Editing Macintosh SE Capacitor Replacement Guide

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.

== 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 ==

* '''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.<ref name="c5se" />

<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
|}

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" />

[[File:Macintosh SE Logic Board Capacitors.jpg|thumb|Macintosh SE logic board capacitor locations|center|535x535px]]

== 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" />
{| 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;"
|+ '''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
|}

{| class="wikitable styled-table" style="width:100%; text-align:center;"
|+ '''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
|}

{| class="wikitable styled-table" style="width:100%; text-align:center;"
|+ '''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&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.

== 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
|}

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.

== Capacitor Replacement Procedure ==

# '''Discharge the CRT''' — see [[CRT Discharge Procedure]].
# '''Remove the battery''' from the logic board before cleaning or reworking it.
# '''Confirm the primary-side capacitors in the power supply are discharged''' before opening it.
# '''Photograph each board''' before removing anything.
# '''Desolder''' with a temperature-controlled iron and wick or a pump.
# '''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.

Tools are listed on [[Recommended Tools]].

== Module Part Numbers ==

From Apple's exploded view for the Macintosh SE:<ref name="APPLESS" />

* 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&nbsp;°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.<ref name="c5se" />

== Related Pages ==
* [[Macintosh SE]]
* [[Macintosh SE Troubleshooting]]
* [[Macintosh SE General Maintenance]]
* [[Macintosh SE/30 Capacitor Replacement Guide]]
* [[Battery Explosion, Capacitor or Corrosion Damage]]
* [[Capacitor Failure Symptoms]]
* [[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:Capacitor Replacement Guides]]