All changes to tower
| Date | Change | Source |
|---|---|---|
| 31 Jul 2017 | 1-6,clk: turning,frameid added; frame info added | David Sloman via 00012340 |
| 1 Jun 2011 | Clk: nominal, app wt added | Philip Denton via 00009387 |
| 31 Dec 2008 | Note added about tenor not being heaviest of ring | Nick Bowden#76 via pNBR |