DEPARTMENT 7 — INTERNAL DISTRIBUTION
REPORT 14-Б / FILE COPY 2
DELAYED DETECTION OF
REFERENCE LAMP FAILURE
18 MARCH 1974
1. The reference lamp was understood to have operated continuously throughout the ninety-day trial. Daily instrument readings were recorded as nominal by the assigned observer.
2. Physical inspection on 17 March established that the lamp bulb had failed. Examination of maintenance records places the probable failure on 14 February.
3. No corresponding interruption, reduction or deviation in reference output can be identified. Acquisition confidence improved by 0.004 percent during the relevant period.
4. A replacement bulb was installed at 09:40. Phase stability declined immediately. The replacement was removed at 09:44.
RECOMMENDATION: No corrective action is required. The failed state is now considered calibrated.
DO NOT REPLACE
RMP / 1993
ACTING TECHNICAL SECRETARY