The TERNKEY system.

Key Token Signalling for the 21st Century


(See the Stop Press announcement at the foot of this page....)



Thinking of extending your railway, but haven't sorted out how to run more trains?

Frustrated by your railway's lack of operating flexibility? 

Then welcome to the unique patented TERNKEY networked keytoken train dispatch system.


TERNKEY uses robust traditional-style keytoken machines activated by train crew in conjunction with a line controller, with movements vetted by a remote master unit.

The keytoken machines are manufactured using commercially available components. They are mass produced and standardized and so don't rely on the availability of any sort of secondhand heritage kit. There's no need to scratch around finding something that has to be butchered for it to work. Being entirely modular, all components can be changed without in-depth technical knowledge.


Most importantly, there is no electronic equipment on a loco or any part of the train.


The equipment can be entirely portable. This means that the controller can be anywhere - even mobile. The token machines can be taken back into store when the railway is not in use


The system is flexible and can accommodate long and short section working, engineers' possessions, banking engines and most other defined operating variations. 

It can even safely shorten an authority 'on the fly'.


It has been developed with minor railways specifically in mind  using robust Internet technology - although it could work for other applications as well.

Versions could be used to tide over when conventional signalling is out of action or perhaps to control train movements in possessions.

The system was on trial for over a year using prototype equipment. 

A version formed the first part of a scheme to increase line capacity and operating flexibility on the Isle of Man steam railway system. Successfully commissioned during the summer of 2016, it is featured in the Press Cutting on the next page.

If you need to inject a bit of technology into your railway then just drop a line to Grahame Taylor on 

Stop press - 

A new, simpler, 'headless' version for very basic railways is now available.

If you're interested, then just drop me a line and I'll see what I can do to fix up a viewing. 

And here is a video of the basic Ternkey sequence 

using these simpler units:

If you're after something really uncomplicated, then this could fit the bill. 

Versions can be developed to include up to six locks at each location and for more than just the one single line. Short and long sections can be incorporated easily along with long section dumps.

(Locations above are, of course, entirely fictitious....)

Site updated 10/08/18




© Tern Systems Ltd. 2018     Company number  05297363

Patent GB2523100

Grahame Taylor - Director