Masterclock CLKTCD12, Руководство пользователя

Страница: 28 / 39

CLKTCD12 User Manual 25
© Masterclock
®
, Inc 2006-2007.
Rev 1.2.0 May ‘07 http://www.masterclock.com
Problem: The CLKTCD12 displayed time [local] is off a small amount when compared
to a reference digital/analog time display, or the Windows USB Configuration Utility
[screen display].
Possible reasons/solutions:
1. Perception/recognition response time. The average human ability to visually perceive
and recognize time [synchronization] and/or instantaneous change between two
visually separated stimuli is limited due to the movement of the eyes and the delayed
response to process the data. To reduce this effect:
•
Place the digital/or another analog display adjacent to the clock you are trying
to verify the time on.
•
View the clocks from a position [straight on – dead center] that will avoid
parallax and minimize eye movements.
•
Ensure that your clocks [reference unit and clock you are testing] are both
locked to an accurate source [preferably the same time code source].
•
Ensure that both units have the same offset settings for time zone and/or DST.
2. The Windows USB configuration utility’s screen display is a GUI (graphical user
interface) that is not being run at the highest priority level for the system. There will
likely be a delay [depending upon system resources and the running tasks it could be
as much as a few seconds] in processing the data and updating the screen ; therefore it
should not be considered to be an accurate reference.
3. Ensure that you are not using Drop-Frame SMPTE time code. Drop-Frame time code
is not supported. Accurate time cannot be guaranteed with drop-frame time code.
4. The clock hands have been incorrectly calibrated with either the calibration buttons or
the USB configuration utility. See the calibration procedure for details on how to
recalibrate the hands.
Problem: The CLKTCD12 did not properly negotiate the daylight time to standard time
(or vice-versa) transition.
Problem: The date shown in the status window of the configuration utility is always
01/01/2000.
Possible reasons/solutions:
1. Your time code source is not providing date/year information. The daylight savings
time adjustment feature will not work unless valid date information is provided.
Verify that your time code source has either date encoding to the Leitch standard for
SMPTE time code , or year/date encoding to the IEEE 1344 specification for IRIG-
B/B1 time code. Masterclock provides equipment to these standards.
2. The TC control switches S2-1 and S2-2 have both been set to OFF; and/or the time
code date encoding has been disabled in the configuration utility.
3. Your time code source already provides the daylight savings time adjustment. The
daylight savings time adjustment feature in the CLKTCD12 should be disabled.
4. You have disabled the DST setting or the incorrect DST setting was enabled. The
CLKTCD12 has switches for enabling various modes of DST, or disabling the DST
option. In addition, to the switches, the USB configuration utility may be used to set
the DST settings as well as all configuration settings of the clock. If the USB