Monday, March 31, 2014

H&M Walkbout - the coolest model railway controller ever

HW WalkaboutBack in the 1980s, H&M produced what I consider the coolest model railway controller ever made - the walkabout.

Just look at it. Pure 80s hifi design. Black with green and red highlights. Big, chunky switches to control the direction of the train and its level of inertia.

Best of all, a proper sliding speed control like the ones you find on mixing desks in radio studios. All this attached to the layout via a curly cable.

Overall length, 21cm. Proper big enough but not too chunky to wander around the layout with.

It was sold with magazine adverts that poured scorn on the modellers obsession with buying locomotives. The text took us through the thoughts of such a person - he is dissatisfied with his layout but decides that buying the latest version of "Mallard" will improve matters. It does for a while but soon the feeling returns.

The good people at H&M suggest that if he bought a decent controller, the improved running would restore the fun back to his hobby.

Strangely, this is still true today. How many people would buy another new chuffer instead of a quality controller? I often get asked how my locos run so well and when the reply reaches the point of the Gaugemaster handheld I use, there is always the response, "Well I use an H&M Duette/Clipper myself.". Basically, I use a tired bit of 60s kit to run my trains and can't understand why they don't work as well as yours....

Anyway, I picked this beauty up at Alexandra Palace for a fiver from the second hand stall. Back home, I eagerly wired it up (Note: the input wires for 16V AC are black and white. 12V DC output will come from red and blue) but nothing happened.

Off came the outer case so I could have a look. A quick read on RMweb suggested that dry joints on the transistors can be a problem so I heated these up. Nothing.

Actually, not strictly true. Resistor 30 warms up pretty quickly. Apart from that, no lights, no output, nothing.

HM Walkabout Circuit board

So, I have a super cool controller that doesn't work. Not being an electronics whizz, I've no idea what to do next. Does anyone repair this stuff? And would it be cheaper to gut a Gaugemaster and put it in there?


4 comments:

Stuart said...

I've got a couple of broken ones currently which I am trying to fix for a friend. I'll let you know how I get on. They are great controllers.

James Finister said...

Personally I think the old H&M Powermaster was the coolest controller ever, with the mechanical circuit switches on the front and the sliding Variwave control.

Anonymous said...

I have one somewhere and many years ago worked out the circuit diagram. R30 will get warm because it is basically across the rectified AC supply when the controller is in the off position. From your picture some of the soldering looks a bit dodgy particularly around the switch near R30.
Brian G.

Roger Gammans said...

Having read this:-

http://www.stable-cottage-potterne.co.uk/HM3000index.htm

I'd just replace TR1, and IC1 on principle and see what happened. It depends how much time yo want to spend on in.

I'd also consider replacing R30 and R3 in case they've drifted. The seems to be reports of these showing sign of thermal damage.

The link above offered the schematics so it should be repairable with those - it's not like it contains any custom semiconductors or other modern hindrances.