Güralp DM24 MkIII, Operator'S Manual

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Güralp DM24 Mk
Ⅲ
Inside the DM24
Here, a 64 Mb Flash memory store contains 65,520 data blocks, of which none have
already been downloaded. This leaves 16 blocks of free space, since each block is
exactly 1Kb long, and (65,520 + 16) × 1 Kb = 65,536 Kb = 64 Mb.
Latest data [392] PLPGG SBHYX2 2006 1 18 14:55:57
Oldest data [400] PLPGG SBHYN4 2005 11 30 06:47:38
These two lines show the date and time of the oldest and newest data in the buffer,
together with the
System ID (
PLPGG
) and the Stream ID s (
SBHYX2
and
SBHYN4
) of the
corresponding data stream.
7.1.1.2 Triggered events
# 15 Filed @ 64,167 PLPGG SBHYZG 2006 1 5 10:31:30 Last
Event
This line gives the date and time of the last trigger, together with its System ID and
Stream ID
as above. Also given is the event sequence number (15, here) as used by
the
EVENTSLIST
command, and the position in the buffer where data from the event
begin.
If a trigger has occurred, but no data were output (
e.g.
because the digitiser was in
DIRECT
transmission mode), the digitiser will report
# 22 2006 1 18 14:48:36 No File Last Event
7.1.1.3 GPS
The next line describes the current status of the GPS system. When the digitiser is
first powered up, the message will be something like
2005 8 10 12:35:00 GPS control OFF Auto 3-D [-5 Not sync'd]
The message GPS control OFF denotes that the clock is not yet being controlled by
the GPS. Owing to noise purposely injected into the GPS timing stream, the GPS time
cannot be directly used to synchronize the clock. Instead, the digitiser maintains a
rolling average of time measurements, and uses this to apply corrections to the clock
so that it remains accurate over a long period.
The
Auto 3-D
message denotes that the signal is strong enough to obtain a full 3-
dimensional GPS fix. If the signal is weak, or there are too few satellites visible to
the receiver, you may see
Auto 2-D
here. If the signal is too weak to obtain a fix,
No
FIX
will be displayed.
After a short time, the message will change to
2005 8 10 12:36:00 GPS Control settling Auto 3-D [-5 Not sync'd]
Eventually, the GPS control system will be able to synchronize the internal clock,
and the message will change to
2005 8 10 12:38:01 GPS Control settling Auto 3-D [-4]
2005 8 10 12:41:01 326 MicroSeconds Slow Freq error -7 e-9 Auto
3-D [-4]
MAN-D24-0004 96 Issue U - December, 2021