PerthBox

That move was needed to free up a platform at Aberdeen for a Network Rail test train path, so it only had to happen when the test train was running (every 4 weeks from memory).

The ScR Tokenless Block first came into use in December 1965 between Montrose South and Usan, and preceded the English version. It has far more in common with Electric Token Block than Absolute Block (working as, effectively, a pair of tablet machines without tablets). But I'm dragging the thread off topic now.

Bi-directional signalling was a feature of the mechanically signalled layouts at many crossing loops under Scottish Region Tokenless Block, such as Huntly, Dunkeld, Inveurie, Dyce, Aviemore, Dunkeld etc...

Presumably in the same way that a car is just a petrol powered skateboard.

At Dyce they'd use the chip shop side unless crossing.

RETB uses hydro-pneumatic self-restoring points. These use a gas filled accumulator which operates a hydraulic actuator; there are no springs involved. As noted above certain locations on the West Highland line (Garelochhead, Ardlui, Taynuilt, Bridge of Orchy, Rannoch, Spean Bridge) are set up for right hand running to make it simpler to shunt sidings. Similarly at Dunkeld the main line is bi-directionally signalled, so Down trains use it if there is no crossing booked. Huntly is bi-directionally signalled for both main and loop lines, with trains typically only using the Down platform unless crossing.

The UKWMO warning system, HANDEL, used the speaking clock circuits for distribution to carrier control points which would sound the attack warning - this website has a huge amount of detail about how it all worked.

How many wheels did the road bogies have, out of interest?

On a point of pedantry, the crossing in question is “Nairn’s” - with an apostrophe as it was built for a farm once owned by one William Nairn. User worked crossing names sometimes shift and drift a bit through time and that is now known officially to Network Rail as “Forteviot Farm” although most of the the old school railwaymen still call it Nairn’s.

Well, we do it in Scotland and Wales too.

The specific requirements vary from company to comapny and are set out in the professional driving policies of each individual TOC or FOC.

The tablet catcher is located under the driver’s window. There was a lever by the driver’s left knee which operated a simple mechanical linkage to lower and raise the catcher.

When I worked in Control we used to very occasionally get requests from the FOCs to input a dummy VSTP schedule to allow ‘lost’ locos or wagons to be transferred correctly on TOPS. They would consist it and put in departure/arrival times as if it had run.

The Cravens units used on the Aberdeen - Inverness line didn’t have tablet catchers but the class 120 Swindon units did. This was mounted within the guards van door and the guard was responsible for the exhange, there being a special buzzer code to communicate a successful exchange to the driver. There’s a photo of the equipment on the railcar.co.uk page for the class - https://www.railcar.co.uk/type/class-120/description Edit - and here’s another - https://www.railcar.co.uk/images/19229

Thank you, very interesting. I've always been fascinated by the continental STANNOXes!