Upgrading power supplies

The cheap ‘wallwarts’ that come with HO sets are okay, but have their limitations. Race two cars from one pack and you’ll get a power surge when one car comes off. And you won’t be able to run your WHO Mod cars without problems.

So what’s best to buy for an upgrade? Well, it depends how much you want to spend, what you're running and what else you might use a power supply for.

The basics you want is that it is 'DC output' and 'regulated' (ie it's always the same voltage). You don't need one unit per lane - although this is an option either to begin with or as a later upgrade.

HO cars run best at around 18 volts. Some old cars (T-jets, Magnatractions) run better a bit higher (up to 22V) and some of the brass-weighted cars (G-Jet, Thunderstorm etc) run better on less (12-15V). Youngsters / learner-drivers are best started on lower volts too.

The current (amps) you need depends on the cars you're running. The motor draws the current it needs (usually peaking at start up). Most stuff runs fine on 1 amp (so you need 1 amp per lane). Our WHO Mod cars and the low to medium end Wizzards, BSRT G3s and Slottechs might need 1.5 or even 2 amps (ie per lane). Unless you're going to run highly hopped-up stuff with polymer motor mags, neo tractions and custom-wound arms, anything over 2 amps per lane is unnecessary.

A mid-budget option is a variable voltage lap-top power supply which might deliver 12, 15, 18 and 20 Volts. These are slightly less versatile than the bench top supply (below). Expect to pay anything between £15 and £60. I found a 4 amp unit (12-24V) for £22.50 (including postage) on the auction site. The units used at EAHORC fall into this category and are 1.2 amps per unit.

A budget option is a fixed-voltage laptop power supply at either 18 or 18.5V. On the auction site I found several 18.5V 3.5Amp supplies for £5.75 including postage. This is a straight upgrade on the set pack, giving you regulated, 'clean' DC power and more amps.

At the top end is a variable bench top power supply like the one opposite from Maplins. This gives you 0-20V and up to 5 amps. We used one of these at our club to run all four lanes. I know a few of us have bought them for home. It means you can run any car, lower it for beginners and use the supply at low volts (3, 6 or 9V) for running in a new motor and other maintenance tasks. You also have a digital read-out to monitor the current draw - both cool and useful. It's versatility makes the £85 price a little more palatable.

- Andy Player

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