Jump to content

Grandstand Universal Mains Adaptor

From RetroTechCollection
Grandstand Universal Mains Adaptor
Grandstand Universal Mains Adaptor plug drawing
Plugging the adaptor lead into a game, from the "Adaptor Socket" section of Grandstand's Thomas the Tank Engine instruction book. No freely licensed photograph of the adaptor has been found
Manufacturer Sold by Adam Imports Ltd, Harrogate, under the Grandstand name; maker not known
Type Mains adaptor (battery eliminator) for electronic games
Release date Early 1980s; named in the Grandstand leaflets for games the Handheld Museum dates from 1981 (Astro Wars) to 1984 (Thomas the Tank Engine)[1][2]
Compatible Grandstand Astro Wars, Grandstand Crazy Monster, Grandstand Firefox F-7, Grandstand Star Force, BMX Flyer and Thomas the Tank Engine (see Grandstand Handheld and Pocket Games)
Model UGT[3]
Connectivity One output lead ending in a four-way cross-shaped plug carrying four jack plugs[3][4]
Power 240 V AC in; 6-9 V DC, 1.5 VA out (collector's reading)[3]

The Grandstand Universal Mains Adaptor (model UGT) is the 240 V mains adaptor that Adam Imports sold under its Grandstand name for running its battery-powered electronic games from the mains. It has one switch, which reverses the polarity of the output and also turns the output off.[3] Every Grandstand leaflet found for its Epoch-made tabletop games and its Tomy-made colour LCD games, six in all, names it as the way to run the game from the mains and says to set the switch to negative. None of them gives a voltage.[5][6][7][8][9][4]

The same games were sold in other countries with the makers' own adaptor ratings: 6 V DC for the Epoch games and 7.5 V DC for the Tomy ones, with the centre pin negative in both cases.[10][11] Grandstand's TV games differ from the tabletops: they run on 9 V, and the Colour Programmable SD070's label asks for the tip of the plug positive.[12] An owner's write-ups describe the 3600 Mk II and 4600 as centre positive as well, and the TV Game 2000 as centre negative (see below).

No instruction sheet or service information for the adaptor itself has been found. The Thomas the Tank Engine leaflet tells owners to read "the instructions supplied with the adaptor", so one existed.[4]

Description

[edit | edit source]

The Handheld Museum, a collector's site, lists the adaptor as model UGT, "sold by Grandstand in England/U.K. for their handheld/tabletop games" and made for the 240 V supply. Its entry says the switch toggles the polarity and turns the output off completely, and gives the output as "6-9v DC at 1.5vA". The same entry adds the collector's own view that "100-200 mA adapters will run these games".[3]

The museum's photograph shows a cream box-shaped case with a silver label reading "GRANDSTAND universal mains adaptor FOR GAMES AND TOYS" and the double-insulation symbol (a square within a square). A single output lead ends in a cross-shaped connector carrying four jack plugs of different sizes. The box reads "Grandstand Leisure Products universal mains adaptor, suitable for Electronic Games and Toys". The rating lines on the label are too small in that photograph to read reliably.[3] The Thomas the Tank Engine leaflet calls the connector a "Universal 4-way jack plug" and tells the owner to select the plug that fits the game's socket; the BMX Flyer leaflet warns that "the universal jack plug is different to that illustrated".[4][9]

Voltage settings

[edit | edit source]

No source seen documents a voltage selector. The only control described is the polarity and off switch.[3] The "6-9 V" figure is the collector's reading, and the entry does not say whether it is a range the user can select or the output of an unregulated adaptor varying with load. A rating of 1.5 VA works out at 250 mA at 6 V, or about 170 mA at 9 V.

What the Grandstand leaflets say

[edit | edit source]
Mains adaptor instructions in the Grandstand leaflets
Game Made by Batteries named Adaptor instruction
Astro Wars Epoch Four Duracell MN1400 (C) Grandstand Universal Mains Adaptor (not included); "Set polarity switch to negative - polarity"[5]
Crazy Monster Epoch Four Duracell MN 1400 (C) As Astro Wars[6]
Firefox F-7 Epoch Four Duracell MN1400 (C) As Astro Wars[7]
Star Force Epoch Four Duracell MN1400 (C) As Astro Wars[8]
BMX Flyer Tomy Four Duracell MN1400 alkaline (C) "Select negative polarity on the adaptor polarity switch"; "Using the wrong adaptor could damage the game"; disconnect the adaptor from the mains when not in use[9]
Thomas the Tank Engine Tomy Four Duracell MN1500 alkaline (AA) Select the plug on the 4-way jack plug; "Select negative polarity on the adaptor polarity switch"; "Using the wrong adaptor could damage the game"; disconnect the adaptor from the mains when not in use[4]

No Grandstand leaflet was found for Invader From Space, Munchman, Tron, The Big Game Soccer, Caveman, Scramble or Cosmic Invader, so it is not known from a leaflet whether Grandstand recommended the adaptor for them. For Invader From Space, the Victoria and Albert Museum's record of a boxed Grandstand example transcribes the box: four AA batteries, and it "Can be operated from the mains with a Grandstand Universal Mains Adaptor (optional extra)".[13] The makers' own leaflets cover several of them (below).

Why the leaflets say "negative"

[edit | edit source]

The Grandstand leaflets name a polarity setting but do not say which contact of the plug it refers to. The makers' leaflets for the same hardware do, and all of them put the centre pin negative:

  • Epoch's leaflet for Galaxy II, the game Grandstand sold as Astro Wars, gives "6-Volts DC, 250~300 ma" with the polarity symbol drawn positive on the outer ring and negative on the centre dot.[10][14]
  • Tomy's leaflets for Pac Man (Grandstand's Munchman), Tron and Caveman all give "Tip (Center) Polarity: Negative".[11][15][16]
  • Radio Shack's leaflet for Astro Thunder, the same Epoch game as Firefox F-7, tells the owner to take Radio Shack's own switchable adaptor, "Select the 6V range" and "set the center tip negative".[17][18]

Radio Shack's instruction for a switchable adaptor on the same game is the closest documented parallel to Grandstand's, so the "negative" setting is best read as centre (tip) negative. The adaptor's own instruction sheet would settle it; until one turns up, check the plug with a meter before connecting it to a game (see below).

The switch lets one adaptor serve equipment wired either way, and Grandstand's own range needed both: centre negative for the tabletop and colour LCD games, tip positive for the SD070.[12]

The makers' own adaptor ratings

[edit | edit source]
Adaptor ratings in the makers' leaflets for games Grandstand sold
Grandstand title Maker's version (leaflet) Voltage Current Polarity Plug
Astro Wars Epoch Galaxy II 6 V DC 250-300 mA Centre negative (symbol) Not stated
Invader From Space Epoch Invader From Space 6 V DC 200 mA Not shown Not stated
Firefox F-7 Radio Shack Astro Thunder, cat. no. 60-2197 "6V range" of Radio Shack's 273-1650 adaptor (270-7001 for 240 V UK) Not stated Centre tip negative "the tip that fits the jack"
Munchman Tomy Pac Man (US edition) 7.5 V DC 200 mA Tip (centre) negative 2.1 mm ID coaxial
Tron Tomy Tron 7.5 V DC 200 mA Tip (centre) negative 2.1 mm ID coaxial
Caveman Tomy Caveman (GB edition) 7.5 V DC 200 mA Tip (centre) negative 2.1 mm ID coaxial

Sources: Epoch Galaxy II,[10] Epoch Invader From Space,[19] Radio Shack Astro Thunder,[17] Tomy Pac Man,[11] Tomy Tron[15] and Tomy Caveman[16] leaflets (see Documentation). The Grandstand and maker's versions are the same games according to MAME's driver notes (Astro Wars, Invader From Space, Munchman, Caveman)[14] and the Handheld Museum (Firefox F-7, Tron).[18][20]

The two makers disagree on voltage. All of these games run on four 1.5 V cells, 6 V in total, yet Tomy asks for a 7.5 V adaptor and Epoch for 6 V; none of the leaflets explains the difference.[10][11] Use the figure the maker printed for the game in question. One owner of a Tomy Puckman, the same game as Munchman, ran it from a 6 V DC adaptor wired to the battery terminals.[21] Tomy also tells owners not to use any adaptor other than the type it recommends, and to disconnect the adaptor when the game is not in use.[11][16]

The SD070 needs the opposite polarity

[edit | edit source]
Grandstand Colour Programmable SD070 (6)
Underside of a Colour Programmable SD070. The label asks for "AC adaptor 9V DC 200mA" and shows a jack plug with the sleeve negative and the tip positive (photo José Antonio Ortigueira Amor, CC BY 4.0).

The base label of the Grandstand Colour Programmable SD070 reads "Use 6x1.5V UM-2 batteries or AC adaptor 9V DC 200mA" and shows a jack plug with the sleeve marked negative and the tip marked positive.[12] That is the reverse of the tabletop setting, and a different voltage: 9 V against 6 V or 7.5 V.

No SD070 leaflet was found, so it is not known whether Grandstand recommended the Universal Mains Adaptor for it. If one is used, or any switchable supply that was last set up for a tabletop game, the polarity switch must be moved and the output checked before the plug goes in. No account was found of what a reversed supply does to an SD070, and nothing published shows whether the console has a protection diode on its input. Treat a reversed or wrong-voltage supply as able to damage it, as Grandstand's own leaflets warn for their games.[9]

The other TV games photographed on Wikimedia Commons also take 9 V, but their labels show no polarity. The owner who photographed them gives the polarity in his own write-ups (last column); this is one collector's account, not a printed marking:

Supply printed on Grandstand TV game labels
Console Batteries Adaptor Polarity shown Owner's account
TV Game 2000 Six UM-2 (C), 9 V "AC adapter 9V"; the case is moulded "POWER CONSUMPTION 360mWATT, 9V DC" (about 40 mA) No[22] Centre negative[23]
TV Game 3600 Mk II Six UM-2 (C) 9 V, 100 mA No[24] Centre positive[25]
Model 4600 Six UM-2 (C) 9 V DC, 100 mA No[26] Centre positive[27]
Colour Programmable SD070 Six UM-2 (C) 9 V DC, 200 mA Yes: tip positive[12] Centre positive[28]

For a console with no polarity on its label, find the original adaptor or trace the socket. With the batteries out, a continuity test from the socket's centre contact to the battery-box terminals usually shows which side of the supply the centre belongs to. If the result is unclear, do not guess.

Choosing a modern replacement

[edit | edit source]

A replacement adaptor has to match the voltage, supply at least the current the equipment needs, and have a plug that fits.[29] For these games the polarity must also match. An old unregulated adaptor can give much more than its label voltage when lightly loaded, which can damage the equipment it feeds; a modern switched-mode supply holds its voltage much more steadily as the load changes.[29] A regulated supply of the right voltage is therefore the safer choice for a forty-year-old game, and a supply rated for more current than the figure below does no harm.

Replacement supply by product family, from the leaflets and labels
Product family Titles Voltage Current Polarity Plug
Epoch-made VFD tabletops Astro Wars, Invader From Space, Firefox F-7 6 V DC[10][19][17] 250-300 mA (Galaxy II); 200 mA (Invader From Space)[10][19] Centre negative[10][17] Size not stated; measure the socket
Epoch-made VFD tabletops with no maker's figure found Crazy Monster, Star Force, Scramble, The Big Game Soccer Not published; the cells give 6 V Not published Grandstand leaflets: "negative" (Crazy Monster, Star Force)[6][8] Not stated
Tomy-made VFD tabletops Munchman, Tron, Caveman 7.5 V DC 200 mA Centre negative 2.1 mm ID coaxial[11][15][16]
VTech-made VFD tabletop Cosmic Invader No adaptor rating found; four AA cells[30] Not published Not published Not known
Tomy Multicolorlaser 6000 colour LCD games BMX Flyer, Thomas the Tank Engine Leaflets name only the Grandstand adaptor; a collector gives 6 V DC for BMX Flyer[31] 200 mA or more (collector)[31] Negative (leaflets);[9][4] "Center Pole Negative" (collector)[31] Not stated
Pocket LED and LCD games See Grandstand Handheld and Pocket Games None of the pocket-game leaflets seen mentions an adaptor[32][33] - - -
Colour Programmable SD070 Grandstand Colour Programmable SD070 9 V DC 200 mA Tip positive Jack plug (label drawing)[12]
Earlier TV games TV Game 2000, 3600 Mk II, Model 4600 9 V DC 100 mA (3600 Mk II, 4600); about 40 mA from the 2000's power rating Not shown on the labels Not stated[22][24][26]

Checking an adaptor before use

[edit | edit source]
  1. Set the voltage and polarity for the game from the table above. For a game with no published figure, the batteries give the voltage the circuit runs on: four 1.5 V cells make 6 V.
  2. Plug the adaptor into the mains with nothing connected to it. Put the meter's red lead on the plug's centre pin and the black lead on its outer sleeve. A negative reading means centre negative, as the tabletop games need; a positive reading means centre (tip) positive, as the SD070 needs.
  3. Check the size of the reading. An old unregulated adaptor, or the Universal Mains Adaptor itself, may read well above its rating with no load.[29] Measure again with the game connected if you can.
  4. Connect the game with it switched off, then switch on.
  5. Disconnect the adaptor from the mains when the game is not in use, as the Grandstand and Tomy leaflets say.[9][4][16]

If a tabletop game runs from an adaptor but not from batteries, or the other way round, the fault is often in the power socket's switch contact; see that game's own troubleshooting guide, listed on the Grandstand category page.

Mains safety

[edit | edit source]

The Universal Mains Adaptor is a 240 V mains device now around forty years old. Its label carries the double-insulation symbol,[3] which means it has no earth connection and relies on its case and internal insulation to keep mains voltage away from the user. The hazard is mains voltage reaching a hand through a cracked case, a damaged pin or lead, or a broken internal part.

Before plugging one in:

  • Look for cracks or crazing in the case, and shake it gently: a loose part rattling inside means something has broken free.
  • Check the mains pins or lead for damage and the output lead for splits, especially where it leaves the case and at the four-way plug.
  • Plug it in with nothing connected, check it with a meter as above, and check that it does not get hot with no load.

If you open one, unplug it first. Inside, the transformer's primary winding and its connections are at mains voltage whenever the adaptor is plugged in, and a double-insulated unit depends on the case going back together exactly as it came apart, with no exposed metal and no mains wiring that can touch the low-voltage side. A modern regulated supply of the right voltage and polarity avoids depending on a forty-year-old mains unit.

Documentation

[edit | edit source]

Grandstand leaflets that name the adaptor:

The makers' leaflets for the same games, with their adaptor ratings:

[edit | edit source]

References

[edit | edit source]
  1. ↑ Handheld Museum, "Grandstand Astro Wars" (retrieved 2026-10-18): 1981, VFD, four C cells, model 11183, licensed from Epoch (Galaxy II).
  2. ↑ Handheld Museum, "Grandstand Thomas the Tank Engine" (retrieved 2026-10-18): Thomas the Tank Engine & Friends, 1984, LCD, four AA cells, model 5151-0; one of the Tomy Multicolorlaser 6000 series.
  3. ↑ 3.0 3.1 3.2 3.3 3.4 3.5 3.6 3.7 Handheld Museum, "Grandstand Universal Mains Adapter" (retrieved 2026-10-18). Collector's entry: model UGT; "AC adapter sold by Grandstand in England/U.K. for their handheld/tabletop games. Made for the 240 volt system"; "Has a switch to toggle the polarity and turn the output off completely. Power output is 6-9v DC at 1.5vA (100-200 mA adapters will run these games)." Photographs of the adaptor (label with the double-insulation symbol; four-way plug) and of its box ("Grandstand Leisure Products universal mains adaptor, Suitable for Electronic Games and Toys").
  4. ↑ 4.0 4.1 4.2 4.3 4.4 4.5 4.6 Grandstand, Thomas the Tank Engine instructions (printed in Japan), PDF p. 2: four Duracell MN1500 alkaline batteries; "Adapter socket": Grandstand Universal Mains Adaptor; "Select the appropriate plug on the Universal 4-way jack plug fitted to the adaptor cable"; "Select negative - polarity on the adaptor polarity switch"; "Please read the instructions supplied with the adaptor carefully before use"; disconnect from the mains when not in use. PDF p. 6, "Operational precautions": using the wrong adaptor could damage the game. Hosted as File:Grandstand Thomas the Tank Engine Instructions.pdf.
  5. ↑ 5.0 5.1 Grandstand, Astro Wars instruction leaflet (Adam Leisure Group PLC, Harrogate; game copyright 1981 Epoch, made in Japan), PDF p. 2, "Batteries": four Duracell MN1400 recommended; can be operated from the mains with a Grandstand Universal Mains Adaptor (not included); "Set polarity switch to negative - polarity"; no voltage given; erratic display means weak batteries. Hosted as File:Grandstand Astro Wars Instructions.pdf.
  6. ↑ 6.0 6.1 6.2 Grandstand, Crazy Monster directions (Adam Imports Ltd, Harrogate; made in Japan), PDF p. 1, "Batteries": four Duracell MN 1400; Grandstand Universal Mains Adaptor (not included); set polarity switch to negative polarity; do not leave in the sun or allow it to get wet. Hosted as File:Grandstand Crazy Monster Instructions.pdf.
  7. ↑ 7.0 7.1 Grandstand, Firefox F-7 instruction booklet (Adam Imports Ltd, Ripon Way, Harrogate; made in Japan), PDF p. 1, "Batteries": four Duracell MN1400; Grandstand Universal Mains Adaptor (not included); set polarity switch to negative polarity. Hosted as File:Grandstand Firefox F-7 Instructions.pdf.
  8. ↑ 8.0 8.1 8.2 Grandstand, Star Force instruction booklet (distributed by Adam Imports Ltd, Ripon Way, Harrogate), PDF p. 1, "Batteries": four Duracell MN1400; Grandstand Universal Mains Adaptor (not included); set polarity switch to negative polarity; drawing of the adaptor plug entering the left side of the case. Hosted as File:Grandstand Star Force Instructions.pdf.
  9. ↑ 9.0 9.1 9.2 9.3 9.4 9.5 Grandstand, BMX Flyer instruction book (printed in Japan), PDF p. 1 (four Duracell MN1400 alkaline batteries; can be run from the mains with a Grandstand Universal Mains Adaptor) and p. 4: "Adaptor socket" (the universal jack plug is different to that illustrated; "select negative polarity on the adaptor polarity switch"; always disconnect the adaptor from the mains when not in use) and "Operational precautions" (use a Grandstand Universal Mains Adaptor, "Using the wrong adaptor could damage the game"; replace all the batteries when the display fails or the illumination becomes dim or uneven). Hosted as File:Grandstand BMX Flyer Instructions.pdf.
  10. ↑ 10.0 10.1 10.2 10.3 10.4 10.5 10.6 Epoch, Galaxy II instructions (Epoch Corporation, Englewood, N.J.; copyright 1981 Epoch Company Ltd, Tokyo), PDF p. 2, "Batteries": four C cells or an A/C-D/C adapter; "Power requirement for A/C-D/C adapter 6-Volts DC, 250~300 ma"; polarity symbol with the positive sign on the outer ring and the negative sign on the centre dot (read at 1200 dpi). Hosted as File:Epoch Galaxy II Instructions.pdf.
  11. ↑ 11.0 11.1 11.2 11.3 11.4 11.5 Tomy, Tomytronic Pac Man instructions (US edition, copyright 1981 Tomy Corp., Carson, California), PDF p. 1: four C batteries; recommended adapters Archer 270-1551A and Recoton AD-10UL; "Output: 7.5 V DC 200mA; Plug: 2.1mm ID Coaxial Type; Tip (Center) Polarity: Negative". PDF p. 2: unplug the adapter when not in use; do not use any other adapter than the ones recommended. Hosted as File:Tomy Pac Man Instructions.pdf.
  12. ↑ 12.0 12.1 12.2 12.3 12.4 Wikimedia Commons, File:Grandstand Colour Programmable SD070 (6).jpg (José Antonio Ortigueira Amor, CC BY 4.0; copied from Commons). Base label read from the photograph: "UHF CH-36 / 625-I PAL System / POWER SOURCE: Use 6x1.5V UM-2 batteries or AC adaptor 9V DC 200mA", with a jack plug drawn negative on the sleeve and positive on the tip.
  13. ↑ Victoria and Albert Museum, object O27497, Grandstand electronic game (Invader From Space), object history note transcribing the box (retrieved 2026-10-18).
  14. ↑ 14.0 14.1 MAME source, hh_ucom4.cpp at commit d404316 (retrieved 2026-10-18), driver notes listing known releases: Epoch Invader From Space ("UK: Invader From Space, published by Grandstand"); Epoch Galaxy II ("UK: Astro Wars, published by Grandstand"); Epoch Astro Command ("UK: Scramble, published by Grandstand"); Tomy Pac-Man ("UK: Puckman (Tomy), and also published by Grandstand as Munchman"); Tomy Caveman ("UK: Cave Man - Jr. Caveman vs Dinosaur, published by Grandstand").
  15. ↑ 15.0 15.1 15.2 Tomy, Tron instructions (no. 7601), PDF p. 2, "Insert batteries": four C alkaline batteries; "Output: 7.5 V DC 200mA; Plug: 2.1mm ID Coaxial Type; Tip (Center) Polarity: Negative". Hosted as File:Tomy Tron Instructions.pdf.
  16. ↑ 16.0 16.1 16.2 16.3 16.4 Tomy, Caveman instruction book (GB edition), PDF p. 1: four 1.5 V "baby cells" (C); "AC Adaptor Requirements: Output: 7,5 V DC 200 mA; Plug: 2.1 mm ID Coaxial Type; Tip (Center) Polarity: Negative"; "When not in use, disconnect the adaptor. Do not use any other adaptor than the type recommended." Hosted as File:Tomy Caveman Instructions.pdf.
  17. ↑ 17.0 17.1 17.2 17.3 Radio Shack, Astro Thunder owner's manual, cat. no. 60-2197, PDF p. 1, "You must be armed with": four C batteries or AC adapter; "obtain Radio Shack 273-1650 adapter. Select the 6V range. Use the tip that fits the jack on the unit; set the center tip negative"; "Use 270-7001 for 240V U.K., 270-9536 for 240V Australia"; "Even leak-proof type batteries can leak damaging chemicals". Hosted as File:Radio Shack Astro Thunder Manual.pdf.
  18. ↑ 18.0 18.1 Handheld Museum, "Grandstand Firefox F-7" (retrieved 2026-10-18): 1983, VFD, four C cells, model 11279; the same game as Epoch Astro Thunder 7, Epoch Galaga X6 and Radio Shack Astro Thunder.
  19. ↑ 19.0 19.1 19.2 Epoch, Invader From Space instructions (copyright 1980 Epoch Company Ltd), PDF p. 3, "Batteries": four AA cells or an A/C-D/C adapter; "Power requirement for A/C-D/C adapter 6-Volts DC, 200ma"; no polarity symbol. Hosted as File:Epoch Invader From Space Instructions.pdf.
  20. ↑ Handheld Museum, "Grandstand Tron" (retrieved 2026-10-18): 1981, VFD, four C cells, model 11266; Grandstand was the UK distributor of Tomy's Tron.
  21. ↑ Oona Räisänen, "Tomy Electronic PUCKMAN", absorptions (windytan.com), 3 May 2013 (retrieved 2026-10-18): the game takes four C cells, 6 V, or an AC adapter; the author ran it from a 6 V DC adapter connected to the battery terminals; main processor marked D553C-160.
  22. ↑ 22.0 22.1 Wikimedia Commons, File:Grandstand Adman TV Game 2000 (8).jpg (José Antonio Ortigueira Amor, CC BY 4.0), read from the photograph: label "ADMAN GRANDSTAND TV GAME 2000 / POWER SUPPLY: 9V-DC (6×UM-2 BATTERY) OR AC ADAPTER 9V / MADE IN KOREA"; moulded in the case "POWER CONSUMPTION 360mWATT, 9V DC". No polarity marking.
  23. ↑ José Antonio Ortigueira Amor, "Consola Pong Adman Grandstand TV Game 2000", Retro Ordenadores Orty (blog, in Spanish), November 2023 (retrieved 2026-10-18). Owner's description of the console photographed on Wikimedia Commons: external 9 V DC supply, centre negative.
  24. ↑ 24.0 24.1 Wikimedia Commons, File:Adman Grandstand 3600 MK II Colour (15).jpg (José Antonio Ortigueira Amor, CC BY 4.0), read from the photograph: label "COLOR TV-GAME ... BATTERY: UM-2 × 6 OR AC ADAPTOR (9V / 100 MA) ... MADE IN HONG KONG"; socket marked "EXTERNAL POWER". No polarity marking.
  25. ↑ José Antonio Ortigueira Amor, "Consola Pong Adman Grandstand TV Game 3600 Mk II", Retro Ordenadores Orty (blog, in Spanish), November 2023 (retrieved 2026-10-18). Owner's description of the console photographed on Wikimedia Commons: external 9 V DC supply, centre positive.
  26. ↑ 26.0 26.1 Wikimedia Commons, File:Grandstand 4600 colour - Back.jpg (José Antonio Ortigueira Amor, CC BY 4.0), read from the photograph: label "UHF CHANNEL 36 / POWER SOURCE: Use 6×UM-2 Batteries or by AC Adaptor 9V DC 100mA"; "Made in Hong Kong". No polarity marking.
  27. ↑ José Antonio Ortigueira Amor, "Consola Grandstand 4600 Colour Video", Retro Ordenadores Orty (blog, in Spanish), December 2021 (retrieved 2026-10-18). Owner's description of the console photographed on Wikimedia Commons: 9 V DC supply, centre positive; tested working from a 9 V DC centre-positive supply.
  28. ↑ José Antonio Ortigueira Amor, "Consola Grandstand Colour Programmable SD070", Retro Ordenadores Orty (blog, in Spanish), March 2026 (retrieved 2026-10-18). Owner's description of the console photographed on Wikimedia Commons: external 9 V DC supply, centre positive.
  29. ↑ 29.0 29.1 29.2 Wikipedia, "AC adapter" (retrieved 2026-10-18), section on replacement and universal adapters: a replacement must match the input and output voltages, match or exceed the current capability and have a matching connector; some universal adapters switch voltage and polarity; many low-cost supplies are unregulated and, lightly loaded, may put out much more than the nameplate voltage; switched-mode supplies give a much more constant voltage as the load varies.
  30. ↑ Handheld Museum, "Grandstand Cosmic Invader" (retrieved 2026-10-18): 1981, VFD, four AA cells; licensed from VTech, identical to VTech's Sonic Invader.
  31. ↑ 31.0 31.1 31.2 Handheld Museum, "Grandstand BMX Flyer" (retrieved 2026-10-18). Collector's entry: "A/C Adapter: 6v DC, 200mA (or more), Center Pole Negative"; gives four AA cells, where the Grandstand leaflet asks for four C cells.
  32. ↑ Grandstand, Electronic Game Solitaire instructions (printed in Hong Kong, 88-02000-02), PDF p. 5, "How to replace battery": one 9 V battery on a snap connector, door opened with a coin; no adaptor mentioned. Hosted as File:Grandstand Solitaire Instructions.pdf.
  33. ↑ Grandstand, BMX Burner instructions (distributed by Adam Imports Ltd, Ripon Way, Harrogate; printed in Japan), PDF p. 2 and p. 16: two LR44 button cells; no adaptor mentioned. Hosted as File:Grandstand BMX Burner Instructions.pdf.


Retrieved from "https://wiki.retrotechcollection.com/index.php?title=Grandstand_Universal_Mains_Adaptor&oldid=26683"