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Macintosh SE Capacitor Replacement Guide: Difference between revisions

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Verification drive: the 24-row analogue-board table was the Macintosh Plus power/sweep board list and does not apply to the SE at all - the SE uses analogue board 630-0147 plus a SEPARATE power supply module (three variants). Logic board caps were given as 33uF 10V; they are 16V, and the designators were wrong. Removed R56 - the SE has no voltage adjustment. Added Apple FRU numbers, electrical specs, the 2.8V battery threshold, and Pina component-level analogue-board faults from the hosted De...
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{{Unverified data}}
The '''Macintosh SE''' logic board is not one of the Macs that leaks. Its capacitors are the older axial type rather than the surface-mount parts that destroy SE/30, Classic and Classic II boards, and Recap-a-Mac — which has recapped a great many compact Macs — says the SE very rarely needs recapping at all.<ref name="recapse" /> The parts that do need attention are the on-board lithium battery, the analogue board and the power supply.
Replacing electrolytic capacitors (recapping) in your '''Macintosh SE''' is essential for maintaining long-term reliability, consistent power delivery, and clean video output. Aging capacitors can cause instability, poor display quality, or outright system failure. Proactively replacing these components greatly improves the lifespan of your SE.
 
== Safety ==
 
{{Warning|'''The CRT anode holds charge after power-off.''' Discharge it before working inside — see [[CRT Discharge Procedure]].
 
'''The power supply is a separate mains-connected module.''' Depending on which unit is fitted, its primary reservoir is a 620&nbsp;µF 400&nbsp;V capacitor or a series pair of 330&nbsp;µF 200&nbsp;V capacitors.<ref name="c5se" /> Those sit at rectified mains potential and stay charged after the machine is unplugged. Measure across them before touching the primary side. Recapping the supply is a normal repair — just measure first.
 
'''The lithium battery can explode if mishandled.''' Apple's own warning, verbatim: "If handled or discarded improperly, the lithium battery in the Macintosh SE could explode."<ref name="APPLESS" />
 
Apple rates the SE at 90–140&nbsp;V AC or 170–270&nbsp;V AC, 47–63&nbsp;Hz, 100&nbsp;W maximum.<ref name="APPLESS" />}}
 
== Do the Battery First ==
 
The SE keeps PRAM alive with a soldered 1/2&nbsp;AA lithium cell, which Apple describes as a "seven-year lithium battery".<ref name="APPLESS" /> It is now several times that age. Apple's own verification procedure is to remove the logic board, measure across the cell on the 10&nbsp;V DC range, and '''replace it if it reads below 2.8&nbsp;V'''.<ref name="APPLESS" />
 
A leaking cell will take traces with it. See [[Battery Explosion, Capacitor or Corrosion Damage]].


== Capacitor Inspection ==
== Capacitor Inspection ==


Before beginning a recap, check each capacitor for visual signs of failure:
* '''Bulging tops''' — a healthy capacitor has a flat top.
* '''Leaking electrolyte''' — brown or white crust at the leads.
* '''Corrosion or board staining''' near the base of a capacitor.
 
An ESR meter is more use than a capacitance meter here: these parts usually fail by drying out and going high-ESR rather than by losing capacitance. See [[Capacitor Failure Symptoms]].
 
== Logic Board ==


* '''Bulging Tops''' – A domed capacitor top indicates internal gas pressure and failure.
The SE logic board — Apple part '''820-0176''' or '''820-0250''' depending on revision — carries eleven electrolytic capacitors.<ref name="c5se" />
* '''Leaking Electrolyte''' – Brown or white crust near the leads signals electrolyte leakage.
* '''Corrosion or PCB Staining''' – Green residue or darkened board areas mean urgent replacement is needed.


Use a multimeter with ESR testing capabilities if available to confirm health.
<templatestyles src="Template:StyledTable/styles.css" />
{| class="wikitable styled-table" style="width:60%; text-align:center;"
|+ '''Macintosh SE logic board 820-0176 / 820-0250'''
|-
! Reference !! Capacitance !! Voltage
|-
| C4 || 33 µF || 16 V
|-
| C11 || 33 µF || 16 V
|-
| C13 || 33 µF || 16 V
|-
| C16 || 33 µF || 16 V
|-
| C32 || 33 µF || 16 V
|-
| C34 || 33 µF || 16 V
|-
| C36 || 1 µF || 50 V
|-
| C37 || 33 µF || 16 V
|-
| C38 || 33 µF || 16 V
|-
| C62 || 33 µF || 16 V
|-
| C86 || 33 µF || 16 V
|}


== Macintosh SE Capacitor List ==
Two independent sources agree on the totals: Console5 lists the ten 33&nbsp;µF 16&nbsp;V positions and one 1&nbsp;µF 50&nbsp;V position above,<ref name="c5se" /> and Recap-a-Mac's photographic guide, made from a physical SE board, counts exactly '''10&nbsp;×&nbsp;33&nbsp;µF 16&nbsp;V and 1&nbsp;×&nbsp;1&nbsp;µF 50&nbsp;V'''.<ref name="recapse" />


=== Analog Board Capacitors ===
[[File:Macintosh SE Logic Board Capacitors.jpg|thumb|Macintosh SE logic board capacitor locations|center|535x535px]]
The Macintosh SE analog board uses the same layout and component values as the Macintosh Plus, and should be recapped entirely for reliability.
 
== Analogue Board ==
 
'''The SE and SE/30 do not use the Macintosh Plus power/sweep board.''' The Plus combines supply and sweep circuitry on one board; the SE and SE/30 split them, with a separate metal-cased power supply module alongside a much smaller analogue board and a separate video board. Apple's exploded views give the same part numbers for all three modules in both machines: analogue board '''661-0371''', power supply '''661-0370''', video board '''982-0024'''.<ref name="ssse" /><ref name="ssse30" />
 
Thomas Lee puts the relationship precisely: on the SE and SE/30 the horizontal and video circuits are virtually identical to the Plus, but '''the vertical and power supply circuits are completely different'''.<ref name="cmrn" /> A capacitor list taken from a Plus will not match an SE.
 
The bare analogue board is marked '''630-0147'''. Console5 lists twelve electrolytics on it.<ref name="c5147" />


<templatestyles src="Template:StyledTable/styles.css" />
<templatestyles src="Template:StyledTable/styles.css" />
{| class="wikitable styled-table" style="width:80%; text-align:center;"
|+ '''Macintosh SE / SE/30 analogue board 630-0147'''
|-
! Reference !! Capacitance !! Voltage !! Notes
|-
| C2 || 100 µF || 16 V ||
|-
| C7 || 100 µF || 16 V ||
|-
| C9 || 1000 µF || 16 V ||
|-
| C11 || 33 µF || 16 V ||
|-
| C13 || 220 µF || 16 V ||
|-
| C14 || 4700 µF || 16 V ||
|-
| C15 || 3.9 µF || 35 V || '''Bipolar (non-polarised), low ESR.''' See below.
|-
| C18 || 22 µF || 50 V ||
|-
| C19 || 10 µF || 160 V ||
|-
| C22 || 100 µF || 16 V ||
|-
| C24 || 220 µF || 16 V ||
|-
| C25 || 100 µF || 16 V ||
|}
=== C15 is not an ordinary capacitor ===
C15 is the high-frequency, non-polarised capacitor in the '''horizontal''' sweep circuit, and it is the single most commonly failed part on this board. Larry Pina specifies it as 3.9&nbsp;µF NP 25/35&nbsp;V HF and recommends fitting a '''3.9&nbsp;µF NP 100&nbsp;V HF''' part instead, to stop the fault returning.<ref name="dms" /> Console5 likewise flags the position as bipolar, low-ESR.<ref name="c5147" /> Do not fit an ordinary polarised electrolytic here.
Its failure sequence, from Pina:<ref name="dms" />
# Poor horizontal linearity — items on the left wider than items on the right.
# A vertical line on the right of the display a few minutes after startup, with diagonal lines; if left on, the picture darkens and the machine starts to smoke.
# Finally, a bright '''vertical''' line instead of a picture, again with smoke if left powered.
Check the yoke plug '''P1''' at the same time; Pina notes it is often burned by the time C15 has failed.
== Power Supply ==
The power supply is a separate module (Apple '''661-0370'''), and three different units were fitted. Identify yours from the label before ordering anything. Console5 publishes a list for each.<ref name="c5se" />
{| class="wikitable styled-table" style="width:100%; text-align:center;"
{| class="wikitable styled-table" style="width:100%; text-align:center;"
|+ '''Macintosh SE Analog Board Capacitor Specifications'''
|+ '''Power supply: Sony CR-44M'''
|-
! Reference !! Capacitance !! Voltage
|-
| C162 || 620 µF || 400 V
|-
| C164 || 4.7 µF || 350 V
|-
| C165 || 4.7 µF || 350 V
|-
| C168 || 100 µF || 16 V
|-
| C257 || 4700 µF || 16 V
|-
|-
! Label !! Capacitance !! Voltage !! Quantity
| C258 || 6800 µF || 10 V
|-
|-
| C1 || 3.9µF || 35V || 1x
| C259 || 470 µF || 16 V
|-
|-
| C2 || 4700µF || 16V || 1x
| C261 || 2200 µF || 16 V
|-
|-
| C3 || 220µF || 16V || 2x
| C262 || 3300 µF || 10 V
|-
|-
| C5 || 47µF || 10V || 1x
| C263 || 2200 µF || 16 V
|-
|-
| C6 || 22µF || 50V || 2x
| C264 || 470 µF || 16 V
|-
|-
| C10 || 33µF || 16V || 2x
| C265 || 47 µF || 25 V
|-
|-
| C11 || 10µF || 160V || 1x
| C266 || 2200 µF || 16 V
|-
|-
| C12 || 22µF || 50V || 2x
| C269 || 1 µF || 50 V
|-
|-
| C18 || 33µF || 16V || 2x
| C270 || 22 µF || 25 V
|-
|-
| C24 || 2200µF || 16V || 4x
| C275 || 22 µF || 25 V
|-
|-
| C27 || 2200µF || 16V || 1x
| C276 || 22 µF || 25 V
|-
|-
| C28 || 1000µF || 16V || 1x
| C279 || 470 µF || 16 V
|}
 
{| class="wikitable styled-table" style="width:100%; text-align:center;"
|+ '''Power supply: Apple 820-0385-A / Hitachi'''
|-
|-
| C30 || 2200µF || 16V || 1x
! Reference !! Capacitance !! Voltage
|-
|-
| C31 || 220µF || 16V || 1x
| C101 || 10 µF || 25 V
|-
|-
| C32 || 2200µF || 16V || 1x
| C102 || 10 µF || 25 V
|-
|-
| C33 || 4700pF || 250V || 2x
| C206 || 620 µF || 400 V
|-
|-
| C34 || 100µF || 200V || 4x
| C304 || 10 µF || 25 V
|-
|-
| C35 || 100µF || 200V || 1x
| C305 || 1000 µF || 25 V
|-
|-
| C36 || 4700pF || 250V || 1x
| C306 || 470 µF || 16 V
|-
|-
| C37 || 0.47µF || 250V || 1x
| C307 || 1000 µF || 10 V
|-
|-
| C38 || 100µF || 200V || 1x
| C308 || 4700 µF || 10 V
|-
|-
| C39 || 100µF || 200V || 1x
| C309 || 1000 µF || 16 V
|-
|-
| C42 || 470µF || 10V || 2x
| C310 || 1000 µF || 16 V
|-
|-
| C45 || 470µF || 10V || 1x
| C311 || 470 µF || 16 V
|-
| C312 || 470 µF || 16 V
|-
| C401 || 100 µF || 25 V
|-
| C402 || 10 µF || 25 V
|-
| C404 || 22 µF || 16 V
|-
| C408 || 10 µF || 25 V
|-
| C412 || 100 µF || 10 V
|}
|}


=== Logic Board Capacitors ===
The Macintosh SE logic board contains only a few electrolytic capacitors but they are vital to system operation.
<templatestyles src="Template:StyledTable/styles.css" />
{| class="wikitable styled-table" style="width:100%; text-align:center;"
{| class="wikitable styled-table" style="width:100%; text-align:center;"
|+ '''Macintosh SE Logic Board Capacitor Specifications'''
|+ '''Power supply: Apple 699-5047 / ASTEC AA13800'''
|-
! Reference !! Capacitance !! Voltage
|-
| C7 || 330 µF || 200 V
|-
| C8 || 330 µF || 200 V
|-
| C19 || 220 µF || 25 V
|-
| C21 || 47 µF || 63 V
|-
| C23 or C25 || 470 µF || 16 V
|-
| C24 || 1200 µF || 10 V
|-
| C25 or C28 || 220 µF || 16 V
|-
| C31 || 2200 µF || 16 V
|-
|-
! Label !! Capacitance !! Voltage !! Quantity
| C32 || 47 µF || 25 V
|-
|-
| C6 || 1µF || 50V || 1x
| C35 || 470 µF || 16 V
|-
|-
| C1, C3, C4, C5, C7, C8, C9, C10, C12, C13 || 33µF || 10V || 10x
| C36 || 1200 µF || 10 V
|}
|}
[[File:Macintosh SE Logic Board Capacitors.jpg|thumb|Macintosh SE Logic Board Capacitor Locations|center|535x535px]]


> '''Note''': Labeling may differ slightly across board revisions. Double-check values before replacing.
Console5 notes that some — not all — ASTEC supplies were built with three 4700&nbsp;pF metallised-paper RIFA Y-class safety capacitors, and that these should always be replaced when found.<ref name="c5se" /> The ambiguous designators in that last table ("C23 or C25", "C25 or C28") are reproduced as published; check your own board's silkscreen.
 
Note the primary-side ratings: 620&nbsp;µF 400&nbsp;V in the Sony and Hitachi units, and a series pair of 330&nbsp;µF 200&nbsp;V in the ASTEC. Those parts sit at rectified mains potential and hold charge after power-off.
 
=== There is no voltage adjustment ===
 
Apple's Service Source for this machine contains Yoke and Video adjustment procedures and '''nothing else''' — no voltage adjustment, and no rail tolerances.<ref name="APPLESS" /> The adjustable trimmer R56 belongs to the Macintosh 128K/512K/Plus power/sweep board, which is a different board in a different machine;<ref name="cmrn" /> there is no equivalent control here. The video controls on the SE and SE/30 analogue board are brightness, width, height and focus.<ref name="APPLESS" />
 
If the rails are out of specification on one of these machines, the supply module is at fault and needs repair or replacement — there is nothing to turn.


== Capacitor Replacement Procedure ==
== Analogue Board Faults by Component ==
 
Larry Pina's ''The Dead Mac Scrolls'' documents the analogue-board faults of the SE and SE/30 down to individual components, with exact replacement specifications. It is hosted on this wiki.<ref name="dms" />
 
{| class="wikitable styled-table" style="width:100%;"
|-
! Symptom !! Component !! Specification
|-
| No chime, dark display, a dreadful hissing or sizzling noise || '''CR2''' shorted (0.00–0.01&nbsp;Ω) || Barrel rectifier GI854, R-51, 600&nbsp;V 3&nbsp;A. Pina suggests an MR824 (R-51, 400&nbsp;V, 5&nbsp;A) as a heavier-duty replacement.
|-
| No chime, dark display, apparently completely dead, '''no''' hissing noise || '''CR3''' shorted; then '''Q2''' burned; then flyback '''T2''' || CR3 is the same GI854 barrel rectifier. Q2 is the BU4060 horizontal output transistor.
|-
| Right side of the picture shakes in and out during disk access or when a window opens || '''CR2''', then '''Q2''' || As above
|-
| Chimes, fan turns, hard disk spins, but the display stays dark and the brightness control does nothing || '''R22''' open || 470&nbsp;kΩ, ½&nbsp;W, 5&nbsp;%
|-
| Chimes, then a relatively dim '''vertical''' line || '''R19''' burned || 220&nbsp;Ω, ½&nbsp;W, 5&nbsp;%. Vacuum-desolder and resolder linearity coil '''L3''' with fresh solder, or it will recur.
|-
| Poor horizontal linearity, then a bright '''vertical''' line and smoke || '''C15''', and yoke plug '''P1''' || 3.9&nbsp;µF NP 25/35&nbsp;V HF; fit 3.9&nbsp;µF NP 100&nbsp;V HF
|}


# '''Discharge CRT''' – Always discharge the CRT before any internal work to prevent injury.
Two of those deserve emphasis. A '''single vertical line''' is a collapse of the '''horizontal''' sweep and points at C15, R19, L3 or the yoke plug. A '''single horizontal line''' is a collapse of the '''vertical''' sweep — a different circuit, built around the TDA1170 vertical deflection IC that Apple adopted on the compact Macs after the Plus.<ref name="cmrn" /> Either way, switch the machine off immediately: a concentrated line will burn the phosphor in minutes.
# '''Disassemble''' – Remove the case, analog board, and logic board. Label cables if necessary.
# '''Remove Capacitors''' – Desolder cleanly using a pump or braid. Avoid damaging traces.
# '''Install Replacements''' – Observe '''polarity markings'''. Most electrolytics are polarized.
# '''Solder Carefully''' – Apply clean, even solder joints. Trim excess leads.
# '''Inspect & Test''' – Use a multimeter to test continuity and check for accidental shorts.
# '''Power Up Carefully''' – Apply power while monitoring voltages and behavior.


== Recommended Tools ==
== Capacitor Replacement Procedure ==


* '''Temperature-controlled soldering iron (fine tip)'''
# '''Discharge the CRT''' — see [[CRT Discharge Procedure]].
* '''Desoldering pump or braid'''
# '''Remove the battery''' from the logic board before cleaning or reworking it.
* '''Multimeter with continuity/ESR testing'''
# '''Confirm the primary-side capacitors in the power supply are discharged''' before opening it.
* '''Isopropyl alcohol (99%) and antistatic brush'''
# '''Photograph each board''' before removing anything.
* '''Lead-free or leaded 0.5 mm solder'''
# '''Desolder''' with a temperature-controlled iron and wick or a pump.
* '''Protective eyewear and insulated gloves'''
# '''Clean the pads''' and check for corrosion underneath each old part.
# '''Fit the new parts''' the right way round — stripe to negative. '''C15 on the analogue board is non-polarised.'''
# '''Inspect''' under magnification for bridges and cold joints.
# '''Check for shorts''' across each rail before applying power.


== Voltage Adjustment After Recap ==
Tools are listed on [[Recommended Tools]].


After reassembly, verify voltage rails at the floppy drive power plug:
== Module Part Numbers ==


* '''+5V Rail:''' 4.85V – 5.15V
From Apple's exploded view for the Macintosh SE:<ref name="APPLESS" />
* '''+12V Rail:''' 11.9V – 12.7V


Use the analog board trimmer potentiometer ('''R56''') to fine-tune if necessary.
* Analogue board — '''661-0371''' (shared with the SE/30)
* Power supply — '''661-0370''' (shared with the SE/30)
* Video board — '''982-0024''' (shared with the SE/30)
* Logic board — '''661-0530'''
* CRT and yoke assembly — 076-0103
* Chassis — 805-0938


== Additional Tips ==
== Choosing Replacements ==


* Power up the SE at least once every few months to keep capacitors healthy.
* 105&nbsp;°C-rated parts from a known manufacturer for anything in the power supply or on the analogue board.
* Use high-quality brands (e.g., Nichicon, Panasonic, Rubycon).
* Match or exceed the rating printed on the part you removed.
* Double-check polarity before soldering any capacitor.
* Never substitute a polarised part for C15.
* Clean the board of any capacitor residue using alcohol after desoldering.
* Replace metallised-paper (RIFA) safety capacitors on sight.<ref name="c5se" />
* Dispose of old capacitors at an approved electronics waste center.


== Related Pages ==
== Related Pages ==
* [[Macintosh SE]]
* [[Macintosh SE Troubleshooting]]
* [[Macintosh SE Troubleshooting]]
* [[Macintosh SE General Maintenance]]
* [[Macintosh SE General Maintenance]]
* [[Macintosh SE/30 Capacitor Replacement Guide]]
* [[Battery Explosion, Capacitor or Corrosion Damage]]
* [[Capacitor Failure Symptoms]]
* [[CRT Discharge Procedure]]
* [[CRT Discharge Procedure]]
* [[Recommended Tools]]
== References ==
<references>
<ref name="APPLESS">Apple Computer, ''Macintosh SE Service Source'', hosted here as [[:File:Macintosh_SE.pdf]]. Specifications (Electrical, PRAM), Additional Procedures — Battery Verification, Adjustments (Yoke and Video only) and the Exploded View parts list. Apple's Service Source is module-level: it gives procedures, thresholds and field-replaceable-unit numbers, not component values.</ref>
<ref name="ssse">Apple Computer, ''Macintosh SE Service Source'', Exploded View — analogue board 661-0371, power supply 661-0370, video board 982-0024. [[:File:Macintosh_SE.pdf]]</ref>
<ref name="ssse30">Apple Computer, ''Macintosh SE/30 Service Source'', Exploded View — the same three module part numbers. [[:File:Macintosh SE30.pdf]]</ref>
<ref name="c5se">Console5 TechWiki, "Macintosh SE" — logic board 820-0176 / 820-0250, analogue board 630-0147, and the three power supply variants (Sony CR-44M, Apple 820-0385-A / Hitachi, Apple 699-5047 / ASTEC AA13800). https://wiki.console5.com/wiki/Macintosh_SE Secondary source — vendor cap-kit lists, not Apple documentation.</ref>
<ref name="c5147">Console5 TechWiki, "Mac Analog Board: 630-0147". https://wiki.console5.com/wiki/Mac_Analog_Board:_630-0147 Secondary source.</ref>
<ref name="recapse">Bruce / Recap-a-Mac, "Macintosh SE". https://recapamac.com.au/macintosh-se/ Logic board capacitor count from a photographic recapping guide, and the observation that the SE's axial electrolytics are not prone to the leakage seen in later surface-mount Macs. Secondary source.</ref>
<ref name="dms">Larry Pina, ''The Dead Mac Scrolls'' (1992), hosted here as [[:File:The Dead Mac Scrolls 1992.pdf]], "Mac SE and SE/30" section. Symptom-to-component diagnoses with exact part specifications.</ref>
<ref name="cmrn">Thomas H. Lee, ''Classic Mac Repair Notes'', revision of 31 May 2007 (©2000 Thomas H. Lee, all rights reserved; not re-hosted here for that reason). https://archive.org/details/Classic_Mac_Repair_Notes Section 1.0 on which circuits the SE and SE/30 share with the Plus, and section 7.3 on the TDA1170 vertical deflection IC used in the compact Macs after the Plus.</ref>
</references>


[[Category:Apple Vintage Computers]]
[[Category:Apple Vintage Computers]]
[[Category: Capacitor Replacement Guides]]
[[Category:Capacitor Replacement Guides]]

Revision as of 00:13, 23 September 2026

The Macintosh SE logic board is not one of the Macs that leaks. Its capacitors are the older axial type rather than the surface-mount parts that destroy SE/30, Classic and Classic II boards, and Recap-a-Mac — which has recapped a great many compact Macs — says the SE very rarely needs recapping at all.[1] The parts that do need attention are the on-board lithium battery, the analogue board and the power supply.

Safety

Do the Battery First

The SE keeps PRAM alive with a soldered 1/2 AA lithium cell, which Apple describes as a "seven-year lithium battery".[3] It is now several times that age. Apple's own verification procedure is to remove the logic board, measure across the cell on the 10 V DC range, and replace it if it reads below 2.8 V.[3]

A leaking cell will take traces with it. See Battery Explosion, Capacitor or Corrosion Damage.

Capacitor Inspection

  • Bulging tops — a healthy capacitor has a flat top.
  • Leaking electrolyte — brown or white crust at the leads.
  • Corrosion or board staining near the base of a capacitor.

An ESR meter is more use than a capacitance meter here: these parts usually fail by drying out and going high-ESR rather than by losing capacitance. See Capacitor Failure Symptoms.

Logic Board

The SE logic board — Apple part 820-0176 or 820-0250 depending on revision — carries eleven electrolytic capacitors.[2]

Macintosh SE logic board 820-0176 / 820-0250
Reference Capacitance Voltage
C4 33 µF 16 V
C11 33 µF 16 V
C13 33 µF 16 V
C16 33 µF 16 V
C32 33 µF 16 V
C34 33 µF 16 V
C36 1 µF 50 V
C37 33 µF 16 V
C38 33 µF 16 V
C62 33 µF 16 V
C86 33 µF 16 V

Two independent sources agree on the totals: Console5 lists the ten 33 µF 16 V positions and one 1 µF 50 V position above,[2] and Recap-a-Mac's photographic guide, made from a physical SE board, counts exactly 10 × 33 µF 16 V and 1 × 1 µF 50 V.[1]

Macintosh SE logic board capacitor locations

Analogue Board

The SE and SE/30 do not use the Macintosh Plus power/sweep board. The Plus combines supply and sweep circuitry on one board; the SE and SE/30 split them, with a separate metal-cased power supply module alongside a much smaller analogue board and a separate video board. Apple's exploded views give the same part numbers for all three modules in both machines: analogue board 661-0371, power supply 661-0370, video board 982-0024.[4][5]

Thomas Lee puts the relationship precisely: on the SE and SE/30 the horizontal and video circuits are virtually identical to the Plus, but the vertical and power supply circuits are completely different.[6] A capacitor list taken from a Plus will not match an SE.

The bare analogue board is marked 630-0147. Console5 lists twelve electrolytics on it.[7]

Macintosh SE / SE/30 analogue board 630-0147
Reference Capacitance Voltage Notes
C2 100 µF 16 V
C7 100 µF 16 V
C9 1000 µF 16 V
C11 33 µF 16 V
C13 220 µF 16 V
C14 4700 µF 16 V
C15 3.9 µF 35 V Bipolar (non-polarised), low ESR. See below.
C18 22 µF 50 V
C19 10 µF 160 V
C22 100 µF 16 V
C24 220 µF 16 V
C25 100 µF 16 V

C15 is not an ordinary capacitor

C15 is the high-frequency, non-polarised capacitor in the horizontal sweep circuit, and it is the single most commonly failed part on this board. Larry Pina specifies it as 3.9 µF NP 25/35 V HF and recommends fitting a 3.9 µF NP 100 V HF part instead, to stop the fault returning.[8] Console5 likewise flags the position as bipolar, low-ESR.[7] Do not fit an ordinary polarised electrolytic here.

Its failure sequence, from Pina:[8]

  1. Poor horizontal linearity — items on the left wider than items on the right.
  2. A vertical line on the right of the display a few minutes after startup, with diagonal lines; if left on, the picture darkens and the machine starts to smoke.
  3. Finally, a bright vertical line instead of a picture, again with smoke if left powered.

Check the yoke plug P1 at the same time; Pina notes it is often burned by the time C15 has failed.

Power Supply

The power supply is a separate module (Apple 661-0370), and three different units were fitted. Identify yours from the label before ordering anything. Console5 publishes a list for each.[2]

Power supply: Sony CR-44M
Reference Capacitance Voltage
C162 620 µF 400 V
C164 4.7 µF 350 V
C165 4.7 µF 350 V
C168 100 µF 16 V
C257 4700 µF 16 V
C258 6800 µF 10 V
C259 470 µF 16 V
C261 2200 µF 16 V
C262 3300 µF 10 V
C263 2200 µF 16 V
C264 470 µF 16 V
C265 47 µF 25 V
C266 2200 µF 16 V
C269 1 µF 50 V
C270 22 µF 25 V
C275 22 µF 25 V
C276 22 µF 25 V
C279 470 µF 16 V
Power supply: Apple 820-0385-A / Hitachi
Reference Capacitance Voltage
C101 10 µF 25 V
C102 10 µF 25 V
C206 620 µF 400 V
C304 10 µF 25 V
C305 1000 µF 25 V
C306 470 µF 16 V
C307 1000 µF 10 V
C308 4700 µF 10 V
C309 1000 µF 16 V
C310 1000 µF 16 V
C311 470 µF 16 V
C312 470 µF 16 V
C401 100 µF 25 V
C402 10 µF 25 V
C404 22 µF 16 V
C408 10 µF 25 V
C412 100 µF 10 V
Power supply: Apple 699-5047 / ASTEC AA13800
Reference Capacitance Voltage
C7 330 µF 200 V
C8 330 µF 200 V
C19 220 µF 25 V
C21 47 µF 63 V
C23 or C25 470 µF 16 V
C24 1200 µF 10 V
C25 or C28 220 µF 16 V
C31 2200 µF 16 V
C32 47 µF 25 V
C35 470 µF 16 V
C36 1200 µF 10 V

Console5 notes that some — not all — ASTEC supplies were built with three 4700 pF metallised-paper RIFA Y-class safety capacitors, and that these should always be replaced when found.[2] The ambiguous designators in that last table ("C23 or C25", "C25 or C28") are reproduced as published; check your own board's silkscreen.

Note the primary-side ratings: 620 µF 400 V in the Sony and Hitachi units, and a series pair of 330 µF 200 V in the ASTEC. Those parts sit at rectified mains potential and hold charge after power-off.

There is no voltage adjustment

Apple's Service Source for this machine contains Yoke and Video adjustment procedures and nothing else — no voltage adjustment, and no rail tolerances.[3] The adjustable trimmer R56 belongs to the Macintosh 128K/512K/Plus power/sweep board, which is a different board in a different machine;[6] there is no equivalent control here. The video controls on the SE and SE/30 analogue board are brightness, width, height and focus.[3]

If the rails are out of specification on one of these machines, the supply module is at fault and needs repair or replacement — there is nothing to turn.

Analogue Board Faults by Component

Larry Pina's The Dead Mac Scrolls documents the analogue-board faults of the SE and SE/30 down to individual components, with exact replacement specifications. It is hosted on this wiki.[8]

Symptom Component Specification
No chime, dark display, a dreadful hissing or sizzling noise CR2 shorted (0.00–0.01 Ω) Barrel rectifier GI854, R-51, 600 V 3 A. Pina suggests an MR824 (R-51, 400 V, 5 A) as a heavier-duty replacement.
No chime, dark display, apparently completely dead, no hissing noise CR3 shorted; then Q2 burned; then flyback T2 CR3 is the same GI854 barrel rectifier. Q2 is the BU4060 horizontal output transistor.
Right side of the picture shakes in and out during disk access or when a window opens CR2, then Q2 As above
Chimes, fan turns, hard disk spins, but the display stays dark and the brightness control does nothing R22 open 470 kΩ, ½ W, 5 %
Chimes, then a relatively dim vertical line R19 burned 220 Ω, ½ W, 5 %. Vacuum-desolder and resolder linearity coil L3 with fresh solder, or it will recur.
Poor horizontal linearity, then a bright vertical line and smoke C15, and yoke plug P1 3.9 µF NP 25/35 V HF; fit 3.9 µF NP 100 V HF

Two of those deserve emphasis. A single vertical line is a collapse of the horizontal sweep and points at C15, R19, L3 or the yoke plug. A single horizontal line is a collapse of the vertical sweep — a different circuit, built around the TDA1170 vertical deflection IC that Apple adopted on the compact Macs after the Plus.[6] Either way, switch the machine off immediately: a concentrated line will burn the phosphor in minutes.

Capacitor Replacement Procedure

  1. Discharge the CRT — see CRT Discharge Procedure.
  2. Remove the battery from the logic board before cleaning or reworking it.
  3. Confirm the primary-side capacitors in the power supply are discharged before opening it.
  4. Photograph each board before removing anything.
  5. Desolder with a temperature-controlled iron and wick or a pump.
  6. Clean the pads and check for corrosion underneath each old part.
  7. Fit the new parts the right way round — stripe to negative. C15 on the analogue board is non-polarised.
  8. Inspect under magnification for bridges and cold joints.
  9. Check for shorts across each rail before applying power.

Tools are listed on Recommended Tools.

Module Part Numbers

From Apple's exploded view for the Macintosh SE:[3]

  • Analogue board — 661-0371 (shared with the SE/30)
  • Power supply — 661-0370 (shared with the SE/30)
  • Video board — 982-0024 (shared with the SE/30)
  • Logic board — 661-0530
  • CRT and yoke assembly — 076-0103
  • Chassis — 805-0938

Choosing Replacements

  • 105 °C-rated parts from a known manufacturer for anything in the power supply or on the analogue board.
  • Match or exceed the rating printed on the part you removed.
  • Never substitute a polarised part for C15.
  • Replace metallised-paper (RIFA) safety capacitors on sight.[2]

References

  1. ↑ 1.0 1.1 Bruce / Recap-a-Mac, "Macintosh SE". https://recapamac.com.au/macintosh-se/ Logic board capacitor count from a photographic recapping guide, and the observation that the SE's axial electrolytics are not prone to the leakage seen in later surface-mount Macs. Secondary source.
  2. ↑ 2.0 2.1 2.2 2.3 2.4 2.5 Console5 TechWiki, "Macintosh SE" — logic board 820-0176 / 820-0250, analogue board 630-0147, and the three power supply variants (Sony CR-44M, Apple 820-0385-A / Hitachi, Apple 699-5047 / ASTEC AA13800). https://wiki.console5.com/wiki/Macintosh_SE Secondary source — vendor cap-kit lists, not Apple documentation.
  3. ↑ 3.0 3.1 3.2 3.3 3.4 3.5 3.6 Apple Computer, Macintosh SE Service Source, hosted here as File:Macintosh_SE.pdf. Specifications (Electrical, PRAM), Additional Procedures — Battery Verification, Adjustments (Yoke and Video only) and the Exploded View parts list. Apple's Service Source is module-level: it gives procedures, thresholds and field-replaceable-unit numbers, not component values.
  4. ↑ Apple Computer, Macintosh SE Service Source, Exploded View — analogue board 661-0371, power supply 661-0370, video board 982-0024. File:Macintosh_SE.pdf
  5. ↑ Apple Computer, Macintosh SE/30 Service Source, Exploded View — the same three module part numbers. File:Macintosh SE30.pdf
  6. ↑ 6.0 6.1 6.2 Thomas H. Lee, Classic Mac Repair Notes, revision of 31 May 2007 (©2000 Thomas H. Lee, all rights reserved; not re-hosted here for that reason). https://archive.org/details/Classic_Mac_Repair_Notes Section 1.0 on which circuits the SE and SE/30 share with the Plus, and section 7.3 on the TDA1170 vertical deflection IC used in the compact Macs after the Plus.
  7. ↑ 7.0 7.1 Console5 TechWiki, "Mac Analog Board: 630-0147". https://wiki.console5.com/wiki/Mac_Analog_Board:_630-0147 Secondary source.
  8. ↑ 8.0 8.1 8.2 Larry Pina, The Dead Mac Scrolls (1992), hosted here as File:The Dead Mac Scrolls 1992.pdf, "Mac SE and SE/30" section. Symptom-to-component diagnoses with exact part specifications.
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