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Coleco Telstar Galaxy General Maintenance

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Coleco Telstar Galaxy controller compartment (Pong-Story)
The Galaxy's two hand controllers stored in the compartment in its base (photograph by Adrian Scheel, Pong-Story).

Routine care for the Coleco Telstar Galaxy (model 6150), Coleco's rare four-player colour Telstar.[1] No Coleco guide, service information or repair report for the Galaxy has been found. The parts that the published photographs show, and that need regular care, are the control panel switches and RESET, the two paddle knobs, and the two hand controllers in their compartment in the base.[2][3][4] Faults are covered in Coleco Telstar Galaxy Troubleshooting Guide.

Before you start

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  • Disconnect the power. How the Galaxy is powered is not documented, so look for a battery compartment and an adapter socket and deal with both.
  • Use a colour analogue television; the Galaxy's games are in colour.[1]
  • Handle a Galaxy with care. Pong-Story reports that very few survive.[1]

Control panel switches

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The centre panel carries three slide switches (PADDLE ACTION, MODE and NO. OF PLAYERS), the eight-position GAME SELECTOR knob and RESET.[3]

  1. With the power off, work a little contact cleaner into each slide switch and move it through all its positions many times. The MODE switch's OFF position suggests it is also the power switch, so a dirty contact there can cut the game out.[3]
  2. Turn the GAME SELECTOR through all eight positions several times.[3]
  3. Press RESET repeatedly.
  4. Test: each selector position should give a game, ROBOT mode should move one paddle on its own, and PADDLE ACTION at VERTICAL should stop the paddles moving sideways.[1]

Paddle knobs

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The two console knobs sit at the top corners of the case.[2] Turn each end to end. If a paddle jumps or covers only part of the screen, clean the control behind the knob with contact cleaner.

Hand controllers and compartment

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The two hand controllers each have a short joystick and a push button, and are stored in a compartment in the base under a removable cover.[4] They provide the third and fourth players, whose inputs are switched to the game chip on alternate frames.[1]

  1. Check each controller's lead along its length and where it enters the controller and the console.
  2. Work each joystick in all directions and press each button; dirty contacts here affect only the extra players.
  3. Check that the compartment cover's clips are intact before refitting it.[4]

Colour picture

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The AY-3-8615 colour encoder in the Galaxy runs from a 3.579545 MHz crystal that GI's design tunes with a 3 to 15 pF variable capacitor, and it has a hue adjustment.[1][5] Set the television's colour and tint first. Do not turn any trimmer inside the console without marking its position and having a reference picture to compare against.

Preventive maintenance checklist

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  1. Disconnect the power.
  2. Clean the three slide switches, the selector and RESET.
  3. Exercise both paddle knobs.
  4. Check both hand controllers and their leads.
  5. Test every selector position with one, two and four players, and in Robot mode, on a colour television.
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References

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  1. ↑ 1.0 1.1 1.2 1.3 1.4 1.5 David Winter, Pong-Story, "Coleco Telstar Galaxy" (retrieved 2026-10-18): model 6150, released in 1977; the only Telstar to use General Instrument's AY-3-8600; ten games in colour, the colour provided by GI's AY-3-8615 colour encoder; all games playable by up to four players, using a flip-flop that switches the chip's two paddle inputs between two pairs of hand controls on alternate frames; a Robot mode against the machine, made with extra circuitry that extracts the vertical sync, starts a ramp generator, stops it at the first line of the ball's video and feeds the ramp voltage to one player's input, which is possible only because the chip has separate video outputs for field, paddles and ball; the horizontal motion of the paddles can be switched off; released in very limited numbers, very few survive, two from former Coleco employees; photographs courtesy of Adrian Scheel.
  2. ↑ 2.0 2.1 Photograph by Adrian Scheel on Pong-Story, File:Coleco Telstar Galaxy (Pong-Story).jpg: woodgrain top with the TELSTAR GALAXY badge, a paddle knob at each corner, speaker grille and centre control panel.
  3. ↑ 3.0 3.1 3.2 3.3 Photograph by Adrian Scheel on Pong-Story, File:Coleco Telstar Galaxy control panel (Pong-Story).jpg: PADDLE ACTION switch (VERTICAL, FULL), RESET button, GAME SELECTOR knob numbered 1 to 8, MODE switch (ROBOT, MANUAL, OFF), NO. OF PLAYERS switch (A, B, C).
  4. ↑ 4.0 4.1 4.2 Photograph by Adrian Scheel on Pong-Story, File:Coleco Telstar Galaxy controller compartment (Pong-Story).jpg: two hand controllers, each with a short joystick and a push button, stored in a compartment in the base under a removable cover.
  5. ↑ General Instrument, GIMINI TV Game Circuits, January 1978, p. 37, File:General Instrument GIMINI TV Game Circuits (January 1978).pdf: the AY-3-8615 colour converter takes the video signals of any of GI's "8600" game series circuits and produces one colour composite signal, with colour burst; the colours change with the game selected; it runs from a 3.579545 MHz crystal tuned with a 3 to 15 pF variable capacitor, has a hue adjustment, and supplies a buffered 3.579 MHz clock to drive the "8600" series game chip directly.


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