Garmin GPS II Owner's Manual page 73

Track Method
The stored track method determines how often positions are stored in the track
log. The default setting is automatic, which will store a track based on resolution.
This setting gives you the most efficient use of track memory and provides the most
accurate TracBack route.
To change the method to record points based on a specific time interval:
1. Highlight the 'method' field, and press ENTER.
2. Select 'TIME INTERVAL' (Fig. 67a), and press ENTER twice (Fig. 67b).
3. Enter a value in hours, minutes, and seconds, and press ENTER.
Track Log Display
The track log option sets the number of points the unit will attempt to display
on the map page. The default setting of 250 points provides good resolution with
minimal screen clutter. The maximum setting is 768 points. Once you've reached the
maximum number of track points, the older points will be lost as new points are
added. Note that adjusting the track points displayed will not affect whether the
receiver records a track log or the ability to create a TracBack route.
REFERENCE
Fig. 67a
Fig. 67b
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