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Sanyo PHC-35J Wavy Capacitor Replacement Guide

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Sanyo PHC-35J power supply section
The PHC-35J supply: the large primary capacitor beside fuse F501 at the top left, and C551, C553, C554, C556 and C557 on the secondary side at the right

No capacitor list, parts list or circuit diagram for the Sanyo PHC-35J Wavy has been published, and no service manual for any Sanyo MSX is held in the MSX Archive's collection.[1] The positions below are read from USB Secret Base's photographs of the main board. Read the values from your own board.

What is known

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The supply is in the top left corner of the main board, which is marked 2CA4B10202.[2] These capacitors can be identified in the photographs:[3][4]

Capacitors identified on the PHC-35J
Ref Where Notes
Large primary electrolytic Supply, beside F501 Largest on the board; designator and value hidden in the photograph
C551 Supply, secondary side Large
C552, C553 Supply, secondary side, top right Large; C552 is at the edge of the close-up
One unmarked Supply, secondary side, between C553 and C551 Large; designator hidden in the photograph
C554 Supply, secondary side, right Medium
C556, C557 Supply, secondary side, lower right Small
C501 Supply, mains input Green film capacitor, not an electrolytic
C505, C507 Supply Yellow safety capacitors, not electrolytics
C150, C151, C152 Beside the V9958 Small electrolytics in a row
C156, C157, C158 Between the audio and video sockets and the RF modulator Small electrolytics

No values for any position are known. The PHC-70FD's primary capacitor is 330 µF 160 V, but its supply uses a different transformer, so do not assume the PHC-35J's is the same.[5][3]

Which to replace first

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General advice on MSX recapping from the MSX Resource Center forum is to replace the main power supply's capacitors whatever their condition, to judge the audio and video capacitors by the output, and to leave the small decoupling capacitors on the logic board unless there is a reason.[6] On the PHC-35J that means:

  1. The secondary-side capacitors of the supply: C551 to C557 and the unmarked one beside C551.
  2. The large primary capacitor. It runs at rectified 100 V mains, so copy its voltage rating exactly or go higher.
  3. The capacitors round the video and audio outputs (C150 to C158), if the picture or sound is poor.

Recording the board

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  1. Unplug the machine, open the case and measure across the large primary capacitor to make sure it has discharged.
  2. Photograph the supply corner and the rest of the board from above, then each electrolytic close up.
  3. For each capacitor, write down the designator, capacitance, voltage, temperature rating, diameter and height, and which side the stripe faces.
  4. Order replacements of the same capacitance and at least the same voltage. Use 105 °C parts in the supply.
Template for the PHC-35J's own list
Ref Area Value Voltage Temperature Diameter × height Notes
(primary) Supply Designator hidden in the published photograph
C551 Supply
C552 Supply
C553 Supply
C554 Supply
C556 Supply
C557 Supply

Procedure

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Warning: the supply's primary side carries mains voltage, and the large primary capacitor can stay charged after the plug is pulled.

  1. Take out the clock batteries and open the case as described in the Sanyo PHC-35J Wavy General Maintenance guide.
  2. Free the main board from the case to reach the solder side, photographing each connector first.
  3. Replace one capacitor at a time, stripe on the same side as the original.[6]
  4. Clean off any electrolyte and check the tracks. See Capacitor Failure Symptoms.
  5. Refit the board and its connectors.

After the recap

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Switch on with no cartridge fitted and measure the rails at a cartridge slot: +5 V on pins 45 and 47, +12 V on 48 and −12 V on 50, against pin 41 or 43.[7] Then check that the machine starts to BASIC and that the picture and PSG sound are clean. Remaining faults are covered in the Sanyo PHC-35J Wavy Troubleshooting Guide.

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References

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  1. ↑ Index of /pub/msx/docs/service_manuals, MSX Archive—link(accessed 2026-10-21) Directory of MSX service manuals; none for any Sanyo machine.
  2. ↑ File:Sanyo PHC-35J main board.jpg, photograph of the component side from USB Secret Base: board marked 2CA4B10202, 2CA0U20391 and CMK-54X; the supply at the top left; radial electrolytics round the supply, the video output section and the V9958.
  3. ↑ 3.0 3.1 File:Sanyo PHC-35J power supply section.jpg, from USB Secret Base: fuse F501; the large primary electrolytic beside it (its designator and value cannot be read); green film capacitor C501 and the mains filter; bridge D501; IC501 under a metal cover; transformer T501 labelled 0027A; yellow capacitors C505 and C507; on the secondary side electrolytics C551, C553, C554, C556 and C557, with D551 to D553, D555, D556, IC552 and IC553.
  4. ↑ PHC-35J, USB Secret Base—link(accessed 2026-10-21) In Japanese. Close-up photographs of the main board, including the area round the V9958 and video RAM (img/vram.jpg), which shows electrolytics C150, C151, C152, C156, C157 and C158 between the audio and video sockets, the RF modulator and the V9958, and C552 at the edge of the supply.
  5. ↑ Repair-Bas, Ombouw Sanyo Wavy PHC-70FD(2) naar 230 Volt (3-page PDF, in Dutch), https://repairbas.file-hunter.com/docs/other/Sanyo%20Wavy%20-%20230%20Volt%20ombouw.pdf, retrieved 2026-10-21. The PHC-70FD's C502 is 330 µF 160 V; the photographs show its transformer T501 marked AE0130.
  6. ↑ 6.0 6.1 Recap recommendations, June 2018—link(accessed 2026-10-21) Reply by RetroTechie, 23 June 2018: in an MSX, the electrolytics used for supply bypassing round the board can often be removed without the machine stopping, those in the audio and video circuits show their condition in the output, and those in the main power supply are worth replacing whatever their condition; replace one capacitor at a time. Other replies recommend Rubycon, Chemi-Con, Nichicon or Panasonic parts from established distributors.
  7. ↑ MSX Cartridge slot, MSX Resource Center wiki—link(accessed 2026-10-21) Standard MSX cartridge slot pinout: pins 41 and 43 GND, 45 and 47 +5 V, 48 +12 V, 50 −12 V.


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