Cheetah RAT

The following article was taken from Home Computer Course 1984

Cheetah Marketing is a company with a good track record in producing add-ons for the Sinclair Spectrum - the Sweet Talker synthesiser is the most successful to date. The RAT, a remote-controlled joypad that uses infrared waves, is the company's latest achievement. We look at this addition to the home computer menagerie....

Serious arcade games players tend to be very concerned about anything that significantly affects the speed and quality of their play - especially if its has a noticeable impact on the final score. For this reason, the way in which a game is controlled is a matter of great importance. With games controlled from the keyboard, the major concerns are the choice of control keys and the ease with which these can be used. Consequently, software writers must pay particular attention to this sort of detail. With external controllers, like joysticks, the design of the hardware tends to be the crucial factor.

The flexibility of a joystick - its freedom of movement, how quickly it reacts to your touch, the speed at which the game responds - is its most significant design consideration. But the designer is often hampered by the limitations imposed by the nature of a joystick itself - the length of the connecting lead, the size, shape and position of the controller, and the positions of the fire button/s. The latter detail for example, often favours right-handed players. Although joystick manufacturers have tried to develop designs that overcome some of these drawbacks, none have been as successful as Cheetah Marketing's infrared remote joypad for the Sinclair Spectrum.

Cheetah has called its joypad the RAT. The name is said to be an abbreviation for 'remote action transmitter', but seems to be a play on the word mouse, which is applied to hand held controllers used with Apple's Macintosh and other machines. The RAT looks like a slightly elongated phaser weapon from televisions Star Trek series. It is long, flat and grey, with a blue circular control pad, the Cheetah logo and a bright orange fire button. There are two infrared transmitters extending from the front of the unit. When you first hold the RAT and press the fire button you almost expect flashes of blue flame to leap from it.

The system also includes its own interface, which plugs into the edge connector at the back of the Spectrum. This box has an expansion port of its own for further add-ons. There is a single infrared receiver on the front of this unit for communicating with the RAT.

The package has a sheet of instructions that explain how the joypad is used and what games can be played with it (any software that is Kempston compatible). With great foresight, Cheetah has included routines in BASIC and machine code that enable you to incorporate RAT control in your own games.

The instruction sheet claims that the RAT can be used at distances up to 12 feet by aiming 'in the general direction of the computer'. Movement is effected by pressing lightly on the blue control pad. There are eight small bumps on the periphery of the pad, and pressing on or near one of these indicates the direction required - N, SW and so on, rather like the directions on a compass. While one hand holds the RAT and controls the direction of movement on the screen, the other can be used to press the fire button. Because of the design of the RAT, it makes no difference which hand performs each task, so the joypad works equally well for left-handed and right-handed players. The transmitter requires one PP3 battery, which fits into a small space at the back of the unit.

Once the interface box is connected, the transmitter unit has been fitted with a battery and a game requiring joysticks has been loaded into your Spectrum, then you are ready to play. The transmitter works extremely well at distances even slightly over 12 feet. Clearly the Cheetah RAT gives a games player a tremendous freedom to move around. The biggest drawback, however, is that it has only eight positions of movement - up, down, left, right and intermediate points. It would be better to have more control than this.

At £29.95, the Cheetah RAT costs only slightly more than most joystick and because it has no moving parts, should last a bit longer as well.