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Philips Videopac G7000 Capacitor Replacement Guide

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Philips Videopac G7000 power supply schematic (SM CS 75 068)
The G7000/20/35/53 supply: C1 in the power unit, C876 and C816 on the board (Philips, CS 75 074)

The Philips Videopac G7000 was built on at least two main boards, each documented by its own Philips service manual. The parts list in manual CS 75 068 (G7000/20/35/53) gives every electrolytic capacitor with its value and voltage rating; manual CS 61 799 gives values only, partly in its parts list and partly on the circuit diagrams.[1][2][3] Identify your board before ordering parts: the CS 75 068 board uses designators in the 600s to 800s, the CS 61 799 board IC1 to IC30 and C1 to C131.[4][3] The internal supplies of the G7000/22, /23 and /37 are not covered by either manual. For failure signs in general see Capacitor Failure Symptoms.

Before replacing anything

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Warning: the external power unit contains the mains transformer and fuse, and the internal supplies of the /22, /23 and /37 run from mains voltage.[4][5]

Check the supply first, as on the troubleshooting guide: the power unit's output, then 5 V at the output of each regulator.[6]

Board of manual CS 75 068 (G7000/20/35/53)

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Main board

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Main board electrolytic capacitors (service manual CS 75 068, parts list and circuit diagram)
Ref Value Rating Philips part no. Where it connects (circuit diagram)
C876 4700 µF 25 V 4822 124 70316 Reservoir after connector P4 and chokes S696, S697, at the inputs of regulators IC681 and IC682
C816 15 µF 40 V 4822 124 20709 In parallel with C876 at the regulator inputs
C871 47 µF 25 V 4822 124 20699 +B supply of the PAL colour encoder IC679, with C865 (1 nF), feeding pins 1 and 6 through R743 (3 kΩ)
C850 10 µF 25 V 4822 124 20697 +C supply at pin 28 (VCC) of the 8245, IC652
C853 10 µF 25 V 4822 124 20697 On the +A supply line at the divider IC674
C782 10 µF 25 V 4822 124 20697 With D689 (1N4148) and R744 (33 kΩ) at the set input of flip-flop IC659a
C783 1 µF 63 V 4822 124 20722 RESET input, pin 4, of the 8048, IC651
C812 1 µF 63 V 4822 124 20722 Clear input, pin 1, of the address latch IC655 (74LS175), through R769 (4.7 kΩ)
C779 1 µF Not printed 4822 124 20722 Not located on the scanned circuit diagram

[1][4]

C779 has the same Philips part number as C783 and C812, which the list rates at 63 V.[1] The circuit diagram also draws C873, at the supply pin of the oscillator IC680, with the electrolytic symbol, but it prints no value and the parts list does not include it; read the part on your board.[4] The trimmer C777 (3 to 10 pF) sets the colour reference frequency and is not an electrolytic.[1][7]

UHF modulator U100

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Philips Videopac G7000 UHF modulator schematic (SM CS 75 068)
U100 circuit diagram with C607 to C611 (Philips)
Modulator electrolytic capacitors (service manual CS 75 068, pp. 3 and 5)
Ref Value Rating Philips part no. Where it connects
C607 100 µF 10 V 4822 124 20679 Video input P8-3 coupling
C608 10 µF 25 V 4822 124 20697 Supply decoupling of the 559.25 MHz oscillator TS601
C609 1 µF 63 V 4822 124 20722 Sound input P8-1 coupling to the sound oscillator
C610 10 µF 25 V 4822 124 20697 Supply decoupling of the sound oscillator TS602
C611 10 µF 25 V 4822 124 20697 +5 V decoupling after R619, at the supply of TS603

[1][8]

Philips's adjustment notes allow only L650 to be turned in U100; leave the other coils and trimmers alone while you work on it.[7]

Power unit

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The external power unit has one electrolytic, C1, 2200 µF, across the bridge rectifier output. The circuit diagram gives its value but neither manual gives its voltage rating.[4][3] C876, on the same supply line on the board side of P4, is rated 25 V, and an unloaded unit reads up to about 14 V.[1][9]

Board of manual CS 61 799

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Philips Videopac G7000 power supply schematic (SM CS 61 799)
Supply on the CS 61 799 circuit diagram: 2200 µF in the power unit, C50, C15, C92 and C95 on the board (Philips)
Electrolytic capacitors on the CS 61 799 board and modulator
Ref Value Philips part no. Where it connects (circuit diagrams) Rating
C15 4700 µF 4822 124 70316 Reservoir at the regulator inputs, after connector P4 Same part number as C876 (25 V) on the CS 75 068 board
C50 4.7 µF 5322 124 24104 In parallel with C15 Not printed
C95 10 µF Circuit diagram only Output of regulator VR1 (5 V, +1 rail) Not printed
C92 10 µF Circuit diagram only Output of regulator VR2 (5 V, +2 rail) Not printed
C42 47 µF 4822 124 20461 +2 supply of the PAL colour encoder IC29, with C79 (1 nF), through R8 (3 kΩ) Not printed
C14 1 µF 4822 124 20822 RESET input of the 8048, IC1, with the reset key through R44 (1 kΩ) Not printed
C131 100 µF Circuit diagram only Modulator video input P8-3 coupling Not printed
C120 1 µF 4822 124 20822 Modulator sound input P8-1 coupling Not printed
C101 10 µF Circuit diagram only Modulator +5 V decoupling after R101 Not printed
C118 10 µF Circuit diagram only Decoupling in the 559.25 MHz oscillator TS103 Not printed
C127 10 µF Circuit diagram only Decoupling in the sound oscillator TS104 Not printed

[2][3][1]

Where no rating is printed, read the one on the fitted part and use the same or higher. The rails on this board are 5 V after the regulators and about 14 V before them, from a 14 V DC power unit.[10][3]

Internal power supplies

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No circuit or parts list for the internal supplies of the G7000/22, /23 and /37 has been published. The one discussed on the Videopac / Odyssey2 forum is a switch-mode supply with a BUX84 transistor and a TDA2581 controller, and its secondary diodes D193 and D194 and fuse VL215 are named in the discussion.[5] Photograph the board, record each electrolytic's value, voltage and temperature rating before removing it, and keep the board's polarity markings. Treat the primary side as live mains.

Procedure

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  1. Unplug the console and the power unit from the mains.
  2. Open the case. Avoid flexing the keyboard foil tail, which cracks.[11]
  3. Photograph the board and note which manual matches it.
  4. Note the polarity of each electrolytic before removing it.
  5. Fit parts of the same capacitance and at least the same voltage rating. C876 or C15, the 4700 µF reservoir, is the largest part; check the diameter and lead spacing of the replacement against the board.
  6. For C607 to C611 or C101 to C131, open the modulator's shield and leave its coils and trimmers as they are.[7]
  7. Reassemble and make the checks below.

Post-recap checks

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Checks after recapping
Check Expected Source
Each regulator output to ground 5 V Circuit diagrams; owners' measurements[6]
IC678 pin 6 (CS 75 068 board) 4.433619 MHz; adjust C777 only if it is off Service manual CS 75 068, p. 2[7]
Collector of TS2 (CS 61 799 board) 17.734476 MHz; adjust C2 only if it is off Service manual CS 61 799, p. 2[12]
Television on UHF channel 32, cartridge fitted Game picture and sound Service manuals, specification[13]
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References

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  1. ↑ 1.0 1.1 1.2 1.3 1.4 1.5 1.6 Philips, Service Manual: Videopac Computer G7000/20/35/53, CS 75 068 (4822 727 13731), p. 5: electrical parts list (diodes D1 to D4 1N4001, transistors, capacitors C607 to C876 with values and ratings, R748 470 Ω, X693 17.73 MHz, fuses VL1 T160 mA and T140 mA and VL3 T4A, IC651 8048, IC652 8245, IC653 6810, logic IC654 to IC680, IC681 and IC682 L7805CV). Hosted as File:Philips Videopac G7000 Service Manual CS 75 068.pdf.
  2. ↑ 2.0 2.1 Philips, Service Manual: Videopac Computer G 7000, CS 61 799 (4822 727 11796), p. 6: parts list (D3 to D6 1N4001; TS1, TS2, TS102 to TS104; C2 2 to 11 pF, C14 1 µF, C15 4700 µF, C42 47 µF, C50 4.7 µF, C120 1 µF; IC1 8048/612191-1, IC2 8245, IC3 6810, IC29 612160-3, VR1 and VR2 LM340-5; X1 17.73 MHz). Hosted as File:Philips Videopac G7000 Service Manual CS 61 799.pdf.
  3. ↑ 3.0 3.1 3.2 3.3 3.4 Philips, Service Manual: Videopac Computer G 7000, CS 61 799 (4822 727 11796), pp. 3 and 5: circuit diagrams of the UHF modulator U100 (electrolytics C101, C118, C120, C127, C131) and the main board CS 61 802 (power supply with T1, D3 to D6, 2200 µF, P4, C50, C15, VR1 and VR2; crystal oscillator TS1 and TS2 with X1 and trimmer C2; 8048 IC1, 8245 IC2, 6810 IC3, PAL colour encoder IC29). Hosted as File:Philips Videopac G7000 Service Manual CS 61 799.pdf.
  4. ↑ 4.0 4.1 4.2 4.3 4.4 Philips, Service Manual: Videopac Computer G7000/20/35/53, CS 75 068 (4822 727 13731), pp. 7 and 8: circuit diagram (power supply CS 75 074 with T1, D1 to D4, C1, P4, C876, C816 and IC681/IC682; the 17.734476 MHz oscillator X693, C777 and IC680; hand controls P2 and P3 through 74LS365 buffers IC677 and IC658; keyboard P5 with decoder IC657 and encoder IC654; 8048 IC651; 8245 IC652; 6810 RAM IC653; PAL colour encoder IC679; RF modulator U100 on P6). Hosted as File:Philips Videopac G7000 Service Manual CS 75 068.pdf.
  5. ↑ 5.0 5.1 Videopac / Odyssey2 forum (videopac.nl), Hardware board, "G7000 Power Supply FAILURE", posts by AXEL72 and gertk, 31 January to 3 February 2018 (retrieved 2026-10-21): a G7000 with an internal switch-mode supply (BUX84, TDA2581) that buzzed and whose output rose without load after a switch was put in the 5 V line; gertk's advice to switch the mains side, his reading that the supply takes its feedback from the primary side (14 V through D192), and the parts to check (D193, D194, fuse VL215).
  6. ↑ 6.0 6.1 Videopac / Odyssey2 forum (videopac.nl), Hardware board, "G7000/00 - power questions", posts by gertk (8 and 18 November 2017), Rene_G7400 (9 November 2017), Janzl and Fleder (retrieved 2026-10-21): the external supply rated 10 V at 1.1 A; a 9 V 1 A stabilised adapter with the tip positive as a substitute; the plug is like a mono 3.5 mm jack; no useful picture without a cartridge; a dirty cartridge connector giving a garbled screen; the 7805 pinout, 9 to 15 V at the input and 5 V at the output, and finding the ground wire by resistance to the modulator case.
  7. ↑ 7.0 7.1 7.2 7.3 Philips, Service Manual: Videopac Computer G7000/20/35/53, CS 75 068 (4822 727 13731), p. 2: adjustments (clock frequency 4.433619 MHz set with C777 and measured at pin 6 of IC678; modulation depth set with R748; UHF channel 32 set at the factory, variable from channel 31 to 33 with L650, other U100 coils to be left alone). Hosted as File:Philips Videopac G7000 Service Manual CS 75 068.pdf.
  8. ↑ Philips, Service Manual: Videopac Computer G7000/20/35/53, CS 75 068 (4822 727 13731), p. 3: circuit diagram and board of the UHF modulator U100 (inputs P8-1 sound, P8-2 +5 V, P8-3 video; TS601 BF979 oscillator at 559.25 MHz; TS602 BF324 sound oscillator at 5.5 MHz, 6 MHz on the /35; TS603 MFE131; output at 564.75 MHz on /20 and /53, 565.25 MHz on /35; electrolytics C607 to C611). Hosted as File:Philips Videopac G7000 Service Manual CS 75 068.pdf.
  9. ↑ Videopac / Odyssey2 forum (videopac.nl), Hardware board, "G7000 and 14volts psu?", posts by mike76, scouter3d and Xuul, September and October 2022 (retrieved 2026-10-21): an original Philips supply labelled 10 V 1.1 A that reads almost 14 V with no load, which the replies say is normal for an unloaded supply.
  10. ↑ Philips, Service Manual: Videopac Computer G 7000, CS 61 799 (4822 727 11796), p. 1: specification (UHF channel 32 at 559.25 MHz, mains 220 V, 240 V British version, supply voltage 14 V DC at 0.8 A, 32 ICs, 5 transistors, 8 diodes). Hosted as File:Philips Videopac G7000 Service Manual CS 61 799.pdf.
  11. ↑ Videopac / Odyssey2 forum (videopac.nl), Hardware board, "Ribbon cable repair?", posts by drchuckradio and scouter3d, September 2022 (retrieved 2026-10-21): a damaged keyboard foil leaving the 0 to 7 keys dead; repairs with silver conductive paint, which may crack if the foil is bent again, or by moving the foil connector so the foil is not stressed when the case is opened.
  12. ↑ Philips, Service Manual: Videopac Computer G 7000, CS 61 799 (4822 727 11796), p. 2: adjustments (clock frequency 17.734476 MHz set with C2 and measured at the collector of TS2; modulation depth set with R7; UHF channel 32, variable from 31 to 33 with L105). Hosted as File:Philips Videopac G7000 Service Manual CS 61 799.pdf.
  13. ↑ Philips, Service Manual: Videopac Computer G7000/20/35/53, CS 75 068 (4822 727 13731), p. 1: specification (UHF channel 32 at 559.25 MHz, 75 Ω aerial impedance, mains 220 V, 240 V for the British version, supply voltage 10 V DC at 1.1 A, 32 ICs without the cartridge, 3 transistors, 8 diodes). Hosted as File:Philips Videopac G7000 Service Manual CS 75 068.pdf.


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