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Sony HB-F1XV General Maintenance

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Sony HB-F1XV main board
HB-F1XV main board. The HIC-1 module is at the top right, the coin cell at the right and the reservoir capacitor at the top left.

The Sony HB-F1XV has the same main board layout as the HB-F1XDJ, and the author of an HB-F1XDJ maintenance page states that the HB-F1XV's hardware is the same.[1][2] No service manual or maintenance schedule for the HB-F1XV has been found. The step-by-step procedures for the shared hardware are in the Sony HB-F1XDJ General Maintenance guide. The notes below add what owners have reported on the HB-F1XV itself.

Safety

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The rating label gives AC 100 V, 50/60 Hz, 31 W.[3] The transformer is inside the case and mains voltage is present at its left-hand side when the lid is off.[2] Unplug the machine before opening it, and run it through a step-down transformer where the mains is 220 to 240 V.

Opening the case

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Follow the sequence in Sony HB-F1XDJ General Maintenance#Opening the case: five screws underneath and one at the video connector, the three cables from the top cover, the keyboard and its shield, the drive on its bracket, the heat sink, then the main board.[2] When closing the case, keep the three cables from the top cover in the gap between the drive and the keyboard.[4]

Batteries

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Two AA cells run the calendar clock. The MSX Resource Center recommends lithium AA cells or Eneloop rechargeables and advises against alkaline cells, because they leak sooner or later.[5] Take the cells out before storing the machine.[6] If they have leaked, see Battery Explosion, Capacitor or Corrosion Damage.

A coin cell is soldered to the main board. On the HB-F1XDJ it backs the MSX-JE dictionary SRAM.[2] Wierzbowsky replaced the long-dead soldered cell in his HB-F1XV with a plastic CR2032 socket.[7] Fix any socket down so that it cannot touch the shield above it, and do not solder to an untabbed cell.[2]

Floppy drive belt

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The MSX Resource Center names the drive belt as the HB-F1XV's main cause of failure: it goes soft with age. A replacement is 59 mm in diameter (186 mm long), 2.8 mm wide and 0.4 mm thick.[5] Belt replacement and the symptoms of a failed belt are described for the identical drive in Sony HB-F1XDJ General Maintenance#Floppy drive; see also Floppy Drive Repair.

HIC-1 capacitors

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The three surface-mount electrolytics on the HIC-1 module leak with age and corrode the module.[4] Wierzbowsky replaced the three on his HB-F1XV before any leak appeared, using tantalum parts.[7] Replace them before they leak; values and methods are in the Sony HB-F1XV Capacitor Replacement Guide.

Keyboard

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Dirt and liquid between the keys break the printed traces on the keyboard film.[8][2] The repair with conductive silver ink is described in Sony HB-F1XDJ General Maintenance#Keyboard and controls. The MSX Resource Center also links a keyboard repair kit from classicpc.org for the HB-F1XD, XDJ and XV.[5]

Connectors

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Cracked solder joints on the DIN, RCA and joystick connectors cause flickering video and crackling sound when a lead is moved; reflow them.[6]

Checklist

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  1. Take out or check the AA clock cells.
  2. Open the case and inspect the HIC-1 module for leakage.
  3. Check that the MSX-JE dictionary survives a power cycle; if not, replace the coin cell.
  4. Check the drive belt.
  5. Test every key and both joystick ports, and move each video and audio lead while watching the picture.

For faults see the Sony HB-F1XV Troubleshooting Guide.

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References

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  1. ↑ File:Sony HB-F1XV main board.jpg, photograph of an HB-F1XV main board uploaded to the MSX Resource Center wiki by Gdx on 4 April 2016. Read from it: the same layout as the HB-F1XDJ board, with "MSX2+SYSTEM" and "AUDIO & VIDEO" printed on it, the large reservoir capacitor at top left, the HIC-1 module at the rear right, the coin cell at the right, and a trimmer marked CV2 beside test point TP1 near the front right.
  2. ↑ 2.0 2.1 2.2 2.3 2.4 2.5 8ビットパソコン HB-F1XDJ (MSX2+) ネタ, 25 October 2016—link(accessed 2026-10-21) In Japanese. An owner's notes on the HB-F1XDJ, which he says apply to the HB-F1XV because its hardware is the same: kanji dictionary SRAM backed by a tabbed Sony CR2032 soldered to the main board under the keyboard, which clears the dictionary at every start when flat; calendar and clock backed by two AA dry cells, manganese cells recommended, alkaline cells acceptable but watch for leaks; Mitsumi D357B 720 KB drive without VFO, with a rubber belt that stretches or melts; floppy drive powered by +5 V only, 34-pin signal connector, pin 1 on the left; AC 100 V present at the left-hand side of the case; disassembly sequence; old jumper wires on the main board come away easily and the board's joints and traces are fragile; some lots lose FM volume, cured by replacing C99, a 50 V 1 µF electrolytic in the YM2413 block on the left of the main board; quaternary-salt electrolytics used in places, which leak and break traces when the machine is stored unpowered in damp places; match the height of replacement capacitors; keyboard film traces corroded by spilled liquid, repaired with conductive silver ink; joystick ports gold-plated but prone to dirty contacts; a start-up password can be set and is cleared by holding GRAPH and STOP while switching on; after a drive swap, a reversed signal cable leaves the drive lamp lit and makes the head chatter, and a drive that is not recognised gives "Disk Offline".
  3. ↑ Rating label of the HB-F1XV, photographed for the MSX Resource Center wiki (File:Sony HB-F1XV rating label.jpg, uploaded by Mars2000you, 24 January 2023): "MODEL HB-F1XV PERSONAL COMPUTER 100V 31W 50/60Hz", ソニー株式会社, Made in Japan.
  4. ↑ 4.0 4.1 Urgent alert to MSX2/2+ owners: suicide capacitors on HIC-1 daughterboard, July 2015 onwards—link(accessed 2026-10-21) Opening post by sd_snatcher, 19 July 2015: the HIC-1 (EMC-NX0039) module in the Sony HB-F1XV, HB-F1XDJ, HB-F1XDmkII and HB-F1XD and the Panasonic FS-A1, FS-A1mkII and FS-A1F carries three SMD aluminium electrolytics that leak and damage the board: C10 10 µF 16 V, C14 10 µF 16 V and C22 100 µF 16 V, C22 the worst; ceramic or tantalum replacements in 3216 (10 µF) and 4532 or 6032 (100 µF) sizes, rated 16 V or more. Reply by jltursan: two HB-F1XD and one HB-F1XV affected, the first symptom usually lower sound volume. Reply by RetroTechie: cut through the solder or use two irons to lift the old parts without heating the board. Reply by dublevay, 5 September 2020, on an HB-F1XV: the original 100 µF part was a 6.3 V type marked 6A and the 10 µF parts were 16 V; hot air blew three small resistors (820 Ω, 1 kΩ and 0 Ω) off the module, which he refitted; he fitted Kemet tantalums first; the band on a tantalum marks its positive end, unlike an aluminium electrolytic, which marks the negative; after fitting tantalums, then Panasonic HD (10 µF, 16 V) and HC (100 µF, 6.3 V as original) SMD electrolytics chosen to match the original sizes, there was still no composite or RF picture until the 22 µH inductor (marked 220) below the lower 10 µF capacitor, which had a bad joint, was reflowed; RGB worked throughout. Reply by Louthrax, 23 December 2025, on reassembling an HB-F1XDJ: the three cables from the lamp and slider housing go in the space between the drive and the top of the keyboard, not on top of the drive.
  5. ↑ 5.0 5.1 5.2 Sony HB-F1XV, MSX Resource Center wiki—link(accessed 2026-10-21) Community specification and maintenance page: MSX2+, released 1989-10-21 at ¥69,800, the last MSX made and sold by Sony; S1985 MSX-Engine, Zilog Z0840004SPC CPU, MB89311 floppy controller, V9958, YM2413; 64 KB RAM in slot 3-0 plus 16 KB SRAM; 720 KB drive; three or four disks supplied (F1 Synth, F1 Tool Disk II, a Japanese word processor with MSX-DOS 1, and on some units a Story Disk). Maintenance notes: the drive belt is the main cause of failure and softens with age (59 mm diameter, 186 mm long, 2.8 mm wide, 0.4 mm thick); HIC-1 daughterboard with three SMD electrolytics that leak; FM crackle fix (C99 replaced with a wire, C20 with a non-polarised capacitor of the same value, after Niga; a 4.7 kΩ resistor between C20 and the sound input can be added but is not essential); link to a keyboard repair kit for the HB-F1XD, XDJ and XV from classicpc.org; lithium AA or Eneloop cells recommended, alkaline advised against.
  6. ↑ 6.0 6.1 Vulnerable MSX hardware, MSX Resource Center wiki—link(accessed 2026-10-21) All MSX2 and later machines have a battery for the real-time clock; drained batteries, alkaline ones especially, leak; take removable batteries out before storage; lithium AA cells as an alternative. Lists the HB-F1XD, HB-F1XDJ ("the ELNA caps are risky, the Nichicon ones are ok"), HB-F1XDmk2 and HB-F1XV among models with leaky capacitors. Fractured solder joints on DIN, RCA and DE-9 connectors cause flickering video and crackling sound; reflow them.
  7. ↑ 7.0 7.1 Sony HB-F1XDJ capacitor leakage repair guide, 21 December 2017—link(accessed 2026-10-21) Repair report by Omega: an HB-F1XDJ that sometimes would not start, was unstable when it did, and produced wrong key presses (EF for E). Electrolyte had leaked round the HIC module and from through-hole capacitors on the main board, through to the solder side; all four ELNA 47 µF capacitors (6.3 V, per his later correction) had leaked and lost their capacitance. He desoldered the SMD capacitors with hot air, cleaned with isopropyl alcohol, neutralised with vinegar, scraped the pads, used SMD flux and fitted Panasonic parts, replaced every ELNA electrolytic on the board, left the Nichicon ones, and removed the flat CR2032. The capacitors on the HIC module served only the RGB to composite circuit; RGB passes through the module unaffected. Some copper was corroded but no traces needed repair, and the machine then started every time and the keyboard worked. He advises HB-F1XDJ owners to check for leakage and have the ELNA capacitors replaced preventively, because broken traces mean labour-intensive repairs. Reply by Wierzbowsky, 7 January 2018, on an HB-F1XV: replaced the three daughterboard capacitors with 10 µF 16 V size B and 100 µF 16 V size D tantalums before any leak, and replaced the soldered cell, which he calls the clock battery, with a socket for a CR2032.
  8. ↑ MSX2+, Japanese Wikipedia—link(accessed 2026-10-21) In Japanese. The HB-F1XDJ was released on 21 October 1988; its case was carried over from the MSX2 HB-F1XD series; MSX-JE built in. After about a year of use the FM sound on the HB-F1XDJ became quieter because of a circuit fault, which Sony dealt with by replacing a capacitor. Across the series, dirt getting in between the keys breaks the traces on the keyboard film. The HB-F1XV changed the colouring and expanded the bundled software.