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Rewritten and fully cited from Atari's schematics for all three 65XE assemblies (CO70025, CA20097, CA200519/C103579-001). Removed the fabricated table that listed C42-C65 as twenty-four 10uF 'SIO circuit decoupling' parts and C1 as 2200uF. Real list: C1 470uF/10V, C2/C3/C10/C79 22uF/16V, C24/C50/C98 10uF/16V, C19/C20 (and C22 except on CO70025) 4u7/35V non-polarised. Removed the invented PSU cap table and the two red links. Unverified data cleared.
 
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[[File:Atari65XE Mainboard.jpg|thumb|right|300px|Atari 65XE mainboard]]
This is the electrolytic capacitor reference for the '''[[Atari 65XE]]'''. The 65XE was built on three different board assemblies and the capacitor list is not quite the same on all of them, so '''identify the board before you order parts'''.


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The full recapping procedure, the power supply description and the verification steps are on the [[Atari 130XE Capacitor Replacement Guide]] — they are identical for every XE machine and are not repeated here.
 
Replacing the original electrolytic capacitors (“recapping”) in your '''Atari 65XE''' is essential for long-term reliability and performance. Ageing capacitors can cause power instability, video artefacts, audio noise, or even prevent the machine from starting. Proactively replacing these components helps ensure stable operation, protects delicate custom chips, and cures many “mystery” faults common in vintage Atari 8-bit systems.
 
== Visual Inspection & Failure Signs ==
 
Before starting, carefully examine all electrolytic capacitors on the mainboard for:
 
* '''Bulging or domed tops''' – Indicates internal gas pressure and imminent failure.
* '''Leaking electrolyte''' – Brown, green, or white crust around the base or legs.
* '''Corroded or stained PCB areas''' – Suggests past leakage, especially near the power input.
* '''Random resets, video glitches, or audio hum''' – Often traceable to dried-out or high-ESR capacitors.


If any capacitor shows signs of failure, it is strongly recommended to replace '''all''' electrolytic capacitors on the board.
Values and designators come from Atari's own schematics for each 65XE assembly.<ref name="fsm">Atari, ''130XE Personal Computer Field Service Manual'', Section 2: figure 2-7 (Atari 65XE 8 × 4164 assembly CO70025), figure 2-9 (Atari 65XEN 8 × 4164 assembly CA20097) and figure 2-11 (Atari 65XE/800XE 2 × 4464 assembly CA200519, title block C103579-001). Hosted on this wiki: [[:File:Atari 130XE Field Service Manual.pdf]]. Source of every capacitor value and reference designator on this page and of the power connector wiring.</ref> Voltage ratings and Atari part numbers are taken from Atari's parts list for the 130XE board, which uses the same designators and the same part numbers in these positions.<ref name="parts">Atari (U.S.) Corp., ''130XE Parts List'', 25 June 1985. Hosted on this wiki: [[:File:Atari 130XE Parts List and Production Test Instructions.pdf]]. Atari did not publish a separate 65XE parts list in the material hosted here; the ratings below are the ratings Atari gives for the same designators and the same Atari part numbers on the closely related 130XE board, and the schematic values match. Treat the ratings as a minimum, not as a transcription of a 65XE document.</ref>


== Atari 65XE Capacitor List ==
== The supply ==


The 65XE mainboard uses a mix of through-hole and, in later revisions, some SMD electrolytic capacitors. Always cross-check your board’s silkscreen and reference numbers, as minor layout changes exist between European and US models.
Like every XE machine the 65XE takes '''+5 V DC''' from an external brick through a '''7-pin DIN''' (J7) — pins 1, 4 and 6 are +5 V, pins 3, 5 and 7 are ground, pin 2 is the shield.<ref name="fsm" /> There is no rectifier and no regulator on the motherboard; both are inside the brick, which is rated 5 V ±5 % at 1.5 A. See [[Atari 130XE Capacitor Replacement Guide#The supply you are filtering|the 130XE guide]] for the brick's internal schematic and its own capacitors.


=== Mainboard Electrolytic Capacitors ===
== Identify the board ==


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{| class="wikitable styled-table" style="width:100%;"
{| class="wikitable styled-table" style="width:100%; text-align:center;"
|+ Atari 65XE board assemblies
|+'''Atari 65XE Mainboard Electrolytic Capacitors'''
! Assembly !! RAM !! Atari figure !! Notes
! Ref. Designator !! Capacitance !! Voltage !! Function / Location
|-
|-
| C1 || 2200 µF || 16 V || Main +5 V input filter (power smoothing)
| '''CO70025''' || 8 × 4164 (64K × 1) at U9–U16 || 2-7 || The original 65XE board
|-
|-
| C13 || 470 µF || 16 V || +5 V local decoupling (CPU/ASIC area)
| '''CA20097''' || 8 × 4164 at U9–U16 || 2-9 || Labelled "65XEN" by Atari
|-
|-
| C41 || 100 µF || 16 V || Video circuit decoupling
| '''CA200519 / C103579-001''' || 2 × 4464 (64K × 4) at U9 and U10 || 2-11 || Cost-reduced board, shared with the [[Atari 800XE|800XE]]
|-
|}
| C42 || 10 µF || 16 V || Audio output coupling
 
|-
== Capacitor list ==
| C43 || 10 µF || 16 V || Audio input coupling (monitor port)
 
|-
{| class="wikitable styled-table" style="width:95%; text-align:center;"
| C44 || 1 µF || 50 V || Video chroma coupling (monitor port)
|+ Atari 65XE electrolytic capacitors
|-
! Designator(s) !! Value !! Rating !! Type !! Atari part number
| C45 || 10 µF || 16 V || Reset circuit timing
|-
| C46 || 10 µF || 16 V || SIO circuit decoupling
|-
| C47 || 10 µF || 16 V || SIO circuit decoupling
|-
| C48 || 10 µF || 16 V || SIO circuit decoupling
|-
| C49 || 10 µF || 16 V || SIO circuit decoupling
|-
| C50 || 10 µF || 16 V || SIO circuit decoupling
|-
| C51 || 10 µF || 16 V || SIO circuit decoupling
|-
| C52 || 10 µF || 16 V || SIO circuit decoupling
|-
| C53 || 10 µF || 16 V || SIO circuit decoupling
|-
| C54 || 10 µF || 16 V || SIO circuit decoupling
|-
| C55 || 10 µF || 16 V || SIO circuit decoupling
|-
| C56 || 10 µF || 16 V || SIO circuit decoupling
|-
| C57 || 10 µF || 16 V || SIO circuit decoupling
|-
| C58 || 10 µF || 16 V || SIO circuit decoupling
|-
|-
| C59 || 10 µF || 16 V || SIO circuit decoupling
| C1 || 470 µF || 10 V || Aluminium electrolytic, radial || C014368
|-
|-
| C60 || 10 µF || 16 V || SIO circuit decoupling
| C2, C3, C10, C79 || 22 µF || 16 V || Aluminium electrolytic, axial || C014393
|-
|-
| C61 || 10 µF || 16 V || SIO circuit decoupling
| C24, C50, C98 || 10 µF || 16 V || Aluminium electrolytic, radial || C014392
|-
|-
| C62 || 10 µF || 16 V || SIO circuit decoupling
| C19, C20 || 4.7 µF || 35 V || '''Non-polarised''' || C061647
|-
|-
| C63 || 10 µF || 16 V || SIO circuit decoupling
| C22 || 4.7 µF || 35 V || '''Non-polarised''' || C061647
|-
| C64 || 10 µF || 16 V || SIO circuit decoupling
|-
| C65 || 10 µF || 16 V || SIO circuit decoupling
|}
|}


''Note: Some later 65XE boards (especially “Cost Reduced” versions) may use SMD electrolytic capacitors for some of the 10 µF positions. Replace with equivalent SMD or use carefully-fitted radial types.''
'''Ten parts on the CO70025 board; eleven on the CA20097 and CA200519 boards.''' The difference is '''C22''': it is not fitted on the CO70025 assembly, whose schematic footnote reads "C19 and C20 are non polarized", while the CA20097 and CA200519 sheets read "C19, C20, C22 are non polarized".<ref name="fsm" />
 
=== Power Supply (External) ===
 
The 65XE uses an external 5 V DC power supply (“brick”). If you experience unstable voltages or excessive ripple, inspect and recap the PSU as well. Typical values:


{| class="wikitable styled-table" style="width:60%; text-align:center;"
{{Warning|C19, C20 and C22 are '''non-polarised''' (bipolar) electrolytics in the AC-coupled colour and luminance path. Fitting ordinary polarised parts there is a substitution, not a repair.}}
|+'''Atari 65XE Power Supply Capacitors (typical)'''
! Capacitance !! Voltage !! Notes
|-
| 2200 µF || 16 V or 25 V || Main filter (inside PSU brick)
|}


''Always open and service the PSU only if you are experienced with mains voltages.''
Everything else on the board is a ceramic — 1000 pF, 0.01 µF, 0.1 µF, 0.047 µF, or a small NP0 value in picofarads.<ref name="parts" /> There is no 2200 µF part anywhere on any XE board, and no electrolytic above C1's 470 µF.


== Capacitor Replacement Procedure ==
=== Where they are ===


# '''Disassemble:''' Remove the case screws (usually five underneath), then gently lift the top case. Disconnect the keyboard flex cable.
C1 sits directly behind the power switch S1 with C2 and C3 beside it, on the +5 V rail from J7 through L32. C24 and C50 are in the video and audio output stages — C24 at the output of the LM358 (U1), C50 at the CD4050 luminance buffer (U20). C98 is on the +5 V feed at the expansion connector J4B. C19, C20 and C22 are in the colour and luminance summing network around U1.<ref name="fsm" />
# '''Remove the mainboard:''' Unscrew and lift out the PCB, noting the orientation of all connectors.
# '''Desolder old capacitors:''' Use solder wick and/or a pump. Take care not to lift pads, especially on single-sided boards.
# '''Clean pads:''' Remove old flux and any leaked electrolyte using isopropyl alcohol.
# '''Install new capacitors:''' Observe '''polarity''' (long lead = positive; silkscreen usually marks negative). Use low-ESR, 105 °C rated parts.
# '''Trim leads and solder:''' Ensure solid, shiny joints. Avoid excess solder.
# '''Inspect:''' Check for solder bridges and correct orientation.
# '''Reassemble and reconnect:''' Fit the board, connect the keyboard, and close the case.


== Recommended Tools & Parts ==
=== The RF modulator ===


* '''Temperature-controlled soldering iron''' (15–40 W, fine tip)
The modulator A1 is a sealed can and no published source gives a component list for its interior, so there is nothing to recap there. The two board capacitors feeding it, C204 and C205, are 0.1 µF ceramics.<ref name="parts" /> If the RF picture is poor, use the monitor port — it bypasses the modulator entirely.
* '''Desoldering pump and/or braid'''
* '''Isopropyl alcohol (IPA)''' and small brush
* '''Lead-free or leaded 0.5–0.7 mm solder'''
* '''ESR meter''' (optional, for testing old capacitors)
* '''Quality 105 °C, low-ESR capacitors''' (e.g., Nichicon, Panasonic, Rubycon)
* '''Tweezers''' (for SMD parts, if present)
* '''Antistatic wrist strap'''


== Post-Recap Voltage & Ripple Checks ==
== Procedure ==


After recapping, verify the main voltage rails with a multimeter or oscilloscope:
Identical to the [[Atari 130XE Capacitor Replacement Guide#Disassembly|130XE]]: four screws in the bottom cover, disconnect the keyboard and LED connectors, seven screws holding the shielded PCB, seven shield tabs to unbend.<ref name="fsm" /> Use 105 °C parts, bipolar parts for C19, C20 and C22, and a higher voltage rating than the original wherever it is convenient — never a lower one.
 
{| class="wikitable styled-table" style="width:80%; text-align:center;"
|+'''Expected Voltage Rails – Atari 65XE (no cartridge)'''
! Test Point !! Nominal Value !! Acceptable Range !! Max Ripple (p-p)
|-
| +5 V (mainboard input) || 5.00 V || 4.85–5.15 V || < 50 mV
|-
| +5 V (CPU, RAM, ANTIC) || 5.00 V || 4.85–5.15 V || < 50 mV
|-
| Audio out (monitor port) || – || – || No hum/buzz
|}


''If you observe excessive ripple (>100 mV) or unstable voltages, recheck your soldering and consider recapping the external PSU.''
See [[Capacitor Failure Symptoms]], [[Battery Explosion, Capacitor or Corrosion Damage]] and [[Recommended Tools]].


== Additional Tips ==
== Related pages ==
* [[Atari 65XE]]
* [[Atari 65XE General Maintenance]]
* [[Atari 65XE Troubleshooting Guide]]
* [[Atari 130XE Capacitor Replacement Guide]]
* [[Atari 800XE Capacitor Replacement Guide]]


* '''Check the power brick first!''' A faulty PSU can damage new capacitors and chips.
== References ==
* '''Keep capacitor height below 18 mm''' to ensure the metal shield fits.
<references />
* '''Double-check polarity''' before soldering – reversed caps may explode.
* '''Clean any leaked electrolyte''' thoroughly, as it corrodes PCB traces.
* '''Retain original lead spacing''' (usually 5 mm for 10–100 µF, 7.5–10 mm for 2200 µF).
* '''If SMD caps are present,''' use quality SMD replacements or carefully adapt radial types.
* '''Power up with a current-limited supply''' or fuse for first test after recapping.


== Related Pages ==
* [[Atari 65XE Troubleshooting Guide]]
* [[Atari 8-bit Power Supply Maintenance]]
* [[Atari 800XL Capacitor Replacement Guide]]
[[Category:Atari Systems]]
[[Category:Atari Systems]]
[[Category:Capacitor Replacement Guides]]
[[Category:Capacitor Replacement Guides]]
{{Navbox-AtariVintageComputers|state=collapsed}}

Latest revision as of 23:00, 22 September 2026

Atari 65XE mainboard

This is the electrolytic capacitor reference for the Atari 65XE. The 65XE was built on three different board assemblies and the capacitor list is not quite the same on all of them, so identify the board before you order parts.

The full recapping procedure, the power supply description and the verification steps are on the Atari 130XE Capacitor Replacement Guide — they are identical for every XE machine and are not repeated here.

Values and designators come from Atari's own schematics for each 65XE assembly.[1] Voltage ratings and Atari part numbers are taken from Atari's parts list for the 130XE board, which uses the same designators and the same part numbers in these positions.[2]

The supply

[edit | edit source]

Like every XE machine the 65XE takes +5 V DC from an external brick through a 7-pin DIN (J7) — pins 1, 4 and 6 are +5 V, pins 3, 5 and 7 are ground, pin 2 is the shield.[1] There is no rectifier and no regulator on the motherboard; both are inside the brick, which is rated 5 V ±5 % at 1.5 A. See the 130XE guide for the brick's internal schematic and its own capacitors.

Identify the board

[edit | edit source]
Atari 65XE board assemblies
Assembly RAM Atari figure Notes
CO70025 8 × 4164 (64K × 1) at U9–U16 2-7 The original 65XE board
CA20097 8 × 4164 at U9–U16 2-9 Labelled "65XEN" by Atari
CA200519 / C103579-001 2 × 4464 (64K × 4) at U9 and U10 2-11 Cost-reduced board, shared with the 800XE

Capacitor list

[edit | edit source]
Atari 65XE electrolytic capacitors
Designator(s) Value Rating Type Atari part number
C1 470 µF 10 V Aluminium electrolytic, radial C014368
C2, C3, C10, C79 22 µF 16 V Aluminium electrolytic, axial C014393
C24, C50, C98 10 µF 16 V Aluminium electrolytic, radial C014392
C19, C20 4.7 µF 35 V Non-polarised C061647
C22 4.7 µF 35 V Non-polarised C061647

Ten parts on the CO70025 board; eleven on the CA20097 and CA200519 boards. The difference is C22: it is not fitted on the CO70025 assembly, whose schematic footnote reads "C19 and C20 are non polarized", while the CA20097 and CA200519 sheets read "C19, C20, C22 are non polarized".[1]

Everything else on the board is a ceramic — 1000 pF, 0.01 µF, 0.1 µF, 0.047 µF, or a small NP0 value in picofarads.[2] There is no 2200 µF part anywhere on any XE board, and no electrolytic above C1's 470 µF.

Where they are

[edit | edit source]

C1 sits directly behind the power switch S1 with C2 and C3 beside it, on the +5 V rail from J7 through L32. C24 and C50 are in the video and audio output stages — C24 at the output of the LM358 (U1), C50 at the CD4050 luminance buffer (U20). C98 is on the +5 V feed at the expansion connector J4B. C19, C20 and C22 are in the colour and luminance summing network around U1.[1]

The RF modulator

[edit | edit source]

The modulator A1 is a sealed can and no published source gives a component list for its interior, so there is nothing to recap there. The two board capacitors feeding it, C204 and C205, are 0.1 µF ceramics.[2] If the RF picture is poor, use the monitor port — it bypasses the modulator entirely.

Procedure

[edit | edit source]

Identical to the 130XE: four screws in the bottom cover, disconnect the keyboard and LED connectors, seven screws holding the shielded PCB, seven shield tabs to unbend.[1] Use 105 °C parts, bipolar parts for C19, C20 and C22, and a higher voltage rating than the original wherever it is convenient — never a lower one.

See Capacitor Failure Symptoms, Battery Explosion, Capacitor or Corrosion Damage and Recommended Tools.

[edit | edit source]

References

[edit | edit source]
  1. ↑ 1.0 1.1 1.2 1.3 1.4 Atari, 130XE Personal Computer Field Service Manual, Section 2: figure 2-7 (Atari 65XE 8 × 4164 assembly CO70025), figure 2-9 (Atari 65XEN 8 × 4164 assembly CA20097) and figure 2-11 (Atari 65XE/800XE 2 × 4464 assembly CA200519, title block C103579-001). Hosted on this wiki: File:Atari 130XE Field Service Manual.pdf. Source of every capacitor value and reference designator on this page and of the power connector wiring.
  2. ↑ 2.0 2.1 2.2 Atari (U.S.) Corp., 130XE Parts List, 25 June 1985. Hosted on this wiki: File:Atari 130XE Parts List and Production Test Instructions.pdf. Atari did not publish a separate 65XE parts list in the material hosted here; the ratings below are the ratings Atari gives for the same designators and the same Atari part numbers on the closely related 130XE board, and the schematic values match. Treat the ratings as a minimum, not as a transcription of a 65XE document.



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