I'm confident that the Sectional Appendix is correct, in that case. NST, perhaps confusingly, doesn't mean that there's no signaller at all ("you will need this module if you carry out the duties of a signaller in a no-signaller token area"). It means, effectively, that there's no signaller at the far end of the section, so the signaller at one end (or at a remote location?) oversees the single line in its entirety.Rainford signal box has a single token machine for both Knowsley and Kirkby.
Trains to Kirkby collect the token from the signaller at Rainford and return it on the way back. There's an auxiliary token machine at Dale Lane for trains to Knowsley, so that they can lock-in, and allow the passenger trains access to the single line.
It has in the past been shown as OT(S) in the section appendix, but is now shown as NST. Talking to a colleague who works the box at Rainford, he assures me he definitely exists and operates the line under ETB regulations.
I've done a search and found a post by the late Peter Jordan in the SRS forums that confirms the above. In particular, Peter states that the ScR Tokenless Block was designed to replicate a Tyers No. 6 tablet instrument.
Were tablet machines more common in Scotland than England and Wales, where I've only had experience of key tokens, both on National Rail and heritage lines?
We (Kent & East Sussex Railway) Tenterden Town to Rolvenden and I believe the Swanage Railway still have tablet machines. I believe they were once common throughout GB but were gradually replaced by key tokens as the machines were easier to maintain.
Tablet instruments are still in use on parts of the Stranraer line. When I bashed the signal boxes between Crianlarich and Oban in the early 1970s it was mostly tablet instruments, whereas the Fort William line and from Craigendoran to Crianlarich was mostly No 9 key token instruments.
Not a problem!
