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Recap guide

Recap the Atari 7800

Only a few electrolytics. Owners argue about whether recapping a working unit is needed, though one example had a slightly leaked cap.

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

Check first. A recap is not always the answer here, so look at the guides before you order parts.

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.

  • C025233-001 (NTSC, 1984-1986) (Medium confidence). How to tell: Original NTSC board with the unused expansion port. Capacitors: No cap difference documented. Capacitor list differs from other revisions: not known. Source
  • C025233-002 (NTSC, 1986-1992) (Low confidence). How to tell: Revised NTSC board with a timing circuit for 2600 compatibility; most expansion-port-less consoles use it, and the timing circuit later stopped being populated. Capacitors: No cap difference documented; an AtariAge thread says only three electrolytics need replacing on a 7800, without naming the board. Capacitor list differs from other revisions: not known. Source
  • C300633-001 (PAL, 1989-1993) (Low confidence). How to tell: PAL board with green power LED and a different faceplate; French variant has a 13-pin DIN RGB connector. Capacitors: No cap information; one page notes PAL units had at least two different 240V power pack designs. 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.

  • To recap or not (Low confidence). One thread notes three electrolytics worth replacing and one that leaked slightly, and has a fair debate on recapping at all. It also warns that a 2600 PSU is too weak for a 7800. 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.

  • Tip: Which parts besides the three electrolytics (Low confidence). In the same recap thread, posters suggested swapping silver polystyrene caps of 820pF for MLCC ceramics and the green film caps for new film caps, while another said the green parts on the paddle inputs have no known failures. Several posters warned against replacing parts just because they are old, since it risks damage. Source

Before you start

  • Boards changed during production. Check your board number against the guides before you order parts.

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.

  • 7800 recap/refresh (Forum) by MooseHead (AtariAge). Recap plus PSU/regulator and composite mod with a fair debate on whether to recap at all. Mentions film and MLCC swaps; no board revisions. Warns a 2600 PSU is too weak for a 7800

Atari 7800 main board

Three capacitors. Console5 does not split this list by board revision. It says a 6.3 V part is fine for the two 220 uF positions.

PartValueVoltsType
C22 6.3 V is fine here.220 µF16 Vcheck your board
C61 6.3 V is fine here.220 µF16 Vcheck your board
C622200 µF16 Vcheck your board

Shopping list

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

  • 2 x 220 µF, 16 V (check your board): Amazon · eBay
  • 1 x 2200 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.

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

  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

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.

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