Editing Macintosh SE/30 Capacitor Replacement Guide

Every '''Macintosh SE/30''' has leaking capacitors. Not most — all of them. The surface-mount electrolytics on the logic board vent a conductive, corrosive electrolyte that creeps under adjacent ICs and eats traces and vias, and the longer a board is left the greater the chance the damage goes beyond what a recap will fix.<ref name="recapse30" /> This is the single most important fact about the machine, and it is why the logic board comes first on this page and the analogue board second.

== Safety ==

{{Warning|'''The logic board can be recapped without touching the CRT.''' It lifts out of the chassis once the cover is off. You do not need to discharge the CRT to recap it — but you do need to discharge the CRT before working on the analogue board, the video board, the anode lead or the CRT socket board. See [[CRT Discharge Procedure]].

'''The power supply is a separate mains-connected module.''' Its primary reservoir is a 620&nbsp;µF 400&nbsp;V capacitor or a series pair of 330&nbsp;µF 200&nbsp;V capacitors depending on which unit is fitted.<ref name="c5se" /> Those sit at rectified mains potential and stay charged after power-off. Measure across them before touching the primary side.

'''The lithium battery can explode if mishandled.''' Apple's warning is explicit: "If handled or discarded improperly, the lithium battery in the Macintosh SE/30 could explode."<ref name="APPLESS" />

Apple rates the SE/30 at 120–240&nbsp;V AC, automatically configured, 48–62&nbsp;Hz, 75&nbsp;W maximum.<ref name="APPLESS" />}}

== Do the Battery First ==

Remove or check the 1/2&nbsp;AA lithium PRAM cell before anything else. Apple's 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 leaked cell produces exactly the same kind of trace damage as a leaked capacitor, in the same part of the board. See [[Battery Explosion, Capacitor or Corrosion Damage]].

== Capacitor Inspection ==

On an SE/30 the question is not whether the capacitors have leaked but how far the electrolyte has travelled.

* '''Dark haloes or dried crust''' around the base of the surface-mount cans.
* '''Dull, grey or green solder joints''' on nearby IC pins — electrolyte attacks the joint before it attacks the trace.
* '''Missing or thinned traces''' near the capacitors, best seen under a loupe with light across the board.
* Bulging tops are '''not''' a reliable sign on these parts; they usually leak from the base without deforming.

See [[Capacitor Failure Symptoms]].

== Logic Board ==

The SE/30 logic board, Apple part '''820-0260''', carries thirteen electrolytic capacitors: eleven surface-mount parts and two axials.<ref name="c5se" />

<templatestyles src="Template:StyledTable/styles.css" />
{| class="wikitable styled-table" style="width:75%; text-align:center;"
|+ '''Macintosh SE/30 logic board 820-0260'''
|-
! Reference !! Capacitance !! Voltage !! Type
|-
| C1 || 47 µF || 16 V || SMD
|-
| C2 || 470 µF || 16 V || Axial
|-
| C3 || 47 µF || 16 V || SMD
|-
| C4 || 47 µF || 16 V || SMD
|-
| C5 || 47 µF || 16 V || SMD
|-
| C6 || 1 µF || 50 V || SMD
|-
| C7 || 47 µF || 16 V || SMD
|-
| C8 || 47 µF || 16 V || SMD
|-
| C9 || 47 µF || 16 V || SMD
|-
| C10 || 47 µF || 16 V || SMD
|-
| C11 || 220 µF || 16 V || Axial
|-
| C12 || 47 µF || 16 V || SMD
|-
| C13 || 47 µF || 16 V || SMD
|}

Two independent sources agree. Console5 gives the designators above;<ref name="c5se" /> Recap-a-Mac's photographic guide, made from physical boards, counts '''10&nbsp;×&nbsp;47&nbsp;µF 16&nbsp;V, 1&nbsp;×&nbsp;1&nbsp;µF 50&nbsp;V, 1&nbsp;×&nbsp;220&nbsp;µF 16&nbsp;V and 1&nbsp;×&nbsp;470&nbsp;µF 16&nbsp;V'''.<ref name="recapse30" /> The two axials are easy to overlook — they are ordinary through-hole parts, not the leaky surface-mount cans, but they are on the list.

[[File:Macintosh SE30 Logic Board Capacitors.jpg|thumb|Macintosh SE/30 logic board capacitor locations|center|587x587px]]

=== Board revisions ===

Recap-a-Mac notes a layout difference worth knowing before you follow a photograph: earlier boards have a '''socketed''' 68030; later boards have a '''dark grey soldered''' CPU, and on those the 47&nbsp;µF 16&nbsp;V capacitor near the ROM slot sits '''above''' the slot rather than below it.<ref name="recapse30" />

=== Where the damage goes ===

Two areas take the brunt, both flagged by Recap-a-Mac from repeated repairs:<ref name="recapse30" />

* '''The video multiplexer circuit''' — the row of Ux8 ICs below the large axial capacitor. Look closely for damaged traces and dried electrolyte around those pins. Faults here are common.
* '''The RAM multiplexers''' — the ICs marked "F258" above the ROM slot. If you are getting Sad Mac chimes with known-good RAM, suspect one of these rather than the memory. See [[Sad Mac Error Codes]].

Trace continuity around every capacitor should be checked with a meter before the board is powered again; a recap that leaves a broken via behind produces a machine that still does not work and a repairer who concludes, wrongly, that the recap failed.

=== Replacement parts ===

Recap-a-Mac's own choices for this board:<ref name="recapse30" />

* 1&nbsp;µF 50&nbsp;V — KEMET T491B105K050AT tantalum
* 47&nbsp;µF 16&nbsp;V — KEMET T491D476K016AT tantalum
* 220&nbsp;µF 16&nbsp;V axial — Vishay MAL213825221E3
* 470&nbsp;µF 16&nbsp;V axial — Vishay MAL211835471E3

Solid tantalum and solid polymer parts have no liquid electrolyte and cannot leak. Tantalum fails short; polymer usually fails open, which is gentler on whatever is downstream. Either is a reasonable choice here provided the voltage rating is comfortably above the rail.

== 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
|}

A '''single vertical line''' is a horizontal sweep collapse — C15, R19, L3 or the yoke plug. A '''single horizontal line''' is a vertical sweep collapse, a different circuit built around the TDA1170 vertical deflection IC.<ref name="cmrn" /> In either case switch off at once; a concentrated line burns the phosphor within minutes.

== Capacitor Replacement Procedure ==

# '''Remove the logic board''' and take the battery off it.
# '''Remove the old surface-mount capacitors.''' Alternate heat between the two terminals while gently tilting the can, or use hot air with the surrounding plastic shielded. Twisting a can off cold will take the pads with it.
# '''Clean thoroughly.''' Isopropyl alcohol and a soft brush over the whole area, repeatedly, until no residue transfers to a clean swab.
# '''Inspect and test.''' Check continuity across every trace that ran under or beside a capacitor. Repair breaks with fine wire before fitting anything new.
# '''Fit the new parts''' the right way round. On a tantalum the stripe marks '''positive'''; on an aluminium electrolytic it marks '''negative'''. This catches people out.
# '''Check for shorts''' across each rail before applying power.
# '''Discharge the CRT''' before starting on the analogue board, if you are going that far.

Tools are listed on [[Recommended Tools]].

== Module Part Numbers ==

From Apple's exploded view for the Macintosh SE/30:<ref name="APPLESS" />

* Analogue board — '''661-0371''' (shared with the SE)
* Power supply — '''661-0370''' (shared with the SE)
* Video board — '''982-0024''' (shared with the SE)
* Logic board — '''661-0527'''
* CRT and yoke assembly — 076-0103
* Front bezel — 630-5499

== Related Pages ==
* [[Macintosh SE/30]]
* [[Macintosh SE/30 General Maintenance]]
* [[Macintosh SE/30 Troubleshooting]]
* [[Macintosh SE Capacitor Replacement Guide]]
* [[Battery Explosion, Capacitor or Corrosion Damage]]
* [[Capacitor Failure Symptoms]]
* [[CRT Discharge Procedure]]
* [[Recommended Tools]]
* [[Sad Mac Error Codes]]

== References ==
<references>
<ref name="APPLESS">Apple Computer, ''Macintosh SE/30 Service Source'', hosted here as [[:File:Macintosh SE30.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: 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" (the SE/30 redirects here) — SE/30 logic board 820-0260, analogue board 630-0147 and the three power supply variants. 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="recapse30">Bruce / Recap-a-Mac, "Macintosh SE/30". https://recapamac.com.au/macintosh-se-30/ Capacitor counts and replacement part numbers from a photographic recapping guide; the socketed-versus-soldered CPU revision difference; the Ux8 video multiplexer and F258 RAM multiplexer failures. Secondary source, derived from recapping these machines in practice.</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.</ref>
</references>

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