Recap guide
Recap the Apple II power supply
The original Astec-type supply has paper-style line-filter caps that pop and electrolytics that dry out. The power supply is the part to recap.
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.
- Astec AA11040 (Medium confidence). How to tell: Astec supplies are described as gold colored with a solder mask and user replaceable fuses. Capacitors: An Applefritter thread says a listing for the AA11040 shows only a 0.1uF RIFA while other variants used both 0.1uF and 0.22uF. Capacitor list differs from other revisions: yes. Source
- Astec AA11040B and AA11040C (Low confidence). How to tell: Model number printed on the Astec case. Capacitors: Suggested RIFA substitute ECQ-U2A104KL needs 20 mm lead spacing; a poster says the small 220uF at C12 is a known weak point. Capacitor list differs from other revisions: not known. Source
- Astec AA11042C (IIe) (Low confidence). How to tell: Model number printed on the Astec case. Capacitors: Thread points to high voltage (200V plus) AC side caps and a RIFA line filter cap, with X2 replacements advised. Capacitor list differs from other revisions: not known. Source
- Dynacomp supply (Low confidence). How to tell: Mid 1980s Dynacomp units often have bare aluminum housings; used in later IIe and Platinum IIe. Capacitors: Some earlier Dynacomp units used X1 rated safety caps instead of X2. 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.
- Popping line-filter caps (Medium confidence). A forum thread recommends swapping RIFA-style X-rated line-filter caps (0.1 and 0.22 uF seen) for polypropylene film X2 parts. It gives only the film values. Source
- Dried-out electrolytics (Low confidence). A community thread says to replace the electrolytics as well as the safety caps, but gives no part list. 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.
- Watch out: Stored charge in the supply (Medium confidence). A poster warns that supply capacitors can hold a charge after use, so let the unit sit unplugged for a while before opening it. Polarity matters only on the electrolytics. Source
- Tip: Choosing replacements (Medium confidence). The thread suggests replacing the electrolytics and the safety (X) caps, matching uF, using equal or higher voltage, matching lead spacing, keeping height equal or shorter, and preferring low ESR. Source
- Tip: Rectangular line filter cap is the smoker (Medium confidence). In an Apple IIe supply thread, posters say the rectangular RIFA-style line filter cap is the usual cause of the magic smoke and should become a mains-rated X2 part. They suggest 105C electrolytics such as Nichicon PW or Panasonic FR, one cap at a time. Source
- Watch out: Test the supply on its own (Medium confidence). The thread says to check all output voltages with the supply disconnected from the motherboard, because a failing supply can take the board with it. Brown goo inside the case is a sign something has already failed. Source
- Tip: Some Apple II+ supplies have no RIFA caps (Medium confidence). In a thread on a stored Apple II+ supply, a reply says that version has no RIFA filter caps and that only the +5V is fully regulated, the other rails being rectified and smoothed. Unloaded readings of about +11.6V and -10.4V were judged acceptable by posters. 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 II Technical Procedures, June, 1987 (Service manual)
- Apple IIe Technical Procedures, June, 1987 (Service manual)
- Apple Technical Procedures - Apple II - II Plus (Service manual)
- Apple Technical Procedures - Disk II (Service manual)
- Apple Technical Procedures - DuoDisk (Service manual)
All 5 documents for Apple II 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.
- Recapping an Apple II Power Supply (Forum) by Applefritter forum. Community advice thread; says replace electrolytics and safety caps, no part list
- Apple II and IIe power supply RIFA replacements (Forum) by Applefritter forum. Has a capacitor list. Good on why to swap the RIFA-type caps for polypropylene film X2 parts; only the film cap values are given, not the electrolytics
- Apple ][e Power Supply Unit: Re-Capping (Forum) by Applefritter forum. IIe-specific discussion with safety warnings; points at a kit seller rather than listing values
Astec AA11040 / B / C (605-5703), 100 to 120 V
This list is the electrolytics only. Console5 also lists the safety parts, which are a different kind of part: C1 (0.1 uF 250 V AC, a RIFA metallized paper cap that it says to always replace), C3 and C4 (2200 pF Y-class) and C23 (0.01 uF 250 V X-class). Mains power supply: unplug it and let it discharge first.
| Part | Value | Volts | Type |
|---|---|---|---|
| C5 | 47 µF | 250 V | check your board |
| C6 | 47 µF | 250 V | check your board |
| C7 | 220 µF | 10 V | check your board |
| C12 | 1000 µF | 10 V | check your board |
| C13 | 1000 µF | 10 V | check your board |
| C14 | 1000 µF | 10 V | check your board |
| C15 | 220 µF | 10 V | check your board |
| C16 | 220 µF | 10 V | check your board |
| C19 | 1000 µF | 10 V | check your board |
| C20 | 680 µF | 16 V | check your board |
| C21 | 330 µF | 16 V | check your board |
| C22 | 330 µF | 16 V | check your board |
| C24 | 47 µF | 250 V | check your board |
| C25 | 47 µF | 250 V | check your board |
Dynacomp 606-5001, 100 to 120 V
Console5 lists this one by value and count. The two 0.1 uF 250 V safety capacitors are not in this list. Mains power supply: unplug it and let it discharge first.
| Part | Value | Volts | Type |
|---|---|---|---|
| 1000 µF x 4 | 1000 µF | 10 V | check your board |
| 100 µF x 2 | 100 µF | 200 V | check your board |
| 10 µF x 3 | 10 µF | 16 V | check your board |
| 220 µF x 2 | 220 µF | 10 V | check your board |
| 330 µF x 2 | 330 µF | 16 V | check your board |
| 470 µF x 1 | 470 µF | 6.3 V | check your board |
| 680 µF x 1 | 680 µF | 16 V | check your board |
Astec AA11042 / C (699-0161-A), 220 to 240 V
Electrolytics only. The safety parts at C1 (0.1 uF) and C23 (0.47 uF), both rated 250 V AC, are separate and Console5 says to replace them too. Mains power supply: unplug it and let it discharge first.
| Part | Value | Volts | Type |
|---|---|---|---|
| C5 | 47 µF | 250 V | check your board |
| C6 | 47 µF | 250 V | check your board |
| C7 | 220 µF | 10 V | check your board |
| C12 | 1000 µF | 16 V | check your board |
| C13 | 1000 µF | 16 V | check your board |
| C14 | 1000 µF | 16 V | check your board |
| C15 | 330 µF | 10 V | check your board |
| C16 | 330 µF | 10 V | check your board |
| C19 680 uF on some revisions. Console5's kits use 1000 uF. | 1000 µF | 16 V | check your board |
| C20 | 1000 µF | 16 V | check your board |
| C21 | 330 µF | 16 V | check your board |
| C22 | 330 µF | 16 V | check your board |
| C24 | 47 µF | 250 V | check your board |
| C25 | 47 µF | 250 V | check your board |
Disk ][ analog card 650-0103
Three capacitors.
| Part | Value | Volts | Type |
|---|---|---|---|
| C2 | 220 µF | 16 V | check your board |
| C4 | 470 µF | 6.3 V | check your board |
| C5 | 10 µF | 35 V | check your board |
Disk ][ Shugart motor board
Three matching 10 uF parts.
| Part | Value | Volts | Type |
|---|---|---|---|
| C1 | 10 µF | 35 V | check your board |
| C5 | 10 µF | 35 V | check your board |
| C6 | 10 µF | 35 V | check your board |
Disk ][ interface card 650-X104
One capacitor.
| Part | Value | Volts | Type |
|---|---|---|---|
| C2 | 22 µF | 16 V | check your board |
Apple video overlay card
Four capacitors.
| Part | Value | Volts | Type |
|---|---|---|---|
| C1 | 47 µF | 16 V | check your board |
| C8 | 47 µF | 16 V | check your board |
| C23 | 47 µF | 16 V | check your board |
| C30 | 100 µF | 16 V | check your board |
Shopping list
54 capacitors in all, grouped by value. Buy a few spares.
- 8 x 47 µF, 250 V (check your board): Amazon · eBay
- 8 x 1000 µF, 10 V (check your board): Amazon · eBay
- 6 x 220 µF, 10 V (check your board): Amazon · eBay
- 6 x 330 µF, 16 V (check your board): Amazon · eBay
- 5 x 1000 µF, 16 V (check your board): Amazon · eBay
- 4 x 10 µF, 35 V (check your board): Amazon · eBay
- 3 x 10 µF, 16 V (check your board): Amazon · eBay
- 3 x 47 µF, 16 V (check your board): Amazon · eBay
- 2 x 100 µF, 200 V (check your board): Amazon · eBay
- 2 x 330 µF, 10 V (check your board): Amazon · eBay
- 2 x 470 µF, 6.3 V (check your board): Amazon · eBay
- 2 x 680 µF, 16 V (check your board): Amazon · eBay
- 1 x 22 µF, 16 V (check your board): Amazon · eBay
- 1 x 100 µF, 16 V (check your board): Amazon · eBay
- 1 x 220 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 2 Power Supply Cap Kit P N 605 5703 Astec AA11040B AA11040 B
- Apple 2 Power Supply Cap Kit Dynacomp 606 5001
- Apple 2 Power Supply Cap Kit Astec AA11042C AA11042 C 240V
- Apple 2 Disk Floppy Drive Cap Kit Analog Motor PCB
- Apple II Video Overlay Card Electrolytic Cap Kit Apple 2
Skip the sourcing
While you are in there
Affiliate links. As an Amazon Associate I earn from qualifying purchases. These links only search by name. Disclosure
Step by step
- 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.
- 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.
- 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.
- 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.
- 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.
- 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.
- 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.
- 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.
- 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.
- 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.
- 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.