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Grandstand Colour Programmable SD070 Capacitor Replacement Guide

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Grandstand Colour Programmable SD070 (4)
The SD070's main board from the solder side, in the upper case, with "SD-070", "REV F" and "11-00110-13" in the copper and the serial label 46. The electrolytic capacitors are on the other side, which has not been photographed on a Grandstand set.

The Grandstand Colour Programmable SD070 is a PC-50x cartridge console built in Hong Kong on Soundic's SD-070 design and sold by Grandstand around 1980; the photographed set carries the batch label 08-80-02.[1][2] Its main board carries the power input, the RF modulator, the switches and the sockets, and the game chip sits in the cartridge.[3][4] No parts list, schematic or service manual for the SD070 has been published. The component side of a Grandstand board has not been photographed either, so no capacitor value on this console can be read from any published source. What is known is where the electrolytics sit, from photographs of a Hanimex TVG 070C built on a main board with the same number, and what General Instrument's own circuit for the cartridge chip needs from the supply. Both are set out below, with how to read, record and replace the parts on your own board.

Opening the case is on Grandstand Colour Programmable SD070 General Maintenance; symptoms are on Grandstand Colour Programmable SD070 Troubleshooting Guide.

Where the electrolytics are

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Electrolytic capacitors on an SD-070 main board 11-00110-13 REV F (photographed in a Hanimex TVG 070C)
Position (component side, slide switches at the top left, cartridge connector at the right) Capacitance Voltage Sleeve Source
Left end, above the left joystick socket and left of the RF board Not legible Not legible Dark blue; the largest on the board [3]
Beside it, towards the slide switches Not legible Not legible White [3]
Top left corner, beside a transistor (two parts) Not legible Not legible One dark, one light blue [3]
Between the second and third slide switches Not legible Not legible Silver-grey with a white top [3]
Top centre, beside the flat cable to the button board Not legible Not legible Blue [3]
Below the volume slider Not legible Not legible Small, light blue [3]
Right end, upper corner (two parts) Not legible Not legible One with a white top, one black [3]
RF board 11-00081-00, at its corner nearest the left end Not legible Not legible A small grey cylinder with a dark top; check that it is an electrolytic [3]

Read from photographs 008 and 009 of the Hanimex TVG 070C teardown on The Liberator (1600 × 1200 pixels), examined at full size. At that size each capacitor is only a few dozen pixels across and none of the printing can be read.[3] No capacitor values have been published for the SD070, and none can be read from any published photograph. The table gives positions only. Read each value from the part in front of you.

The Hanimex board in those photographs is the same board as the Grandstand's: both carry 11-00110-13 REV F, and their solder sides look the same.[3][1] The two consoles are not identical: the Hanimex works on VHF channel 1 to the 625-B PAL standard and the Grandstand on UHF channel 36 to the UK's System I, so expect differences in the RF section.[3][1] Not every SD-070 board is this one, either. A Hanimex TVG 070C photographed by the collector who owns the Grandstand set has an earlier board, marked SD-070C and Rev. A, with a different layout.[5] Check the number on the solder side of your board before using the table.

The cartridge

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Grandstand Colour Programmable SD070 (2)
The Supersportic PC-501 cartridge board: the AY-3-8610 with date code 8034, two trimmers (one marked 500K), green film capacitors and one ceramic disc. There are no electrolytics.

The Supersportic cartridge (PC-501, REV B) has no electrolytic capacitors. Its board carries the AY-3-8610 game chip, two trimmers for the bat positions, green film capacitors and a ceramic disc.[1][2] It needs no recapping. Clean its edge contacts instead.

What the capacitors do on this console

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No schematic of the SD070 has been traced, so the job of each part on its board is not known. These points are established:

  • The console runs from six UM-2 (C) cells or a 9 V DC adaptor rated 200 mA; the Grandstand's label shows a tip-positive plug.[1] The Hanimex TVG 070C's label shows the opposite polarity, tip negative, and its owner notes that the Hanimex adaptor does not suit the original Soundic console.[3][5] Check an adaptor's polarity against the console's own label before plugging it in.
  • The cartridge chip, an AY-3-8610 in the Supersportic, is specified by GI at +6 to +7 V, drawing at most 60 mA at +7 V.[6] The cartridge board carries no regulator, only the chip, two trimmers, resistors and capacitors, so the chip's supply comes from the console's main board through the edge connector.[1]
  • GI's own full-colour circuit for the AY-3-8610 shows one way to build such a supply: a transistor regulator with a 6.8 V zener diode and a 150 Ω resistor, fed from a 9 V 150 mA battery or adaptor, with a 2.2 µF capacitor on its input and another on its output. The same circuit couples the video through a 22 µF capacitor and decouples the modulator feed with 0.1 µF capacitors.[6] These are GI's values for GI's circuit, not readings from an SD070, but they show the kind of part to expect near the supply and the RF board.
  • The console has its own 8 Ω speaker with a volume slider.[3][2] In GI's circuit the sound output drives the speaker through a 2N3906 transistor and 47 Ω.[6]

Signs of trouble

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The photographed Grandstand set works,[2] and no capacitor failure in an SD070 turned up in the sources searched.

Reading and recording your own board

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  1. Before removing anything, read the board number on the solder side (11-00110-13 REV F on the photographed Grandstand set) and note it with your records.[1]
  2. Photograph the component side square-on in good light, including the RF board at the front.
  3. For each electrolytic, write down its position, the capacitance, the voltage, the maker, the diameter and height, and which side carries the negative stripe. Note which ones sit near the DC socket and the RF board.
  4. Where the printing faces away, turn the part gently with tweezers or use a mirror.
  5. Measure each removed part with a capacitance or ESR meter.
  6. Keep the record with your photographs. A full list for the SD070 has never been published, and a record from a real board fills that gap.

Replacing the capacitors on the SD070

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  1. Take out the cartridge and the six cells, and unplug the adaptor and both joysticks.
  2. Turn the console over and remove the four screws in the lower case; one is inside the battery compartment.[2]
  3. Lift the lower case away slowly. The speaker is screwed to it and the battery contacts are wired to the board, so lay the two halves side by side.[2][1]
  4. The main board is now solder side up in the upper case, held by three screws and two clips.[2] Photograph the wiring, remove the screws, release the clips and lift the board out, watching the flat cable to the button board, the RF lead and the DIN sockets at the ends of the board.[3]
  5. Work on one capacitor at a time: read and record it, desolder it with a pump or braid, clean the holes with isopropyl alcohol, and fit a new part of the same capacitance and the same or higher voltage, rated 105 °C, with the same lead spacing and polarity.
  6. Do not move the coils or the screened can on the RF board while you work near it; they are factory adjustments.[3] The SOUND CARRIER ADJ hole in the base reaches another adjustment; leave it alone.[1]
  7. Refit the board with its three screws and two clips, check that no wire is trapped, and refit the lower case.
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  • Temperature-controlled iron, a desoldering pump or wick, flux and isopropyl alcohol; a small mirror for printing that faces away.
  • Multimeter, and a capacitance or ESR meter for the parts that come out.
  • Radial electrolytics rated 105 °C from a current maker (Nichicon, Panasonic, Rubycon or similar), matched to what your SD070 board carries.
  • A current-limited bench supply, set to 9 V with the polarity of your console's label. See also Recommended Tools.

Checks after recapping

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After recapping an SD070
Check Expected Source
Supply at the DC-9V socket or the cells 9 V DC, with the polarity of the console's own label (tip positive on the Grandstand) [1]
Supply current Within the label's 200 mA; the AY-3-8610 alone draws at most 60 mA at +7 V [1][6]
AY-3-8610 pin 16 (VCC) to pin 1 (VSS), on the cartridge board +6 to +7 V [6]
Picture Colour picture on UHF channel 36, PAL System I, with the cartridge's games selected from buttons 1 to 10 [1][2]
Sound From the internal speaker, varying with the VOLUME slider; on the television only with a System I set [2]
Controls Both joysticks move their bats in both directions; SERVE/FIRE buttons, RESET and buttons 1 to 10 respond [1][6]
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References

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  1. ↑ 1.00 1.01 1.02 1.03 1.04 1.05 1.06 1.07 1.08 1.09 1.10 1.11 1.12 1.13 1.14 Photographs File:Grandstand Colour Programmable SD070 (2).jpg, File:Grandstand Colour Programmable SD070 (4).jpg, File:Grandstand Colour Programmable SD070 (5).jpg, File:Grandstand Colour Programmable SD070 (6).jpg and File:Grandstand Colour Programmable SD070 (12).jpg (José Antonio Ortigueira Amor, CC BY 4.0, from Wikimedia Commons), examined at full resolution. Base label: "UHF CH-36 / 625-I PAL System / POWER SOURCE: Use 6x1.5V UM-2 batteries or AC adaptor 9V DC 200mA", with a plug drawing marked minus on the sleeve and plus on the tip; "SOUND CARRIER ADJ" label; "BATCH NO. 08-80-02". Opened console: the main board solder side up in the upper case, marked SD-070, REV F and 11-00110-13, serial label 46; speaker and battery tube in the lower case, wired to the board. Panel: SERVE (AUTO/MANU), TEAM L, TEAM R, SPEED, POWER, VOLUME slider, RESET and buttons 1 to 10. Cartridge board: "PC-501", "REV B", a General Instrument AY-3-8610 with date code 8034 as the only IC, two trimmers (one marked 500K), green film capacitors and one ceramic disc, and no electrolytic capacitors.
  2. ↑ 2.0 2.1 2.2 2.3 2.4 2.5 2.6 2.7 2.8 José Antonio Ortigueira Amor, "Consola Grandstand Colour Programmable (Model SD 070) (Video Sport Centre) (Endorsed by Kevin Keegan) (1980)", Retro Ordenadores Orty (collector's blog, in Spanish), March 2026 (retrieved 2026-10-19). The owner's description: a late version of Soundic's SD-070C, made in 1980 (batch 08-80-02, unit number 46) with a much newer REV F board; PAL System I picture, so no sound on continental PAL G sets; internal speaker with volume control; 9 V DC centre-positive socket and RF lead (UHF channel 36) at the rear; six LR14 cells; four screws hold the lower case, one inside the battery compartment; three screws and two clips hold the main board to the upper case; the speaker is screwed to the lower case; board marked 11-00110-13, REV F, SD-070; Supersportic PC-501 cartridge (11-40140-02, REV B) with the AY-3-8610 (8034) as its only IC; the console works correctly. The blog's two board photographs show the solder side only.
  3. ↑ 3.00 3.01 3.02 3.03 3.04 3.05 3.06 3.07 3.08 3.09 3.10 3.11 3.12 3.13 3.14 3.15 3.16 Avon Fox, "Hanimex TVG 070C TV Game-Programmable Rev F PAL", The Liberator (collector's site, photographs not freely licensed; retrieved 2026-10-19). Fifteen photographs of a Hanimex TVG 070C taken apart, examined at full size (1600 × 1200). Base label "HANIMEX MODEL: TVG 070C / VHF CH-1 / 625-B PAL system / ... AC adaptor 9V DC 200mA" with a plug drawing marked plus on the sleeve and minus on the tip. Photographs 007 and 011: solder side marked "11-00110-13" and "REV F", with "SD-070" printed near the flat-cable pads in 007. Photograph 008: component side with five slide switches, volume slider, blue cartridge edge connector, a 14-pin and a 16-pin IC, the RF modulator board (11-00081-00) with three adjustable coils and a screened can labelled CE-208E1, DIN sockets at both ends and at the rear, a flat cable to the button board, and the electrolytic capacitors listed in the table, whose printing cannot be read at this size. Photograph 009: close-up of the RF board. The text says the game circuits are in the cartridges and the sound comes from an 8 Ω speaker with a volume control.
  4. ↑ Pong-Story, "PC-50x cartridges" (retrieved 2026-10-19). Each cartridge contains a single General Instrument chip which holds most of the game circuits, so that "the console is more an interface than a real videogame system"; the cartridges fit many Asian-made consoles sold in Europe under different names.
  5. ↑ 5.0 5.1 José Antonio Ortigueira Amor, "Consola Hanimex TVG 070C Programmierbares (Soundic SD-070C) (1978)", Retro Ordenadores Orty (collector's blog, in Spanish), updated entry (retrieved 2026-10-19). A Hanimex TVG 070C sold in Germany, made by Soundic: 9 V DC socket wired centre negative, which the owner says makes the Hanimex adaptor incompatible with the original Soundic console (centre positive); four case screws, one in the battery compartment; board held by three screws. The board photographs, examined at full size, show an earlier layout with the cartridge connector along one edge, marked "SD-070C" and "Rev. A" on the solder side; the capacitor markings on its component side cannot be read.
  6. ↑ 6.0 6.1 6.2 6.3 6.4 6.5 General Instrument Corporation, GIMINI TV Game Circuits, January 1978, pp. 26-29, PDF hosted by Pong-Story (retrieved 2026-10-19). AY-3-8610 and AY-3-8610-1 ("Superstar"): pin 1 VSS, pin 16 VCC; standard conditions VCC +6 to +7 V; -0.2 to +12 V maximum on any pin; power supply current 60 mA maximum at +7 V; clock 3.579545 MHz; two-axis joystick inputs. System Diagram 2 (full colour implementation using the AY-3-8615, p. 27): "BATTERY OR AC ADAPTOR 9V 150mA" feeding an ON/OFF switch and a transistor regulator with a 6.8 V zener and 150 Ω, with 2.2 µF capacitors on its input and output and 0.01 µF beside the switch; 22 µF coupling the video to a 2N3904 stage; 0.1 µF capacitors and 22 Ω at the feed to an Astec UM1082 modulator; joystick inputs with 100 kΩ potentiometers, 82 kΩ, 0.22 µF and 1000 pF; the 8 Ω speaker driven through a 2N3906 and 47 Ω.


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