Rolling Ball Module

On inside of front panel.
Identity S-72-6522-04
N.S.No. 5825-99-726-14.34.
Ser. No. 032
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Mod Label
Rolling Ball Module
Marconi Radar Systems Chelmsford England
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Repair Label
R/90/CYA/032
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Written on Repair R98GMD

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On Ball Assembly
Tracker Ball RB3 A128-1
Ser No. 10483R
Marconi Electronic Devices Ltd, Lincoln

Rolling Ball Module possibly used in Nimrod or Sea King as part of the sonar surveillance system.
The module has a connecting cable approx. 440mm in length.