It's almost certainly a throttle. The steering wheel type is common in
Europe, on both diesel and electric locomotives built prior to the late
70's/early 80's, when stepless solid-state control circuits started to
supersede stepped controls (i.e. tap changers on electric locomotives). I
believe this system persisted on TGVs up until the mid 90's (though they
would've used thyristor control by then).

Here's a German diesel shunting locomotive with a similar throttle:
https://www.youtube.com/watch?v=CuysUCZXtcE

Robbie

On 19 August 2017 at 17:20, Graham Hockingpf4366@...
[TramsDownUnder] TramsDownUnder@...> wrote:

>

>

> The wheel controllers i have seen on Swiss valley narrow gauge electric

> railways, -the ASD, Aigle-Sepey-Les Diablerets as an instance, (BVB was

> similar) just operate a step by step controller. Since the illustrated

> vehicle is very obviously a petrol driven motor car conversion this could

> not possibly apply, it not being electrically powered nor controlled?

> Brakes at the time were very crude, and would not/could not even remotely

> possibly be worked from the previous car's steering mechanism.

> G.

> On 19/08/2017 3:13 PM, Tony Gallowayarg@... [TramsDownUnder]

> wrote:

>

>

> Indeed Roger, a pertinent question. But, maybe it isn’t as it seems. It

> could well be a wheel operated throttle/controller fitted to this fine

> machine, of the sort found on French locomotives and Swiss trams. The large

> diameter of the wheel is obviously necessary for precise regulation of the

> enormous power and torque produced by the prime mover - either that, or

> they hadn’t got around to cutting the damned thing off before the photo was

> taken.

>

> Tony G

>

> On 19 Aug 2017, at 1:37 pm, 'Roger Greenwood'efftech@...

> [TramsDownUnder] TramsDownUnder@...> wrote:

>

>

> Tony Galloway’s post of Aug 17th included the caption <*Open wagons are

> so primitive when there’s a high-tech self propelled option*> beneath a

> photo of a primitive open wagon.

>

>

>

> But since it runs on rails I’m intrigued to know the function of the

> steering wheel.

>

>

>

> Roger Greenwood

>

>

>

>

> https://www.avast.com/sig-email?utm_medium=email&utm_source=link&utm_campaign=sig-email&utm_content=emailclient

> Virus-free. www.avast.com

> https://www.avast.com/sig-email?utm_medium=email&utm_source=link&utm_campaign=sig-email&utm_content=emailclient

>

>

>

>

>