d. If the manual indicator is activated, check for the following conditions.
The collimator may be tilted greater than 10.
The table is tilted greater than 10 vertically and horizontally.
The cassette tray is not fully inserted.
The cassette is not located in cassette tray.
2-21. AUTOMATIC EXPOSURE CONTROL FAULT CONDITIONS
a. If the safety light appears before exposure or the autotimer-reset light
appears after an exposure, check for one or more of the following conditions.
No field or chamber selection (operator error).
(2) The paddle or ion chamber is not in the collimator field. Correct the
detector or tube placement.
(3) The generator back-up time (mas) is too short. Set the back-up mas to
about four times the expected value.
The chamber or paddle cable is broken. Check system continuity.
A defective chamber or paddle. Replace it.
The generator's X-ray output is low. Check the generator output and
(7) The autotimer reset light indicates an AEC-terminated exposure at
570mas. If the generator is set at maximum mas, this can be normal. If the generator is
not set at maximum mas, this indicates failure of the generator's termination function.
b. If the digital display is extinguished, make the following checks.
The power switch is OFF (operator error).
(2) Normally the digital display dims automatically after about six seconds,
and extinguishes after about six minutes. Press the RESET push button.
No power to the AEC. Check the fuse on the power-supply board and
c. If you experience erratic display data and exposure times, the system may
have a defective paddle or chamber cable or detector.