehicles
Saltwater/salt domes
Conductive earth, such as iron ore
DIGITAL CONTROL, INC
DIGITRAK FALCON F2 TOP TOGGLE USER MANUAL
DCI DigiGuide 05.18.2024
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