OPERATION
Section 2
30
TIMEWISE 798A
Details,
Details,
Details…
You may need to read the following information a few times before it becomes meaningful:
The 798A totals distance separately for each “speed section”. (Each segment of the route
driven at an assigned rally speed is referred to as a “speed section”.) As mentioned, the 798A
doesn’t distinguish between distance accumulated via transducer pulses and distance entered
via the
Ad j u s t O RM
function. To be precise, distance entered via the
A d j u s t O RM
function
is considered part of the “active” speed section (i.e., the current speed section).
As will be explained in detail later, the active speed section distance is used when employing
the
Retro-CAST
™ function. Should a
Retro-CAST
be executed, all
A d j u s t O RM
changes,
as well as the actual driven distance, will affect the re-computation of the calculated time.
Therefore, when you don’t want odometer adjustments to be part of the active speed section
(and used by the
Retro-CAST
function, should that feature be employed), do not use the
A d j u s t O RM
function. Instead, use the
Odo & Time
function as explained in detail later.
Whew! What the…? Don’t worry. This information is restated later in a slightly different
manner. It will become clearer when you read about the
Retro-CAST
and
Odo & Time
functions. And if you’re a driver, rather than a navigator, you may not care anyhow.
Adjusting
the Auxiliary
Odometer
(Option 5)
As of version 6.000 firmware, the 798A is always outfitted with an adjustable auxiliary
odometer. To adjust the auxiliary odometer, make it visible in the Auxiliary display, turn the
rotary switch to
Odometer
, select
SHIFT
, and use the “+ / –” toggles. There is no italicized
label below the word
Odometer
that indicates the auxiliary odometer adjustment function.
Note
: You can adjust the auxiliary odometer only when the auxiliary odometer is vis i ble .
The 798A disables adjustments to the main odometer for about one second following an
adjustment to the auxiliary odometer. This prevents changes to the main odometer should
you accidentally release the
SHIFT
switch while making an auxiliary odometer adjustment.
Auxiliary odometer adjustments do not alter either the main odometer or the calculated time.
Truncating the
Main
Odometer
As mentioned, the 798A measures distance to a resolution of 0.000
00001
mile. The five
least significant digits (shown in bold type) are internal to the instrument, and cannot be
seen. These internal digits are generally not of concern to the rallyist since official distances
are most often given to a resolution of 0.01 or .001 mile.
Still, there are occasions when the internal digits of the odometer can be important. For
example, when resetting the odometer at the beginning of the rally, the internal digits must
also be cleared to all zeros. Although you can use the “+ / –” switches to adjust the main
odometer to show 0.000 miles in the
O D O M E T E R
display, the values of the internal digits
would be unknown. You must zero the internal digits to measure from exactly zero miles.
To clear the internal digits of the main odometer, momentarily select
T RU N CA T E
on the
CAST–TRUNCATE
toggle switch.
†
When
T RU N CA T E
is actuated, the internal digits of the
main odometer, as well as the thousandths of miles digit in the display, are reset to zero. The
main odometer is, thusly, truncated to an exact hundredth of a mile (xxx.xx000000).
†
If desired, you can enable a short delay before a truncate action is recognized. To implement the delay, turn on the 798A while holding
down the
SHIFT
and
T R U N C A T E
switches. With the delay enabled, you must depress the
T R U N C A T E
switch for 1 second to execute
the truncate. The beeper will signal when the delayed truncate occurs. (Repeat the described turn-on procedure to revert to the “no
delay” factory setup.)
