Jump to content

Sanyo MPC-200 Capacitor Replacement Guide

From RetroTechCollection
Sanyo MPC-200 power supply area
The two large electrolytic capacitors of the MPC-200's supply, next to the heatsink

No capacitor list, parts list or circuit diagram for the Sanyo MPC-200 has been published, and no service manual for it or for the Japanese MPC-2 is held in the MSX Archive's collection of service manuals.[1] Sanyo's Spanish operating instructions contain no circuit information.[2] Read the values from your own board.

What is known

[edit | edit source]
  • The supply is built from a mains transformer, labelled PT0129, with a fuse beside it marked F101, T1A 250V.[3]
  • Two large radial electrolytic capacitors stand side by side next to a part on a black heatsink, on the low-voltage side of the transformer.[3] They are the first capacitors to record and replace.
  • Smaller radial electrolytics are spread across the main board.[3]
  • The machine draws 6 W from 220 V mains.[4]

No Sanyo values for any of these positions are known.

Which to replace first

[edit | edit source]

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.[5] On the MPC-200 that means:

  1. The two large capacitors beside the heatsink.
  2. Any capacitor near the video and sound circuits, if the picture or sound is poor.
  3. The rest, only if they leak, bulge, or a rail is noisy.

Recording the board

[edit | edit source]
  1. Unplug the machine and open the case as described in the Sanyo MPC-200 General Maintenance guide.
  2. Photograph the board from above, then each electrolytic close up so the printing on its sleeve can be read.
  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, in a size that fits.
Template for the MPC-200's own list
Ref Value Voltage Temperature Diameter × height Position Notes
Beside the heatsink
Beside the heatsink

Procedure

[edit | edit source]
  1. Unplug the mains lead.
  2. Photograph and unplug the leads to the board behind the cartridge connectors and to the lamp board.[3]
  3. Lift the main board out carefully. The Toshiba T7775 MSX-Engine is a surface-mounted chip on its underside, so do not flex the board.[6]
  4. Replace one capacitor at a time, stripe on the same side as the original.[5]
  5. Clean off any electrolyte and check the tracks round each position. See Capacitor Failure Symptoms.
  6. Refit the board and the leads.

After the recap

[edit | edit source]

Switch on with no cartridge fitted and measure the rails at a slot: +5 V on pins 45 and 47, +12 V on pin 48 and −12 V on pin 50, against pin 41 or 43.[7] Then check that MSX-BASIC starts, that a cartridge runs in each slot, and that the picture and sound are clean. Remaining faults are covered in the Sanyo MPC-200 Troubleshooting Guide.

[edit | edit source]

References

[edit | edit source]
  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. ↑ Sanyo, Ordenador personal MSX: Instrucciones para el funcionamiento (MPC-200), part number 3P05386 (Y3BL); pages 1 to 14 cover parts, connections, operation, precautions, problems and specifications. In Spanish. Hosted here as Sanyo MPC-200 Operating Instructions.
  3. ↑ 3.0 3.1 3.2 3.3 File:Sanyo MPC-200 inside.jpg and File:Sanyo MPC-200 power supply area.jpg, photographs of an opened MPC-200 uploaded to the MSX Resource Center wiki by Rderooy. Read from them: transformer PT0129; fuse holder F101 marked "T1A 250V"; two large radial electrolytic capacitors side by side next to a part on a black heatsink; a column of four diodes below them; smaller radial electrolytics spread across the main board; main board labelled UF063481 and marked MCL437F. The printing on the capacitors cannot be read at the resolution of the photograph.
  4. ↑ File:Sanyo MPC-200 rating label.jpg: "MPC-200(SP)", 220 V, 50 Hz, 6 watts.
  5. ↑ 5.0 5.1 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.
  6. ↑ File:Sanyo MPC-200 T7775 MSX-Engine.jpg, photograph of the underside of the main board: surface-mounted Toshiba T7775 MSX-Engine.
  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.


Retrieved from "https://retrotechwiki.com/index.php?title=Sanyo_MPC-200_Capacitor_Replacement_Guide&oldid=28054"