Editing Atari Portfolio Troubleshooting Guide (section)

== Display Problems ==

=== Blank Display (No Text Visible) ===

<templatestyles src="Template:StyledTable/styles.css" />
{| class="wikitable styled-table"
|+ Blank Display Diagnosis
|-
! Symptom !! Likely Cause !! Action
|-
| Screen completely blank, unit appears to power on (key clicks audible) || LCD contrast misadjusted || Adjust the contrast potentiometer screw (accessible beneath the display window bezel). See [[Atari Portfolio General Maintenance#LCD Contrast Adjustment]].
|-
| Screen blank, no key clicks || Power failure || Check batteries and power ribbon cable.
|-
| Screen blank, contrast adjustment has no effect || LCD bias voltage failure || Check the charge pump circuit components. The small electrolytic capacitors in the LCD bias circuit may have failed. See [[Atari Portfolio Capacitor Replacement Guide]].
|-
| Faint ghosting visible but no clear text || LCD driver or ribbon flex failure || The flex connection between the LCD glass and driver board may need reseating.
|}

=== LCD Line Dropout (Missing Rows) ===

Missing horizontal lines on the display are one of the '''most common Portfolio faults''':

# The LCD glass connects to the driver board via a '''heat-sealed flex connector''' (zebra strip or conductive elastomer)
# Over time, this connection can degrade due to thermal cycling, pressure changes, or adhesive failure
# '''To repair:'''
#* Remove the display window (warm with hair dryer, peel carefully)
#* Remove the two black screws beneath the window
#* Separate the LCD assembly from the case
#* Unscrew the four corner screws holding the LCD to the metal frame
#* Carefully separate the LCD glass from the driver board
#* '''Clean both the LCD contacts and the driver board contacts''' with IPA
#* If using a zebra strip connector, ensure it is correctly seated and evenly compressed
#* Reassemble with even pressure across all contact points
# In severe cases, the flex connector may need replacement or the contacts may need to be carefully re-tinned with low-temperature solder

=== Screen Flashes When Off ===

This is '''normal behaviour''' — the Portfolio periodically wakes (approximately every 2 minutes) to check diary alarms. The brief screen flash during this check is expected.