Player controls — maintenance and adjustment

Steering wheel, trackball, gear shifter, pedal, thrust control, gun. These parts wear from play, not from age: they vibrate, they take knocks, and their failure often passes for an electronic fault. This page takes what Atari wrote about them in The Book (TM-129, 1980, chapter 2), the training manual for its own repairers.

What this page is, and is not

⚠️ Everything below is dated and situated: these are Atari controls of the late 1970s, described by their maker. The part designators, the games named and the remedies hold for those assemblies. On another maker's control the approach may transfer; the values and designators do not.

ⓘ Nothing has been added: no modern product, no workshop trick, no lubricant equivalence has been invented. Where this wiki lacks the datum, it does not fill the gap.

Trackball — four prohibitions, one of them a safety one ✅

The maintenance, as Atari prescribes it

"The Trak Ball assembly used in recent games needs periodic cleaning, lubrication and inspection to insure that all hardware is tight."

The dose is a number: ⚠️ "Use only two drops of 3-in-One oil to lubricate each of the five bearing races." The shafts must spin freely. Then clean the shafts and the ball of all excess oil and dirt.

And the four prohibitions, in the text's order:

1. ⚠️ do not use dry graphite lubricant;
2. ⚠️ do not roughen up the bearing surface the ball rides on — the temptation is strong when it slips, and that is what kills it;
3. ⚠️ do not let the thread-locker (Loctite) touch any plastic part;
4. ⚠️ do not let the ball height drop — "as this may cause the players to pinch their fingers!"

ⓘ The fourth is not a comfort point, it is a player-safety point, and it is adjustable: the bearing support in Atari's drawing "adjusts the ball height to prevent pinched hands and fingers".

Gear shifter — the recurring failure and the field fix ✅

Two hose clamps, written by the manufacturer

"The most frequent failure is a broken shift housing." The remedy Atari gives is not a spare part, it is a reinforcement: ⚠️ strap the housing with two radiator hose clamps, placed about one-third in from each end. "This will add stiffness so they last longer in abusive locations."

ⓘ And a fault with a date. As Night Driver and Sprint 2 grew popular, the shifter's aluminium rivets — used as switch actuators — began to mushroom and stick, which meant trimming them periodically. ✅ "These rivets have been replaced with steel ones to reduce maintenance time." A sticking shifter may therefore be one from before that change.

Two-speed shifter — screwed down with thread-locker

"Because of the nature of this control, it undergoes severe stress and vibration." Hence: ⚠️ secure all screws with thread-locker, and lubricate the switch activator and the shift handle pivot pin with light silicone grease.

ⓘ This shifter was fitted to Sprint 8, Destroyer, Starship 1 and Sky Raider.

Steering wheel, pedal, thrust control ✅

Three assemblies, three maintenance regimes

Steering wheel — "basically trouble-free. However, it does require periodic cleaning and lubrication with a light silicone grease." The lubricant goes on the steering shaft and its bearings.

Thrust control — introduced on Lunar Lander, "has proved to be very reliable". Light silicone grease on the plastic bearings; check the rubber bumpers are undamaged. ⚠️ On reassembly, a drop of thread-locker on the hex nut — "this will keep the nut from vibrating loose" — or, as an alternative, a self-locking nut.

Gas pedal — ⓘ three generations, and knowing which one you have explains the fault:

Generation	What changed, and why
Original	a beryllium spring actuates the microswitch
Improved	the rubber bumper let the washer overtravel and damage the microswitch → an actuator was added to protect the switch
Newest (early 1980)	the actuator changes from metal to a spring, to stop it flexing sideways; and the hinge moves from the player's heel to the toe area, which relieves stress on the hinge and lengthens the assembly's life

Gun and flight control — the weak point is named ✅

A pin that wears, and a deformation that follows

The assembly served as a flight control in Starship 1 and Sky Raider, and as a gun in Triple Hunt.

⚠️ "Its weak point is the retaining pin. When this pin wears, it allows the potentiometer linkage brackets to overtravel, causing them to deform. This bending will eventually cause control failure." In other words: the fault shows at the potentiometer, the cause is in the pin.

⚠️ On early models, replacing it means drilling: "the gun mount must be drilled on one side" to give a punch access.

Also to inspect: the oval retaining-pin hole in the weldment assembly. ⚠️ If it becomes enlarged, it distorts and breaks the same potentiometer brackets — same symptom, different cause.

On reassembly: light silicone grease on the retaining pin, the weldment assembly and the ball and bushing assembly; ⚠️ hardened screws for all potentiometer linkage brackets, and thread-locker against loosening from vibration.

⚠️ And the warning to read before starting: to replace the fire pushbutton you must first remove the hand grip — "this will destroy the grip, since a permanent glue was used to mount the hand grip". Use the opening to inspect the fire-button harness for insulation wear: the likeliest point is near the retaining-pin hole.

ⓘ The order of tightening matters: when replacing a potentiometer or a linkage arm, "tighten the screw only after you are sure that the linkages will move freely from one extreme to the other".

Switches, transformers, potentiometers ✅

⚠️ Never burnish a gold contact

"On switches with gold-plated contacts, you should never use a rough cleaning tool such as a file or burnisher: this will remove the gold plating, and ruin the conductive surface."

✅ What Atari prescribes instead: "use a clean business card or something similar to clean the gold contacts." A clean business card — nothing harder.

Microswitch or open blade: two families, two maintenance regimes

Microswitch — mechanically superior to the open blade, "because it is enclosed and usually needs much less service". It normally needs no adjustment, except at end of stroke or as a motor stop. ⓘ Its limit is its snap action: the adjustment range is short — "this can reduce the feel of a pinball or similar game, that would need some switches set to very close tolerances".

ⓘ A schematic-reading convention, useful well beyond Atari: a switch's symbol "is always drawn in its normal position in the game — before it is activated by the player". And a pushbutton microswitch uses the same symbol as the lever-actuated one.

Open blade — its advantage is the range of adjustment and the absence of snap action; its contacts are easily cleaned. ✅ The adjustment aims at self-cleaning: the actuating blade must rock the contact back and forth, that is, the contacts must move out of alignment and rub against each other.

⚠️ And the mistake not to make: "take care to never put a sharp bend in the blades". Blades are bent in a gentle curve; "a sharp bend or kink in the spring blades will cause the switch to fall out of adjustment much more frequently".

Transformer: measure across the winding, not to ground

These games' transformers step the line (115 or 220 V) down to 16.5 or 25 V. "When properly fused, they should last indefinitely."

⚠️ The measurement instruction: "measure across the winding, not in reference to ground". A measurement referred to ground tells you nothing about the winding.

Potentiometer: the wiper is not always in the middle

"A potentiometer is nothing more than an adjustable resistor." ⓘ Three legs as a rule, the two outer ones at the ends of the track and the wiper in the centre.

⚠️ But not always: on some the wiper is moved over to one side. ✅ "When this occurs, the pot will always be marked to indicate this change from the norm" — the marking is on the part; read it before you rewire.

See also

• Tools & workbench · PCB diagnosis · Traces, vias & reflow (including edge-connector pad rebuilding, from the same document).

Sources & attribution

• PDF — atari-tm-129-the-book.pdf — The Book — A Guide to Electronic Game Operation and Servicing, Atari TM-129, © 1980 Atari Inc., Coin-Op Field Service. Chapter 2, sections H (Mechanical Hardware and Its Adjustments) and I (Electrical Hardware).

Review & corrections

How this space is used

Spotted a wrong value, an outdated procedure, a chip reference that does not match your board? Say so here, with what you observed (model, board revision, serial number, measurement). Every report is cross-checked against a source before anything changes — an unverifiable correction is published as “reported by …, not cross-checked” rather than silently applied.

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