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Philips Videopac G7000 Troubleshooting Guide

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Philips Videopac G7000 repair method chart (SM CS 75 068)
Philips's repair method chart for a G7000 that gives no picture (service manual CS 75 068)

Philips's service manual CS 75 068 for the Philips Videopac G7000/20/35/53 has a fault-finding chart for a console with no picture and a page of oscillograms with their measuring points; manual CS 61 799 has the circuit diagram of another board. Below the chart, the checks follow the circuit diagrams and repairs that owners have reported on the Videopac / Odyssey2 forum.[1][2][3] Routine care and the three adjustments are on Philips Videopac G7000 General Maintenance. Hand control and cartridge faults common to the Odyssey² are also covered on Magnavox Odyssey² Troubleshooting Guide.

Behaviour that is not a fault

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  • Without a cartridge the console shows no useful picture, only garbage.[4][5]
  • Many consoles have no power switch; they are off only when the mains plug is pulled.[6]
  • An external power unit with nothing connected reads up to about 14 V, against its 10 V rating.[7]
  • The console transmits on UHF channel 32, which can be moved only between channels 31 and 33.[8]
  • Connecting a hand control while the console is on does no harm; a hand control is only five switches.[9]

Power faults

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Warning: the external power unit and the internal supplies of the /22, /23 and /37 carry mains voltage.

Power supply faults
Symptom Probable cause Action
Completely dead, external power unit No output from the unit: mains plug, fuse, transformer or bridge Measure the unit's DC output at its plug; check the primary fuse (T160 mA, or T140 mA on the /35) and the T4A fuse on the /35[10][11]
Unit output present, no 5 V on the board Connector P4, chokes S696 and S697, a shorted C876 or C816, or a regulator Measure across C876, then the input and output of IC681 and IC682[10][4]
One 5 V rail missing One regulator, or a short on its rail Disconnect the power board or lift the regulator's output and measure again[4]
Power unit buzzes loudly Loose transformer laminations Glue the laminations, or replace the unit[11]
Internal supply whines and its output creeps up Switch-mode supply without load or with a fault in its output stage Switch on the mains side only; check the output diodes and the fuse; or replace the supply with a 5 V adapter of at least 1.5 A[12][13][14]
Picture flickers and the console seems to reset every half second Suspected by one owner to be the built-in supply Measure the 5 V reaching the main board with the console running[13][15]
  • On the G7000/20/35/53 the power unit's output enters the board at P4: P4-1 positive, P4-3 negative. A reversed supply is not blocked by any diode on the board.[16]
  • Each 7805-type regulator should have 9 to 15 V between its ground and input pins and 5 V at its output.[4] One dead console had 4.85 V from its regulators and still showed no activity on the board, so a correct supply does not rule out a fault elsewhere.[17]
  • The main board of a console with an internal supply takes 5 V. One owner first fed 10 to 12 V into those wires from a current-limited bench supply, then 5 V, and the console still gave no picture.[14] Set a bench supply to 5 V before connecting it.

No picture

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Philips's repair method

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The chart in service manual CS 75 068 starts from a television that shows no game picture and works through the clock chain with an oscilloscope. Each step checks one oscillogram from the manual's oscillogram page and branches on whether it is correct.[1][2]

  1. Check oscillogram 5 at pin 2 of the 8048, IC651: about 4 V peak to peak at about 6 MHz (5.91 MHz).
  2. If oscillogram 5 is wrong, check oscillogram 1 at pin 12 of IC661d: 2.5 V peak to peak at 17 MHz. If that is correct, check IC662a, IC662b and IC661d, which divide the clock by three. If it is wrong, check the oscillator IC680 and the crystal X693.
  3. If oscillogram 5 is correct, check oscillogram 12 at pin 1 of the 8245, IC652: 3.5 V peak to peak at about 3.5 MHz. If it is wrong, check IC663, IC674 and IC661, which divide the clock by five.
  4. If oscillogram 12 is correct, check oscillogram 18 at pin 6 of IC652: 4 V peak to peak at 50 Hz. If it is wrong, check IC652 and IC659.
  5. If oscillogram 18 is correct, check oscillogram 32 at pin 5 of the colour encoder IC679. If it is wrong, check IC679. If it is correct, check the modulator U100.

"Check" in the chart means measuring voltages and resistances around the named parts.[1]

Owners' repairs

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  • The PAL colour encoder IC679, a TEA1002, is the part owners most often replace for a G7000 with sound but no picture; one owner has replaced two.[18] Another console had a black screen from a faulty encoder and gave a picture through an RGB adapter that bypasses it.[19]
  • For a rev. 22 board with no video and no sound, even through a composite modification, the suggestion was to replace IC661, IC662 and IC679.[20]
  • A stable black picture on channel 32 with 5.2 V on the board led to the advice to try another 8048 first.[21]
  • A G7000/00 with no picture worked again after the large chips were swapped back and the cartridge socket cleaned; its CPU clock measured 5.8 MHz.[22]
  • One owner found weak signals at the encoder's R−Y, B−Y and blanking inputs and nothing at its output, pin 5; the reply named the encoder as a part that often fails.[18]

The 8048 holds the BIOS in mask ROM, so a new blank 8048 will not run. Use one from another console or an 8748 programmed with the BIOS dump.[5][23][24] MAME uses the same BIOS image for the G7000 and the Odyssey², and different ones for the French C52 and for the G7400.[25]

RF modulator

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U100 takes video at P8-3, +5 V at P8-2 and sound at P8-1.[26] On the board side its video comes from IC679 through R748, and oscillogram 31 at P6-3 shows 0.5 V.[10][2] If the video reaches U100 but the television shows nothing, try a known-good modulator or a composite video modification before touching the coils; Philips allows only L650 to be turned, to move between channels 31 and 33.[8][27] The G7000/00 modulator has three connections and the G7000/20 one four, so they are not interchangeable without rewiring.[22]

Wrong characters or graphics

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Picture faults with the game running
Symptom Probable cause Action
Garbled screen that changes when the cartridge is reseated Dirty cartridge connector Clean the connector and the cartridge contacts[4]
Game starts but shows wrong characters and miscounts 6810 RAM (IC653) Fit another 6810; an MCM6810 failure was cured with a Fairchild 6810[28]
Black screen, sound present PAL encoder IC679, or the 8245 Follow the repair method above; replace IC679[18][1]
Colours wrong or missing 4.43 MHz reference off frequency, or IC679 Measure 4.433619 MHz at pin 6 of IC678 and adjust C777 only if it is off[8]

Hand control faults

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Each hand control line has a 3.3 kΩ pull-up and a 1 nF capacitor on the board and goes into a 74LS365 buffer, IC677 for one port and IC658 for the other on the CS 75 068 board.[10]

  • A direction that reads as always on, on one port only, has been traced to that port's 74LS365. With the hand control unplugged, measure the input pin: a line held low with no short on the board means a damaged buffer.[9]
  • A direction that only works now and then on a wired-in black hand control: measure the line's resistance with the stick held over. Readings around 2 kΩ were too high for the buffer to see a low, and the worn membrane board had to be replaced.[29]
  • A plug-in hand control that loses one direction may simply be loose in its D-sub socket.[11]

The plug-in socket pinout is 1 ground, 2 action, 3 left, 4 down, 5 right and 6 up.[9] Cleaning the switch contacts is described on Magnavox Odyssey² General Maintenance#Hand controls.

Keyboard faults

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The keyboard matrix has six rows driven by the 74LS156 decoder IC657 from the 8048's port 2, and eight columns read through the encoder IC654. The circuit diagram marks IC654 as a 74LS148, as does the CS 61 799 parts list for its IC4; the CS 75 068 parts list prints 74LS168. RESET is a separate key on P5-15 and P5-16.[10][30][31]

  • A group of keys dead together, such as 0 to 7, has been a break in the keyboard foil tail.[32]
  • If the foil tests good, follow the dead row or column from P5 to IC657 or IC654.[10]

Sound faults

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The 8245 generates the sound at its pin 27, and it reaches the modulator's sound input P8-1, where the coupling capacitor C609 (1 µF) feeds the sound oscillator TS602.[10][26] With picture but no sound, check the television's volume and fine tuning first, then the signal at IC652 pin 27 and at P8-1. The British /35 modulator uses a 6 MHz sound carrier and the /20 and /53 one 5.5 MHz.[26]

Test points

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G7000/20/35/53 test points (service manual CS 75 068)
Point Signal Expected Oscillogram
IC681 and IC682 outputs +A and +B supply 5 V Circuit diagram
IC661 pin 12 Master clock 17.734 MHz, 2.5 V peak to peak 1
IC662 pin 9, IC651 pin 2 8048 clock 5.91 MHz, about 4 V peak to peak 5
IC674 pin 6, IC652 pin 1 8245 clock 3.54 MHz, about 3.5 V peak to peak 12
IC660 pin 5 Colour clock 8.86 MHz 25
IC678 pin 6 Colour reference 4.433619 MHz; adjust with C777 26
IC661 pin 6 Colour reference 4.43 MHz 27
IC652 pin 6 Vertical timing 50 Hz, 4 V peak to peak 18
IC652 pin 5 Line timing 64 µs period 20
IC679 pin 5 Encoder output As oscillogram 32 32
P6-3 Video into U100 0.5 V 31

[2][1][8][10]

On the board of manual CS 61 799 the clock is set at the collector of TS2 to 17.734476 MHz, and the supply regulators are VR1 and VR2.[33][3]

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References

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  1. ↑ 1.0 1.1 1.2 1.3 1.4 Philips, Service Manual: Videopac Computer G7000/20/35/53, CS 75 068 (4822 727 13731), p. 11: repair method chart 18344B12 for a console that gives no television picture. Hosted as File:Philips Videopac G7000 Service Manual CS 75 068.pdf.
  2. ↑ 2.0 2.1 2.2 2.3 Philips, Service Manual: Videopac Computer G7000/20/35/53, CS 75 068 (4822 727 13731), p. 4: oscillograms 1 to 32 (the 17.734 MHz master clock at IC661 pin 12, divided by 3 to 5.91 MHz at IC662 pin 9 and by 5 to 3.54 MHz at IC674 pin 6; 8.86 MHz at IC660 pin 5 and 4.43 MHz at IC678 and IC661 pin 6; video timing at IC652; 0.5 V video at P6-3). Hosted as File:Philips Videopac G7000 Service Manual CS 75 068.pdf.
  3. ↑ 3.0 3.1 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 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.
  5. ↑ 5.0 5.1 Old Crap Vintage Computing, "Philips Videopac G7000", 8 November 2020 (retrieved 2026-10-21): photographs of a G7000/22 (rating plate 220 V 50 Hz 7 W, made in France) with its internal power supply board, modulator and main board; the 8048 holds its program in mask ROM and can be replaced by an 8748; without a cartridge the console shows garbage.
  6. ↑ Philips, Videopac Computer G7000: Instructions for Use, English notes: a Videopac contains sophisticated electronics and must be treated carefully; replace a Videopac in its box when not in use; the console is switched off only when the mains plug is removed; return the cartridge and console to the dealer if a cartridge does not work; a picture displayed for several hours may damage the television screen. Hosted as File:Philips Videopac G7000 Instructions for Use.pdf.
  7. ↑ 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.
  8. ↑ 8.0 8.1 8.2 8.3 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.
  9. ↑ 9.0 9.1 9.2 Videopac / Odyssey2 forum (videopac.nl), Hardware board, "G7000 joystick always "up" after connecting joystick "live"", posts by emuola, Rene_G7400 (19 September 2014), Seob and gertk (22 September 2014) (retrieved 2026-10-21): a G7000 whose hand control read as always up after a socket pin was pushed in; Rene_G7400 agrees the 74LS365 for that port should be replaced and says connecting a hand control live does no harm; gertk's method for checking the input voltage and replacing the chip; the plug-in socket pinout (1 ground, 2 fire, 3 left, 4 down, 5 right, 6 up).
  10. ↑ 10.0 10.1 10.2 10.3 10.4 10.5 10.6 10.7 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.
  11. ↑ 11.0 11.1 11.2 Videopac / Odyssey2 forum (videopac.nl), Hardware board, "Noisy power supply - wired wrong to hide it?", posts by Juicy and Xuul, August and September 2023 (retrieved 2026-10-21): a G7000 whose external transformer buzzed loudly; the laminations had lifted and were glued, after which the supply was silent; Xuul asks whether it is a /21 with a 160 mA fuse; plug-in hand controls that fit loosely in their D-sub sockets.
  12. ↑ 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).
  13. ↑ 13.0 13.1 Videopac / Odyssey2 forum (videopac.nl), Hardware board, "Videopac G7000 problem. Power Supply?", posts by Rene_G7400 (31 December 2016), VideopacBelgium (17 January 2021) and others (retrieved 2026-10-21): a G7000 with a built-in supply that flickered and reset; Rene_G7400's advice that an internal switch-mode supply can be replaced by a 5 V adapter of at least 1.5 A.
  14. ↑ 14.0 14.1 Videopac / Odyssey2 forum (videopac.nl), Hardware board, "Troubleshooting G7000 with noisy power supply", posts by jomag, June to August 2021 (retrieved 2026-10-21): a G7000 with a built-in supply that whined and whose output crept up; the main board takes 5 V; the G7000/22 and /23 boards differ from the G7000/20/35/53 service manual; three socketed chips (CPU, memory, graphics) swapped between consoles.
  15. ↑ Videopac / Odyssey2 forum (videopac.nl), Hardware board, "My G7000 has failed after nearly 40 years!", posts by David Norwood and VideopacBelgium, January 2020 (retrieved 2026-10-21): a G7000 with a built-in supply that shows only a dark green screen; VideopacBelgium's advice to check the 5 V from the power supply to the main board, with a warning that parts of the supply carry high voltages.
  16. ↑ Videopac / Odyssey2 forum (videopac.nl), Hardware board, "G7000 Power supply", posts by isifloh and Rene_G7400, 20 to 31 May 2015 (retrieved 2026-10-21): a G7000/20 with an external supply; P4-1 is positive and P4-3 negative; there is no reverse polarity protection; isifloh fitted a bridge rectifier ahead of a standard supply.
  17. ↑ mayermakes, "You remember Atari and Intellivision..but do you remember the Philips G7000?", element14 Community, 27 September 2023 (retrieved 2026-10-21): a G7000 with wired-in hand controls and an external power adapter with a small proprietary connector; two LM7805 regulators on the board giving 4.85 V; no video signal and no activity on the board.
  18. ↑ 18.0 18.1 18.2 Videopac / Odyssey2 forum (videopac.nl), Hardware board, "Videopac G7000 with no video output", posts by CRG (3 November 2020) and Xuul (17 September 2023) (retrieved 2026-10-21): a G7000 that played sound but gave no picture, with weak signals at the PAL encoder; Xuul names the PAL encoder IC679, a TEA1002, as a chip that fails often and has replaced two.
  19. ↑ Videopac / Odyssey2 forum (videopac.nl), Hardware board, "G7000 black screen and other trouble", posts by emilen72 and Xuul, April 2024 (retrieved 2026-10-21): a PAL G7000 with a black screen caused by the PAL encoder chip, which gave a picture once an RGB adapter was fitted.
  20. ↑ Videopac / Odyssey2 forum (videopac.nl), Hardware board, "G7000: no video, no sound", posts by Stefan (10 January 2025) and Xuul (8 February 2025) (retrieved 2026-10-21): a G7000 rev. 22 with a working internal supply and no picture or sound even after a composite modification; the CPU and graphics chip worked in another console; Xuul suggests replacing IC661, IC662 and IC679.
  21. ↑ Videopac / Odyssey2 forum (videopac.nl), Hardware board, "G7000 from Ebay ... black screen", posts by Mobeyhead and VideopacBelgium, 9 August 2018 (retrieved 2026-10-21): a G7000 with a stable but black picture on channel 32 and about 5.2 V on the main board; VideopacBelgium's advice to replace the 8048 first.
  22. ↑ 22.0 22.1 Videopac / Odyssey2 forum (videopac.nl), Hardware board, "G7000/00 (no pictures): special measuring points", posts by g7000Mikel, May 2019 (retrieved 2026-10-21): a G7000/00 with plug-in silver hand controls, an external supply and a three-terminal modulator (four on the G7000/20); the CPU clock measured at 5.8 MHz; the console worked again after the large chips were reseated and the cartridge socket cleaned.
  23. ↑ Videopac / Odyssey2 forum (videopac.nl), Hardware board, "problems with replacement chips P8048H on the videopac g7400", posts by maeloterkim, manopac and gertk, March and April 2023 (retrieved 2026-10-21): generic P8048H chips do not work as replacements because the 8048 contains the console's ROM; an 8748 programmed with the BIOS is the alternative.
  24. ↑ Videopac / Odyssey2 forum (videopac.nl), Hardware board, "Videopac G7000 - defect CPU", posts by Vader_CH and TedFoolery, January 2021 (retrieved 2026-10-21): a G7000 with a damaged CPU; an 8749H programmed with the 8048 contents did not work for the poster; TedFoolery posts the Odyssey² and G7400 BIOS files used by emulators.
  25. ↑ MAME source, src/mame/philips/odyssey2.cpp, hardware notes by Peter Trauner, Wilbert Pol and hap (retrieved 2026-10-21): the Videopac consoles and their badged versions, the 8245 on PAL consoles in place of the 8244, 128 bytes of 6810 RAM, the G7000 crystal at 17.734476 MHz with the 8048 clocked at a third and the 8245 at a fifth of it, and the extra TTL on the Videopac board for the 8245's vertical blanking interrupt; the same BIOS dump (o2bios.rom) is loaded for the Videopac G7000 and the Odyssey², and separate dumps for the French C52 and the G7400.
  26. ↑ 26.0 26.1 26.2 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.
  27. ↑ Videopac / Odyssey2 forum (videopac.nl), Hardware board, "Does anyone in the UK have a spare RF box/lead for G7000?", posts by David Norwood and others, January to May 2020 (retrieved 2026-10-21): a damaged RF lead; a modulator box from a donor G7000 gave a poorer picture than it had in its own console.
  28. ↑ Videopac / Odyssey2 forum (videopac.nl), Hardware board, "G7000/53 works with mistakes", posts by Markus_64, August 2019 (retrieved 2026-10-21): a G7000/53 that started but showed wrong characters and counters, cured by replacing the 6810 RAM (an MCM6810) with a Fairchild 6810.
  29. ↑ Videopac / Odyssey2 forum (videopac.nl), Hardware board, "G7000 joystick repair possible", posts by Jon (24 December 2025) and Xuul (24 January 2026) (retrieved 2026-10-21): a G7000/37 whose switch-mode supply Jon had repaired; the wired-in black hand controls contain a membrane, and the resistance of their lines measured 30 Ω to about 2 kΩ, too high for the buffer input to see a low; Xuul replaced the whole hand control board after cleaning failed.
  30. ↑ 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.
  31. ↑ 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.
  32. ↑ 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.
  33. ↑ 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.


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