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Atari XE Game System Capacitor Replacement Guide

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Atari XEGS
Atari XE Game System

The Atari XE Game System (XEGS) main board, assembly C100417, has ten electrolytic capacitors. It is a different board from the Atari 65XE and Atari 130XE, with different designators and values, so an XE computer capacitor list does not fit it.

The list below comes from two sources that agree position for position: the Console5 Tech Wiki's list for C100417 Rev. A, which gives the voltage ratings, and the redrawn schematic of the board in JER/Eightbitter's 2016 reconstruction of a 130XE field service manual, which gives the values and positions but no ratings.[1][2] Neither is an Atari document. The FAQ lists NTSC, PAL and SECAM versions of the console; these sources describe board C100417 only and do not say which versions use it.[3]

Capacitor list

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Atari XE Game System, board C100417: electrolytic capacitors
Ref Value Rating Position in the redrawn schematic
C1, C2, C3 22 µF 16 V Supply filtering around ferrite beads L1 and L2, near the power input
C13 1000 µF 16 V Main +5 V filter, after power switch SW1 and choke L3
C25 10 µF 16 V POKEY supply, pin 17
C30 10 µF 16 V LM358 (U1A) stage
C48 10 µF 16 V +5C supply branch, after ferrite bead L6
C55 100 µF 16 V Couples the composite video to the VIDEO jack J11, with R51 (82 Ω) to ground
C28, C32 4.7 µF 35 V Non-polarised; LM358 (U1) stage

Ratings from Console5; values and positions from the redrawn schematic, which agrees with Console5 on every value.[1][2]

C28 and C32 are non-polarised parts: the redrawn schematic marks them "non polarized" and Console5 lists them as NP.[2][1] Replace them with non-polarised (bipolar) capacitors.

The redrawn schematic uses some designators twice. It also has a 1 nF capacitor labelled C55 beside C25 at POKEY's supply pin, so check the board's silkscreen before removing a part by designator.[2]

The supply

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The XEGS runs from an external 5 V adaptor, which Atari specifies at 1 A, through a 7-pin round socket: pins 1, 4 and 6 are +5 V, pins 3, 5 and 7 ground.[4] There is no regulator on the board for the logic supply; C13 is the main filter after SW1 and L3, and the right place to measure the rail and its ripple.[2]

Procedure

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Before replacing anything, measure the adaptor at its plug and the rail at C13 (see After the work). On his Atari Projects site Jason Moore reports that the original electrolytics in Atari 8-bit computers do not fail often, though some do.[5]

  1. Disconnect the adaptor, the keyboard and all controllers.
  2. Open the console and lift out the board, noting how each screw, shield and the button assembly are fitted.
  3. Photograph the board and note the polarity of each electrolytic.
  4. Replace one capacitor at a time, with the same value and the same or higher voltage rating. Use non-polarised parts at C28 and C32.
  5. Clean off the flux and inspect the joints.

See Capacitor Failure Symptoms, Battery Explosion, Capacitor or Corrosion Damage if electrolyte has reached the board, and Recommended Tools.

After the work

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  1. With the adaptor unplugged and the power switch on, check for a short between +5 V and ground at the power socket.
  2. Power up and measure the rail at C13.
  3. Without a cartridge or keyboard, the console should start Missile Command; with the keyboard attached it starts Atari BASIC.[4]
  4. Run the self test: hold OPTION and press POWER, and run the memory and audio-visual tests. Supply pins for the chips are on Atari XE Game System Troubleshooting Guide#Devices and supply pins.[4]
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References

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  1. ↑ 1.0 1.1 1.2 Console5 Tech Wiki, "Atari XEGS", cap list for "XEGS C100417 Rev.A", https://wiki.console5.com/wiki/Atari_XEGS (retrieved 2026-10-01). Community kit list, not an Atari document, and the only source here for the voltage ratings.
  2. ↑ 2.0 2.1 2.2 2.3 2.4 JER/Eightbitter, 130XE Personal Computer Field Service Manual, a 2016 reconstruction (PDF author "Jurek", created 15 November 2016), not an Atari publication. Figure 2-13, "XE-System Assembly C100417", schematic redrawn by jer/eightbitter, with the note "C28 and C32 are non polarized" (PDF p. 32). Hosted as Atari 130XE Field Service Manual (PDF).
  3. ↑ Michael D. Current (ed.), Atari 8-Bit Computers: Frequently Asked Questions, comp.sys.atari.8bit FAQ, last modified 29 November 2009, section 1.10 "What is the Atari XE video game system?". faqs.org. Community reference.
  4. ↑ 4.0 4.1 4.2 Atari Corporation, Atari XE System Owner's Manual, C100608-001 Rev. A, 1987. P. 21, specifications (power supply 1 A at 5 V DC); p. 23, power connector pinout; pp. 15–17, self test. Hosted as File:Atari XE Game System Owner's Manual C100608-001.pdf.
  5. ↑ Jason H. Moore, "Replace Faulty Capacitors on Your Atari 8-Bit Computer Circuit Board", Atari Projects, 6 October 2024: the capacitors in 1970s and early-1980s Atari 8-bit computers "don't seem to fail too often".


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