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When the number you’d like to use is showing you can hit the RESET button to exit
the Configuration Mode. Or, to continue with the next configuration setting, press the
MODE button.
Time Mode display format
You can configure MicroSet to display the results of its Time Mode measurements in
Seconds Per Beat or in Beats Per Hour. When you enter this configuration setting the
display will show either
Units: Secs
or
Units: BPH
To have MicroSet display Time Mode measurements in Seconds Per Beat, press the
PLUS key and the display will show “
Units: Secs
”. To have MicroSet display time
measurements in Beats Per Hour press the MINUS key and the display will show
“
Units: BPH
”.
MicroSet can also display rate as seconds of error per day. This setting is made with
the Time Mode Options.
If you’re through with configuration after this setting, hit the RESET button. To continue
with the next configuration setting, press the MODE button.
Oscillator calibration
The final setting in the Configuration Mode allows you to enter a “trim” value that is
used to correct for inherent errors in the quartz crystal time base. This unique feature
allows us to recalibrate your MicroSet timer with software if the accuracy of the quartz
crystal changes over time. Don’t change this setting unless you know what you’re doing
and have a good reason to change it. You may want to record the factory setting for
this value inside the back cover of this instruction manual. If anything goes wrong and
the trim value gets changed, you can re-enter the original value. You (or we) can make
adjustments to this setting as the unit ages, and it allows us to recalibrate MicroSet
without making any changes to the hardware.
When you enter the Trim Mode, the display will show something like the following:
Trim: 0
The range of values is +99 to -99. To increase the trim value, press the PLUS button. To
decrease the trim value, press the MINUS button. When the value you want is displayed,
you must press the BEGIN button if you want MicroSet to memorize it. When you do, the
LCD screen will show “OK!” and the trim value will be stored in permanent memory for
future use. This extra key press helps to insure that the trim value will not be changed
accidentally.
The units of Trim are “parts per million”. If the Trim value is “+1”, it means the crystal
oscillator is accurate to one part per million, and the remaining one part per million error
is corrected with the software Trim value. The final error of the timer is always zero parts
per million when it’s at the same temperature it was when it was calibrated.
Experience has shown that MicroSet does not lose much accuracy over time. We have
gotten several units back for upgrades after more than a year, and the trim value has
always been within two or three parts per million of correct. Often the timebase has not
drifted at all after a year. A change of 1.65 parts per million is a change of one second
per week. Your timer is not likely to be off by more than this in a year’s time.
