Recap guide

Recap the Apple IIGS power supply

The IIGS supply uses yellow canister electrolytics, two large black electrolytics and .22 uF safety caps that age and fail.

Open the interactive checklist Tick off each capacitor as you replace it. It saves in your browser.

Worth a recap. Reports say it is a common and useful fix on this machine.

Which board do I have?

Boards changed during production. These notes come from the linked sources, and many are only partly documented, so check the board in front of you.

• IIgs Astec supply (Low confidence). How to tell: Gold cased. Capacitors: 1000uF 10V electrolytics, 0.22uF safety caps, 5 yellow and 2 black cans. Capacitor list differs from other revisions: not known. Source
• IIgs Dynacomp supply (Low confidence). How to tell: Bare aluminum case. Capacitors: No list. Capacitor list differs from other revisions: not known. Source

Where to start

Clues from write-ups and forum threads, not a diagnosis. Low confidence means one thread or one repair; high means several write-ups agree.

• Parts to replace (Medium confidence). One thread names five yellow canister electrolytics, two large black electrolytics and two silver .22 uF safety caps, gives a couple of values and recommends a kit. There is no full list. Source
• Safety caps (Medium confidence). Apple II family advice favors swapping RIFA-type safety caps, and notes the IIc+ Sony supply has none. Source

Tips, tales and maybes

Found in write-ups and forum threads. These are other people's reports, not tested by us. Check part references and values against your own board.

• Story: Earth leakage breaker trips (Low confidence). An owner whose IIGS kept tripping the earth leakage breaker recapped the Astec AA13591 supply and posted a cap map, but only as image attachments, so values are not in the page text. Source
• Watch out: Transparent-epoxy film caps and X versus Y class (Medium confidence). A thread says RIFA and WIMA MP3 style film caps in clear epoxy can crack, take on moisture and conduct, and may explode, so replace them with opaque-epoxy parts. It stresses identifying whether each safety cap is an X or a Y class position and fitting the matching class. Source
• Tip: Load-test the supply and check the small stuff (Low confidence). A poster says IIGS supplies need a load, such as a drive or resistor with a meter, to judge the rails, and that dead ones often have an open 100k resistor or tired electrolytics near the AC input. Dark gold safety caps were called almost always bad and a failed one sprays burning goo. Source
• Story: Three RIFAs popped (Low confidence). A poster whose supply had already popped three RIFA caps ordered 0.22uF 250V film replacements. A reply recommended replacing the known RIFA problem parts rather than recapping everything. Source

Before you start

• Boards changed during production. Check your board number against the guides before you order parts.
• A mains power supply can hold a dangerous charge. If you are not trained to work on one, have a professional do it.

Manuals and technical documents

Service manuals, schematics and datasheets for this machine, kept in our own library. Check your own board and part numbers against them.

• Apple IIgs Technical Procedures - June, 1987 (Service manual)

All 1 documents for Apple IIGS power supply in the library

Guides we used

This page and the interactive bench are built from these. They have the photos and the full detail, so please read them and support their authors.

• IIGS replacement capacitor (Forum) by Applefritter forum. Names which parts to replace (with a couple of values) and recommends a kit; no full list
• Apple II and IIe power supply RIFA replacements (Forum) by Applefritter forum. Has a capacitor list. General Apple II family safety-cap advice; also mentions the IIc+ Sony supply has no RIFA caps

Apple IIgs motherboard 607-0170-A / 607-0173-D (ROM 1)

Twenty capacitors, mostly 22 uF 16 V. The two 1000 uF parts at C6 and C61 are the big ones.

Apple IIgs motherboard 607-0275-03 (ROM 3)

Twenty-two capacitors. It is the ROM 1 list plus C62 and a 470 uF at SC50.

Astec AA13581 power supply, 120 V

Console5 says Astec changed values a lot during production and that many are not critical, so small differences up or down are fine. This is Variant 1 of four. The variants differ at C4 (220 uF on variant 4), C12 (470 uF 10 V, 220 uF 16 V or 220 uF 16 V), C13 (220 uF 16 V, 470 uF 10 V or 270 uF 10 V), C15 (1200 uF on the others) and C20 (470 uF 16 V on variant 2). Its kits use the largest value found. C2 is a separate 0.01 uF 250 V Y-type safety part. Mains power supply: unplug it and let it discharge first.

Astec AA13581 power supply, 240 V

Mains power supply: unplug it and let it discharge first. Console5's kits fit 270 uF at C12 and a 16 V part at C13.

Dyna Comp LR38879 power supply

Console5 lists this by value and count, in order from the mains input to the output, since the board has no reference numbers. It also says some LR38 supplies have the LR62786 parts instead: look for five 1000 uF capacitors against three. It also warns that metallized paper RIFA or WIMA safety capacitors (0.22 uF, 0.1 uF or 4700 pF) may be fitted and should always be replaced. Mains power supply: unplug it and let it discharge first.

Dyna Comp LR62786 power supply

Listed by value and count, in order from the mains input to the output. Mains power supply: unplug it and let it discharge first.

Dyna Comp LR90974 power supply

Listed by value and count, in order from the mains input to the output. Console5 says some revisions have a film capacitor toward the middle of the board and some have a second 1 uF part. Mains power supply: unplug it and let it discharge first.

Shopping list

104 capacitors in all, grouped by value. Buy a few spares.

• 32 x 22 µF, 16 V (check your board): Amazon · eBay
• 14 x 1000 µF, 10 V (check your board): Amazon · eBay
• 9 x 10 µF, 25 V (check your board): Amazon · eBay
• 8 x 1 µF, 50 V (check your board): Amazon · eBay
• 7 x 1000 µF, 16 V (check your board): Amazon · eBay
• 6 x 100 µF, 200 V (check your board): Amazon · eBay
• 4 x 330 µF, 25 V (check your board): Amazon · eBay
• 4 x 330 µF, 35 V (check your board): Amazon · eBay
• 3 x 220 µF, 10 V (check your board): Amazon · eBay
• 3 x 470 µF, 16 V (check your board): Amazon · eBay
• 2 x 1 µF, 35 V (check your board): Amazon · eBay
• 2 x 270 µF, 16 V (check your board): Amazon · eBay
• 2 x 330 µF, 16 V (check your board): Amazon · eBay
• 2 x 2200 µF, 16 V (check your board): Amazon · eBay
• 1 x 10 µF, 50 V (check your board): Amazon · eBay
• 1 x 100 µF, 16 V (check your board): Amazon · eBay
• 1 x 100 µF, 400 V (check your board): Amazon · eBay
• 1 x 330 µF, 200 V (check your board): Amazon · eBay
• 1 x 1000 µF, 6.3 V (check your board): Amazon · eBay
• 1 x 1200 µF, 16 V (check your board): Amazon · eBay

Console5 capacitor kits for this machine

Console5 sells ready-made capacitor kits. Kits come in different versions, so match the board number in the kit name to yours and check the listing before you buy.

• Apple 2GS Main PCB Cap Kit All Versions Iigs
• Apple 2GS 699 0126 Astec AA13581 Power Supply Cap Kit
• Apple 2GS 699 0126 Dynacomp Power Supply Cap Kit
• Apple 2GS Astec AA13591 240V Power Supply Cap Kit

Skip the sourcing

• Ready-made kit: Amazon · eBay
• Already recapped: Amazon · eBay

While you are in there

• Need the machine itself?: Amazon · eBay
• A box of spare capacitors: Amazon · eBay

Affiliate links. As an Amazon Associate I earn from qualifying purchases. These links only search by name. Disclosure

Step by step

1. Photograph both sides of the board before you touch anything. Zoom in on every capacitor. The photo is your map when you are three hours in.
2. Unplug it, take out the batteries and let it sit. Old power supplies and CRT parts can hold a charge. If your machine has a tube, leave the tube and its board to a professional.
3. Open it up and keep the screws sorted. A muffin tin or an egg carton works. Different screws go in different holes, and the holes never forgive you.
4. Look for leaks. Clean any sticky residue off with isopropyl alcohol and a soft brush. A leaked capacitor leaves brown crust and can eat copper traces. Look at the traces under it, not only the part itself.
5. Mark the polarity of every capacitor on the photo before it comes off. On an electrolytic, the stripe marks the negative leg. The board usually shows a half-shaded circle or a bar for the same spot.
6. Remove the old capacitors one at a time. Surface mount: add fresh solder to both ends and rock the part off, or use flux and a low-melt alloy. Through-hole: heat one leg at a time and clear the hole with wick or a pump.
7. Clean the pads and check for lifted pads or damaged traces. Clean flux off with isopropyl. A bad pad needs a jumper wire, not hope.
8. Fit and solder the new capacitor, matching polarity. Same capacity, same or higher voltage, and it has to physically fit. Work from the smallest parts up.
9. Clean the flux off and look at every joint. A good joint is shiny and shaped like a tiny volcano. A dull blob or a ball is a cold joint: reflow it.
10. With a multimeter, check for shorts across the power rails before you power it on. Use the continuity or resistance setting. A reading near zero means stop and look for a solder bridge.
11. Power it up and test everything: video, sound, controls, the lot. If something is wrong, check polarity first. It is the most common mistake and the easiest fix.

Tools

• Temperature-controlled soldering station. Steady heat so you do not cook pads. Most recaps are done between 320 and 350 C. Top: Hakko FX-951 · Mid: Hakko FX-888D · Budget: Pinecil
• Good solder. Rosin-core 63/37 flows and looks right. It is cheap and it matters. Kester 44 63/37
• Flux. Flux is what makes old joints let go and new joints flow. MG Chemicals flux pen · Chip Quik flux syringe
• Low-melt alloy (for surface mount). Melts old solder on both ends of a surface mount part at once, so it lifts off cleanly. Chip Quik SMD1
• Desoldering tool. Clears the old solder out of through-hole pads. Top: Hakko FR-301 · Mid: Engineer SS-02 pump · Budget: Solder wick
• Fine tweezers. For holding small surface mount parts exactly where you want them. ESD-safe tweezers
• Board holder. A third hand for the board, so both of yours are free. PanaVise circuit board holder
• Magnification. You cannot fix what you cannot see. Surface mount parts are tiny. Top: Stereo microscope · Mid: Head visor · Budget: Lighted magnifier
• Multimeter. Continuity, shorts and rail voltages. The one test that saves boards. Top: Fluke 117 · Mid: Fluke 101 · Budget: AstroAI
• ESR and capacitor tester. Checks old capacitors and your new ones before they go in. Top: Peak Atlas ESR70 · Budget: LCR-T7
• Isopropyl alcohol (99%) and a brush. For cleaning leaked goo and flux. Use the high-percentage kind. MG Chemicals 99.9% isopropyl
• Brass tip cleaner. A clean tip transfers heat. A dirty one does not. Hakko 599B
• Fume extractor. Pulls the smoke away from your face. Hakko FA-400 · Budget: Small bench fan
• Precision screwdrivers. Most old gear uses a mix of Phillips, Torx and security bits. iFixit Pro Tech Toolkit
• Kapton tape. Heat-proof tape to protect parts that sit close to the one you are changing. Kapton tape

Safety

• Good airflow, or a fume fan. Solder smoke is not for breathing.
• Safety glasses on. Solder spits and clipped legs fly.
• Iron in its stand when you are not holding it. Know where the cord is.
• Touch bare metal first, or use a wrist strap. Static kills old chips.
• No tube, no mains power supply. Leave those to a professional.
• Wash your hands after, especially if you used leaded solder.

Values are shown as published in the guides above, and boards changed during production. Check the board in front of you. A recap involves hot tools and, on some machines, dangerous voltages. You do it at your own risk.

More

• All recap guides
• The interactive Recap Bench
• Fix a dead vintage computer
• Apple IIGS on the timeline