HP HP-97 - Page 50

Assembly-Level Maintenance
HP-97
Table 3-8. Assembly Level Troubleshooting Procedure
Use this procedure to isolate a malfunction to a replaceable assembly.
STEP
ACTION
. Unplug the AC Adapter/Recharger
from the calculator.
. Measure the AC voltage at the
power outlet, VIN.
. Measure the AC voltage at the out-
put of the Adapter/Recharger,
VOUT.
. Calculate VMIN and VMAX as
follows:
For VIN=230 Vac approx.
VMIN=VIN/21.10
VMAX=VIN/15.65
For VIN=115 VAC approx.
VMIN=VIN/10.55
VMAX=VIN/7.82
If VOUT is between VMIN and
VMAX, go to step 2.
If VOUT is outside VMIN and
VMAX, replace the AC Adapter/
Recharger. Then go to step 2.
2.
. Connect an 11 ohm, 5%, 5W load If VOUT is between 6.2 and
resistor across output of the 7.4 Vac, and the display is
AC Adapter/Recharger. blank, go to step 3.
. Measure VOUT across the load
resistor. If VOUT is less than 6.2
or more than 7.4V replace
the Adapter/Recharger. If the
display is blank, go to
step 3.
3.
Replace the battery pack.
(Save the old pack for future
checkout.)
If the display is not blank,
charge the battery for
least 10 minutes, and then go
to step 7.
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