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Nintendo Famicom Capacitor Replacement Guide

From RetroTechCollection

Recapping a Nintendo Famicom restores stable video, audio, and power delivery, curing many “mystery” resets, sprite glitches, and audio hum. While the Famicom’s linear power supply is robust, original aluminium electrolytic capacitors are now well past their design life and prone to failure.

Visual Inspection & Failure Signs

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  • Bulging or leaking cans – especially the large 1000 µF main filter cap.
  • Brown or white residue – crust at the base of capacitors, especially near the audio section.
  • Video noise or rolling lines – often tracks to dried-out decoupling caps on the PPU or main +5V rail.
  • Random resets or power loss – main filter capacitor or reset RC cap failure.
  • Hum or distortion on audio – output coupling or decoupling caps degraded.

If one capacitor shows trouble, replace all electrolytics on the board.

Famicom Mainboard Capacitor List

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The original Famicom (HVC-CPU-xx) uses a small number of electrolytic capacitors. Always cross-check your silkscreen and board revision.

HVC-CPU-07/08 (Original Famicom)

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Nintendo Famicom Electrolytic Capacitors
Board ref Capacitance Voltage Purpose / rail
C7 1000 µF 16 V Main +5 V bulk (power input smoothing)
C6 47 µF 16 V Audio output coupling
C5 10 µF 16 V Power-on reset RC
C4 1 µF 50 V Video output coupling
C3 10 µF 16 V PPU decoupling
C2 10 µF 16 V CPU decoupling

Replacement Notes

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  • Polarity matters! Match the negative stripe to the silkscreen.
  • Modern replacements are much smaller; ensure leads reach.
  • Use 105°C-rated capacitors for longevity.
  • If the board revision differs, check for additional or relocated caps.

Tools & Tips

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  • Soldering iron (fine tip)
  • Solder sucker or wick
  • Isopropyl alcohol for cleaning
  • Take photos before removal for reference

Power-On Test

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After recapping, verify:

  • Stable power LED and no random resets
  • Clean video output (no rolling lines)
  • Clear, hum-free audio

If issues persist, double-check polarity and solder joints.