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Philips VG-5000 Capacitor Replacement Guide

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Philips VU-0022 power supply circuit diagram
The VU-0022 power supply circuit diagram. Its electrolytics are the reservoirs C196 and C197 on the mains side, C194, C195 and C198 around the TEA1039 controller, and C199 to C205 on the three outputs.

The Philips VG-5000 itself has only eight electrolytic capacitors, all small. The electrolytic that fails in practice is in the external VU-0022 power supply: C203, the 4700 µF reservoir on the +5 V output.[1][2] For the general signs of a failed capacitor see Capacitor Failure Symptoms.

Computer

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Electrolytic capacitors in the VG5000 (Service sa parts list)
Board Positions Value Philips code
Main board 2069 to 2074 (6) 1 µF 63 V 4822 124 40242
Cassette interface 2001, 2005 10 µF 4822 124 21218

[1]

The parts list gives no voltage rating for the two 10 µF capacitors on the cassette board; read it from the parts on your board. The other capacitors on both boards are 1 nF and 22 nF disc ceramics and 100 pF plate ceramics.[1] One of the 1 µF capacitors, 2071, is the supply decoupling beside the Z80A.[3] Their positions are on the component layout on page 6 of the service manual.[4]

VU-0022 power supply

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VU-0022 electrolytic capacitors (Philips service manual 4822 727 15121)
Ref Value Philips code Circuit
C196, C197 22 µF 385 V 4822 124 21306 Mains reservoirs after the BYW55 bridge, about 310 V
C194 680 µF 25 V Supply to the TEA1039 controller (18 V)
C195 22 µF 40 V TEA1039 pin 2
C198 47 µF 25 V Auxiliary winding, via D184
C203 4700 µF 10 V 4822 124 21408 +5 V reservoir after D189
C201 330 µF 10 V +5 V output after the choke S210; R168 sets 5 V across it
C200 330 µF 4822 124 21503 +12 V reservoir after D187
C199 220 µF 16 V +12 V output after the choke S209
C204 150 µF 25 V -12 V reservoir after D186
C205 47 µF 25 V -12 V output after R159

[5][6][7]

The values and voltage letters of the capacitors without a Philips code are read from the circuit diagram, which marks voltage ratings with code letters (d 10 V, e 16 V, f 25 V, g 40 V); the parts list in the hosted copy covers only C175, C176, C196, C197, C200 and C203, and gives no voltage for C200.[5][6] The later version of the board, made from mid-November 1984, has only one of the two large mains reservoir capacitors.[2]

C203

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In the VG 5000 Bazar repairs, C203 was short-circuited in all three failed supplies: it ran warm, the +5 V output was erratic and the +12 V output was below 7 V. Replacing it restored the supplies.[2]

  1. Unplug the supply and open it: four cross-head screws in the corner wells, then lift off the cover. Unplug the on/off switch lead and lift the switch out to free the board.[2]
  2. The original part is an axial capacitor, 16 mm in diameter and 32 mm long, next to the output cable. Fit 4700 µF 10 V or higher. An axial part fits the original holes; a radial part also fits if you clear the two spare solder-filled holes the board has for it, which keeps it clear of the output cable.[2]
  3. Observe the polarity: the positive lead goes to the hole furthest from the ground, +12 V and +5 V wires.[2]
  4. Measure the outputs before reconnecting the computer: about +5.2 V, +11 V and -11.4 V on a working supply. If they are still wrong, other parts are at fault.[2]

Keep clear of the primary side while the supply is plugged in: the mains reservoirs C196 and C197 charge to about 310 V, and the hatched printing on the board marks the parts connected directly to the mains.[5][7]

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References

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  1. ↑ 1.0 1.1 1.2 Service sa, Micro-ordinateur VG5000/18/19/39, service manual EV 84-12, 4811 740 17312, 1984, p. 2: parts lists for the main board and the cassette interface. Hosted as File:Philips VG5000 Service Manual 4811 740 17312.pdf.
  2. ↑ 2.0 2.1 2.2 2.3 2.4 2.5 2.6 VG 5000 Bazar, "Dépanner une alimentation VU-0022", version 1.0 of 17 March 2018, revised 3 February 2025. http://vg5000bazar.free.fr/html/depannage/vu0022.htm
  3. ↑ Service sa, Micro-ordinateur VG5000/18/19/39, p. 8: central unit circuit diagram (2071, 1 µF, on the Z80A supply). Hosted as File:Philips VG5000 Service Manual 4811 740 17312.pdf.
  4. ↑ Service sa, Micro-ordinateur VG5000/18/19/39, p. 6: component-side layout. Hosted as File:Philips VG5000 Service Manual 4811 740 17312.pdf.
  5. ↑ 5.0 5.1 5.2 Philips, Service Manual, External power supply VU-0022, p. 3: circuit diagram (drawing 36498 C12). Hosted as File:Philips VU-0022 Power Supply Service Manual 4822 727 15121.pdf.
  6. ↑ 6.0 6.1 Philips, Service Manual, External power supply VU-0022, p. 4: parts list. Hosted as File:Philips VU-0022 Power Supply Service Manual 4822 727 15121.pdf.
  7. ↑ 7.0 7.1 Philips, Service Manual, External power supply VU-0022, 4822 727 15121, p. 2: notes and adjustment. Hosted as File:Philips VU-0022 Power Supply Service Manual 4822 727 15121.pdf.


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