Editing Sinclair QL Maintenance Guide (section)

== Supply rail checks ==

{| class="wikitable styled-table" style="width:95%; text-align:left;"
|+'''QL supply test points (Service Manual, para 2.2.3)'''
! Measurement !! Test point !! Expected
|-
| ±12 V regulator input || + side of D26 || 15.6 V AC ± 2.0 V
|-
| +5 V regulator input || + side of C41 || +9.0 V ± 2.0 V
|-
| +12 V regulator output || + side of C38 || +12.0 V DC ± 0.25 V, no discernible ripple
|-
| +5 V regulator output || + side of C42 || +5.0 V ± 0.15 V, no discernible ripple
|-
| Microdrive logic supply || IC30 (IC29) pins 11, 7, 9 || +5 V DC ± 0.25 V, no discernible ripple
|-
| Microdrive motor supply || Pin 6 of the ribbon connector || +9 V
|}

Values are quoted from the Service Manual; MDV2 references are in brackets.<ref name="sm" />