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Table 4

Approximate delay contributions at 140 MHz to a 700 km baseline.

Effect Delay Timescale


Correlator model error ~75 ns 24 h (periodic)
Station clocks ~20 ns ~20 min
Source position offset (1.5′′) ~ 15 ns


Slowly varying ionosphere ~300 ns ~h
Rapidly varying ionosphere 10 ns ~10 min
Differential ionosphere 5 ns/deg sep.
(source elevation 60 deg)

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