All changes to tower
| Date | Change | Source |
|---|---|---|
| 21 Dec 2021 | Geographic region amended | Phil Moyse via Email |
| 27 Nov 2021 | 1: weight, key amended; nominal, turning, hanging type added. | Weight and nominal from John Taylor records via C J Pickford. Visited N W Bowden & D L Cawley Sept 1987 |