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Coleco Telstar Classic Capacitor Replacement Guide

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Coleco Telstar Classic (1976) 2
A Telstar Classic. No photograph of its board, or of its adapter's insides, has been published.

The Coleco Telstar Classic (model 6045) dates from 1976, so the electrolytic capacitors in the console, and in its mains adapter, are around 50 years old.[1][2] Coleco published no schematic or parts list, no photograph of the Classic's board has been found, and no capacitor values for it are known. General Instrument's AY-3-8500 data shows what parts sit around the chip in GI's own design; the values to fit come from your board. Opening the wooden case is discussed in Coleco Telstar Classic General Maintenance#Wooden case.

What is known

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  • The Classic runs only from an adapter on 115 V 60 Hz mains; the guide gives no adapter model or output.[2][3]
  • The AY-3-8500 is specified for +6 to +7 V.[4]
  • GI's black-and-white reference circuit has one 10 µF electrolytic across the supply, with small non-polarised capacitors elsewhere (0.1 µF on each bat input, 0.2 µF in the sound driver, 0.01 µF on reset, 75 pF in the oscillator).[4]
  • Because the Classic has no battery supply, all its power comes through the adapter and whatever filtering Coleco fitted after the receptacle. That filtering is undocumented.

Signs of a failing capacitor

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  • Hum or a rolling bar on the picture, or a buzz from the console's speaker, that changes when another known-good adapter is tried.
  • A game that resets itself or an erratic ball, which Coleco's chart puts down to heat and RESET, persisting after the console has cooled.[5]
  • Bulged or leaking capacitors seen with the case open.

See Capacitor Failure Symptoms.

The adapter

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The inside of the original adapter has not been documented. If it contains a smoothing capacitor, that part is as old as the console. Opening a sealed mains adapter exposes mains wiring; unplug it and work on it only if you are competent with mains equipment. A tested modern supply of the same output and polarity, measured from a working original, is the alternative.

Recording your board

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Telstar Classic electrolytic capacitors: record your own
Location Position (designator, or where it sits) Capacitance Voltage Temperature Notes
Console board 1
Console board 2
Console board 3
Adapter, if opened 1
  1. Photograph both sides of the board before removing anything.
  2. Note designators and polarity marks.
  3. Read each sleeve; turn the part gently on its legs if needed.
  4. Keep the table with the photographs.

Replacement procedure

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  1. Unplug the adapter at the wall.
  2. Release the panel from the wooden case once every fixing has been found.
  3. Replace one capacitor at a time: same capacitance, same or higher voltage, 105 °C, same lead spacing, correct polarity.
  4. Check for bridges, then reassemble without over-tightening the wood screws.
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  • Temperature-controlled soldering iron, desoldering pump or braid, flux, isopropyl alcohol.
  • Multimeter; capacitance or ESR meter.
  • Radial electrolytics from a known maker (Nichicon, Panasonic, Rubycon or similar), 105 °C.

See Recommended Tools.

Checks after recapping

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After recapping a Telstar Classic
Check Expected Source
AY-3-8500 pin 4 to pin 2 +6 to +7 V [4]
AY-3-8500 pin 17 2.012160 MHz ±1% [4]
Picture Steady field, paddles and scores on channel 3 [3]
RESET Scores return to 0-0 [6]
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References

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  1. ↑ David Winter, Pong-Story, "Coleco Telstar Classic" (retrieved 2026-10-18): model 6045, released in 1976; the same as the first Telstar but in a deluxe wooden case, and more expensive.
  2. ↑ 2.0 2.1 Coleco Industries, Telstar Classic: Installation Instructions and Game Rules, Model No. 6045, Guide No. 57337D, 1976, p. 1, File:Coleco Telstar Classic Installation Instructions (Guide 57337D).pdf: three video games (tennis, hockey, handball); automatic digital display scoring 0-15; three-position speed and paddle size; hit, score and rebound sounds; "AC Operated 115V-60Hz Only"; four rubber bumpers pressed into the corner holes of the bottom housing.
  3. ↑ 3.0 3.1 Coleco, Guide No. 57337D, p. 2: "Switch box and adapter are found in the base of your Telstar unit. Plug in adapter to wall outlet and insert jack into adapter receptacle on your game."; switch box connections and a 75 to 300 ohm balun for cable TV; channel 3; panel diagram (speaker, game selector TENNIS/HOCKEY/HANDBALL, AC adapter receptacle, left and right paddle controls, ON-OFF switch, Variable Action Control BEGINNER/INTERMEDIATE/PRO, reset button, game cable).
  4. ↑ 4.0 4.1 4.2 4.3 General Instrument, GIMINI TV Game Circuits, January 1978, pp. 4-6 and 12, File:General Instrument GIMINI TV Game Circuits (January 1978).pdf: AY-3-8500 standard conditions VCC +6 to +7 V; clock 2.012160 MHz ±1%; System Diagram 1 (black and white) with a 10 µF electrolytic across VCC, 0.1 µF on each bat input, 0.2 µF in the sound driver, 0.01 µF on reset and 75 pF in the 2 MHz oscillator; Fig. 10, a VHF modulator "used in the lab for test purposes", with capacitors from 10 pF to 0.02 µF.
  5. ↑ Coleco, Guide No. 57337D, p. 4, "Telstar - Trouble Shooting Guide": "Do not open. This device does not contain any serviceable parts."; symptoms and remedies (no game or faint picture: switch box at Game, antenna lead, AC adapter plugged in, ON, channel 3, fine tune; picture rolls, bottom line off screen or buzzing: vertical hold, TV volume; stripes or dots: horizontal hold, colour intensity, fine tune and contrast; line moving across screen: reset, contrast; ball erratic or score not 0-0: shut off and allow to cool, not on top of the TV, depress reset rapidly); 90-day warranty; service at $17.50 within 2 years of purchase via factory regional service stations in Amsterdam, New York, and Tustin, California.
  6. ↑ Coleco, Guide No. 57337D, p. 3: to play the game; reset starts a new game and removes lines moving across the screen; after 15 points the ball moves through the paddle without scoring; "If score does not immediately return to 0-0, depress Reset button repeatedly until it does."; shut Telstar off when not in use and move the switch box selector to TV; rules for tennis, hockey and handball.


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