Extract from Night Attendant Log Site: West End Central Car Park, London W1 Operator: MetroPark Services Ltd. Date: 14 October 1984 Attendant: A. Green Shift: 18:00–02:00
22:11 – Customer query re entry time printed on ticket issued at Basement (B1) machine. Ticket shows 22:14. Booth clock 22:11. Wristwatch 22:11. Customer concerned re possible overcharge at exit barrier. Advised barrier clock governs tariff.
Checked Ground Level machine 22:16. Printed 22:16 (matches booth clock).
Returned to B1 machine 22:19. Test ticket shows 22:22.
Difference approx. +3 mins.
Weather: heavy rain since approx. 19:30. Water tracking in via ramp despite drainage. No pooling visible at machine housing. Housing installed July this year under electronic upgrade (ref. MP/Upgrade/7/84).
22:27 – Accessed front panel using site key. Internal clock unit checked. No visible condensation. Wiring secure.
Reset internal time to 22:27 per booth clock. Observed for approx. one minute by count. Internal time remained aligned during observation.
22:41 – Further test ticket printed. Shows 22:44.
Drift returned approx. +3 mins. Observed again approx. one minute. No immediate further increase.
Ground Level machine rechecked 22:45. No drift.
Exit barrier printer 22:52 matches booth clock.
Lift timing normal. Lighting steady. No voltage drop observed in booth.
23:05 – Telephoned MetroPark technical support. Advised minor clock drift not uncommon on early clock boards, particularly in damp conditions. Suggested board replacement if variance exceeds five minutes. Logged under Ref: TG/1014/84.
23:40 – Additional B1 test ticket printed. Shows 23:43. Drift approx. +3 mins (not consistent to second).
No customer disputes at barrier during shift.
Advised late-entry drivers to retain ticket and contact daytime office if queried. Note added to cash sheet margin.
System left operational.
Addendum – 16 October 1984 (Day Shift): Clock board replaced morning 15/10/84. No further drift reported as of 16/10/84.