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Grandstand Astro Wars General Maintenance

From RetroTechCollection
Grandstand Astro Wars Instructions controls drawing
The Astro Wars controls as drawn in Grandstand's leaflet: joystick, POWER slide switch, SELECT, START and FIRE, with the leaflet's batteries box.

Care, cleaning and opening of the Grandstand Astro Wars, the battery-powered space game with a vacuum fluorescent display (VFD) that Epoch made in Japan and Grandstand sold in the UK from 1981. Epoch sold the same game in the USA as Galaxy II, and repair accounts for either name apply to both.[1][2] No Grandstand or Epoch service manual or schematic has been found. What follows comes from the Grandstand and Epoch leaflets, an owner's parts list and the repair logs, forum threads and videos of owners who have opened these games since 2015. Fault-finding is on Grandstand Astro Wars Troubleshooting Guide, and the four electrolytic capacitors are listed on Grandstand Astro Wars Capacitor Replacement Guide.

The Astro Wars at a glance

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Astro Wars: what is inside
Part Detail
Case Silver hood over a black base, with a separate black control panel at the front[3][4]
Fixings Seven cross-head screws on the underside: six round the edge and a smaller one in the middle[5][6]
Cells Four C cells (Duracell MN1400) in a compartment under the base[1]
Adaptor 6 V DC, 250-300 mA, centre negative (Epoch); the Grandstand Universal Mains Adaptor set to negative (Grandstand)[7][1]
DC socket On the right-hand side; it disconnects the cells when a plug is inserted[8][3]
Main board 19096 on the component side, carrying the display, the NEC μPD553C microcontroller (D553C 153), the TY-33 transformer and the power transistor S02 (D882)[2][9]
Control board 96062: POWER slide switch and the SELECT, START and FIRE pads[2][10][11]
Joystick A rocker switch on a small board of its own, joined by a three-wire flat cable[12][13]
Display NEC FIP10xM20T VFD, cyan and red, behind a plate of coloured filter strips and a Fresnel magnifier[2][11]
Sound Piezo sounder, with no volume control or sound switch[14][13]

Before you start

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  • Take the cells out before opening the case. A dead game can be run from a bench supply set to 6 V with a current limit; one repairer started with the limit low and raised it slowly while feeling the power transistor for heat.[15][16]
  • Many of these games have been opened before. Look for missing or loose screws, a power switch refitted the wrong way round and flat cables that have been strained.[17][18]
  • The board is soldered with leaded solder; one owner found a conformal coating on it.[6]
  • The display is a single glass tube. Do not bend it or lever against it; the diode S06 sits under its lower edge and is the part most often reached past it.[15]

Opening the case

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Astro wars
A Grandstand Astro Wars: the silver hood with the display window sits on the black base, and the black control panel carries the joystick, POWER, SELECT, START and FIRE.

The order below is taken from several owners' videos; they agree on the seven screws and on the hood lifting forward off the base.

  1. Take out the cells. The battery cover slides off; many games have lost theirs (see Batteries and battery contacts).[12][18]
  2. Turn the game over and remove the seven cross-head screws on the underside: six round the edge and a smaller one in the middle at the back. Some screws turn but will not drop out of their posts, and leaving one in can crack the plastic when the case is pulled apart.[5][8][18]
  3. Keep the game upside down while separating it. The SELECT, START and FIRE buttons, the fire button's spring and the power slider are loose in the control panel and fall out if it is turned the right way up.[5][12][11]
  4. Hold the control panel and pull the silver hood up and forward off the base. It can need some wiggling or prying.[3][6][5] Philip Bryden counts four screws for the hood and three smaller ones for the control section.[3]
  5. The Fresnel magnifier and the starry backdrop are inside the hood and come out separately for cleaning; the lens lifts out after the screw at one end is undone.[19][5]
  6. Lift off the control panel to reach the POWER switch, the rubber pads with their carbon contacts, the fire button spring and the felt pad over the joystick.[11][12]
  7. Four screws hold the black plate that carries the coloured filter strips in front of the display.[11][8]
  8. The main board is held by four screws from the front. To take the boards out of the base, unsolder the two battery wires (Bryden notes the negative goes to the top terminal and the positive to the bottom) and free the DC socket; the joystick board and control board stay joined to the main board by their flat cables.[3][17][8]

Reassembly. Fit the control panel with its three screws first and then the hood, which keeps the buttons in place.[4] Another method is to load the switches and the fire button with its spring into the inverted panel and lower the case onto it.[8] Bryden found that reassembling upside down let the piezo sounder fall out of its mount, and taped the buttons in instead.[3] Check that the fire button spring sits centrally, or the button feels wrong.[5] Do the screws up gently: a screw post on one game had snapped from overtightening and another had a stripped thread.[8][5]

Cleaning

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  • Grandstand's care note: move the joystick gently, do not press hard on the FIRE button, do not leave the game in the sun and do not let it get wet.[1]
  • The hood, base and control panel can be washed once the electronics are out. Keep water away from the metal parts (springs, tabs and the battery plate), which rust, and from the printed title sticker.[8]
  • The front window and the Fresnel lens are plastic. One repairer removed the cloudiness from a front window with a light polish and cleaned its back with glass cleaner; the window was clearer afterwards but still showed some crazing.[19] An old Fresnel lens can be brittle: a corner broke off one when it was refitted.[20]
  • Debris such as packing paper or tape can collect behind the front lens; it comes out when the lens is lifted.[5]

Batteries and battery contacts

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Epoch Galaxy II underside with 3D-printed battery cover
Underside of an Epoch Galaxy II, the same hardware as Astro Wars, with a 3D-printed battery cover in the compartment under the base (YoxxxoY Jorge, CC BY).

The game takes four C cells; Grandstand recommends Duracell MN1400 and says the game will not work properly on weak batteries. If it malfunctions or the display becomes erratic, check or replace them first. Switch off after play and remove the cells if the game is not used for a long time.[1]

  • Cells left in for years leak. Games stored in lofts with their batteries in turn up with corroded terminals and electrolyte on the board.[21] Light corrosion on the springs can be cleaned off with a small rotary tool or abrasive; one water-damaged Galaxy II had its rusted contacts buffed with scouring powder.[6][16]
  • A stretched contact spring can be unsoldered, reformed with pliers and refitted. The same battery contact is used in the Grandstand Star Force.[19]
  • The cover is often missing, and the cells tend to spring out while they are being loaded.[19][18] 3D-printable replacements exist; one design is listed by its designer as fitting Astro Wars, Galaxy II, Scramble, Firefox F-7 and Star Force among others, and reproduction covers are sold online.[22][12]

DC socket and adaptor

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The DC socket is on the right-hand side of the case. Epoch specifies 6 V DC at 250-300 mA with the centre pin negative, and Grandstand's leaflet says only to set the Universal Mains Adaptor's polarity switch to negative.[7][1][8] Owners who power these games from a bench supply set it to 6 V with negative polarity at the socket.[23][3] See Grandstand Universal Mains Adaptor.

  • The game has no protection against reversed polarity. One repairer added a series diode for that reason.[24]
  • The wrong adaptor is the commonest cause of damage reported by repairers. One Scramble arrived with a 9 V positive-centre adaptor that read nearly 13 V off load; the same repairer found phone chargers and other ill-fitting supplies behind many blown power transistors.[11] Owners have traced failed parts to a wrong adaptor plugged in years earlier.[25][26][27] Measure any adaptor's voltage and polarity before connecting it.
  • The socket has a switch inside it. The battery positive (the red wire) runs through a spring contact that a plug pushes open, so the adaptor disconnects the cells.[3][6][28] When that contact is dirty or bent, the game works on the adaptor but not on batteries. Contact cleaner cured one; on another the spring leaf had to be reformed inside the riveted socket.[3][29] With no plug in, there should be continuity from the battery wire through the socket to the board.[18]

Controls

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Power switch

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The POWER slide switch bridges two contacts on the control board.[6] When it is unreliable, clean the contacts with alcohol or contact cleaner, bend the contact leaves up slightly for more pressure, and put a little grease on the slider.[18][19][28] On one game the switch only worked once the control section was screwed down properly.[3] The switch is handed and can be refitted the wrong way round.[17]

SELECT, START and FIRE

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The three buttons press rubber pads with carbon contacts onto the control board. Clean the pads and the board contacts with isopropyl alcohol; white corrosion on the contacts is common.[8][18][11] A FIRE button that works when its contacts are bridged needs a clean pad and clean contacts; switch cleaner on the pad cured one.[5]

  • The FIRE button has a coil spring. A spring that has slipped out of place or lost its bounce makes the button feel dead; it can be stretched slightly or reseated.[18][19][5]
  • On a Galaxy II the fire spring had worn through the control board and shorted the button line to ground, making FIRE intermittent. An insulating grommet and tape over the worn spot cured it.[14]

Joystick

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The joystick is a rocker switch on its own board, under a felt dust pad, with a three-wire flat cable to the main board.[12][11] Its weak point is that cable where it joins the joystick board: bpharoah found its three pins almost unsoldered, and retro_restos found a conductor snapped by an earlier repairer and trimmed and resoldered it.[13][18] On two games a sluggish or erratic joystick was cured by cleaning its contacts.[18][28] If the stick itself breaks off, replacement rockers are hard to find and a joystick board from a donor game is the practical fix.[12]

The flat cables tire with handling. On one game both the joystick cable and the control board cable broke off during a long repair; keep the boards supported and avoid flexing the cables.[15]

Display, filters and magnifier

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The display is a glass VFD whose phosphors glow cyan and red. The other colours come from strips of tinted film taped to the black plate in front of it, and the Fresnel lens in the hood magnifies the whole display.[2][21][11][14]

  • On games that have been run hot, the filter strips burn and distort and their tape lets go.[11] Reattach loose strips in their original positions before the plate goes back.
  • The getter, the dark mirror patch inside the tube, should still be black; one repairer judged a tube by this and said a cracked tube goes whitish.[6] A broken tube cannot be repaired, and a replacement must come from a scrapped game of the same display revision.[11][2]
  • Do not leave the game in the sun.[1]

Speaker

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The piezo sounder sits in a foam pad in the base. It is loud, and there is no volume control or sound switch.[14][13][18] If it buzzes, wedge it back into its pad.[18] Its two thin wires break easily when the case is opened; one owner found a wire broken off and resoldered it.[3]

What wears, and what to check

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Astro Wars wear points
Part What happens Check
Power transistor S02 (D882) Fails short or open, most often after a wrong adaptor or a failed S06 Grandstand Astro Wars Troubleshooting Guide[11][4]
Battery springs and cover Corrosion, stretched springs, lost cover Clean, reform, print or buy a cover[19][22]
DC socket switch Dirty or bent contact: adaptor works, cells do not Continuity with no plug in[3][18]
POWER switch Dirty or slack contacts Clean, bend leaves, grease[19][28]
FIRE button Dirty pad, displaced spring, spring wearing into the board Clean, reseat, insulate[5][14]
Joystick cable Broken or dry joints at the joystick board Resolder[13][18]
Filter strips Tape lets go; heat distorts the film Reattach[11]
Piezo wires Break when the case is opened Resolder[3]

Storage

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  • Take the cells out.[1]
  • Keep the game dry. A water-damaged Galaxy II had rust on its battery contacts and on the display's pins.[16]
  • Keep it out of the sun.[1]

Preventive maintenance checklist

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  1. Remove the cells and look at the springs for corrosion.
  2. Check any adaptor before use: 6 V DC, centre negative.
  3. With no plug in, check that the cells reach the board through the DC socket.
  4. Clean the POWER switch contacts and the SELECT, START and FIRE pads.
  5. Check the joystick cable joints at the joystick board.
  6. Look at the filter strips and the piezo wires while the case is open.
  7. Do the screws up gently on reassembly.
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References

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  1. ↑ 1.0 1.1 1.2 1.3 1.4 1.5 1.6 1.7 1.8 Grandstand, Astro Wars instruction leaflet (Adam Leisure Group PLC, Harrogate; © 1981 Epoch, made in Japan), hosted here as File:Grandstand Astro Wars Instructions.pdf (PDF page numbers). p. 2: drawing of the controls (joystick, POWER slide switch OFF/ON, SELECT, START, FIRE) and the batteries box: four Duracell MN1400 cells; the Grandstand Universal Mains Adaptor, not included, with its polarity switch set to negative; the game will not work properly on weak batteries; if it malfunctions or the display is erratic, check or replace the batteries; switch off after play and remove the batteries when the game is not used for long periods. Skill level 1 is set and shown at the top of the display at switch-on. p. 3: at switch-on there is an electronic sound and the enemy squadron moves on the display, but play waits for START; a "5" shows the five earth ships; a victory tune at 10,000 points; care note: "move the Joy Stick gently. Do not press hard on the Fire Button ... Do not leave in the sun or allow it to get wet."
  2. ↑ 2.0 2.1 2.2 2.3 2.4 2.5 MAME source, hh_ucom4.cpp at commit d404316 (retrieved 2026-10-18). Driver notes for Epoch Galaxy II: PCB labels 19096 and 96062; NEC μPD553C microcontroller labelled D553C 153; cyan and red VFD NEC FIP10xM20T, revisions B (no. 1-8) and D (no. 2-21) with different graphics; released in the UK by Grandstand as Astro Wars. The file header notes that VFD colours fade after decades.
  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 Philip Bryden, "Trying to fix a Grandstand Astro Wars (Super Galaxian, Galaxy 2) 1981", YouTube, 19 March 2024 (transcript read 2026-10-18). First game: the DC socket switches the positive battery lead and its dirty contact stopped battery operation; contact cleaner cured it (3:09-5:56); a piezo wire had broken off (6:49); the power switch only worked once the control section was screwed down properly (12:40-15:16). Second game, completely dead and drawing no current: a leaking 330 μF 10 V capacitor next to the transformer measured 126 μF and was replaced with 330 μF 25 V, without curing it (27:04-31:02); three C945 small transistors tested good (36:03-37:49); the NEC D882 had failed and a new one cured it (38:13-41:24). Four screws hold the silver hood and three smaller screws the control section; hold the control panel and pull the hood forward; the board is held by four screws from the front; the battery wires are unsoldered, negative at the top and positive at the bottom (22:00-26:31). Reassembled upside down the piezo falls out, so he taped the buttons in instead (9:04-10:09).
  4. ↑ 4.0 4.1 4.2 Kip Hakes, "It burned me last time! The Astro Wars is BACK! Part 2", YouTube, 13 October 2023 (transcript read 2026-10-18). S06 had failed; replaced with three 47 V zeners in series, bands all the same way (1:27-7:41). The replacement D882 fitted in part 1 had been destroyed by the failed S06; a second new D882 and the zener chain cured it (9:10-10:48). Advice: check and replace S06 before fitting a new transistor (16:38). Fit the black control section with its three screws before the silver hood, which keeps the buttons in (14:00-14:17). The display flicker seen on camera is not visible in person (15:44).
  5. ↑ 5.00 5.01 5.02 5.03 5.04 5.05 5.06 5.07 5.08 5.09 5.10 icannotgetafreename, "1981 Astro Wars by Grandstand - button repair", YouTube, 24 February 2024 (transcript read 2026-10-18). Seven screws on the underside, six round the edge and one in the middle; leaving one in can break the plastic; one post had a stripped thread (1:37-2:49). The upper cover wiggles up and out; turn the game upside down so the buttons stay in, and reassemble it upside down (3:39-9:59). The fire button worked when its contacts were bridged, and switch cleaner on the pad and contacts cured it; the fire spring must sit centrally (5:28-10:53). The front lens lifts out after undoing the screw at one end (11:26-11:40).
  6. ↑ 6.0 6.1 6.2 6.3 6.4 6.5 6.6 My Mate VINCE, "Dead 1981 Grandstand Astro Wars Game - Repair Video", YouTube, 31 December 2023 (transcript read 2026-10-18). Seven cross-head screws on the underside; the top separates from the bottom with some prying (1:42). Slight corrosion and brown battery leakage under a spring, cleaned with a rotary tool (0:45, 17:01). The red battery wire runs through the DC socket's switch, which cuts the batteries when a plug is in and can stop them reconnecting when dirty (2:51-3:46). He judged the display good because its getter was still black, adding that a cracked tube goes whitish (2:16). The D882 had a 3 Ω short; it and the C945 next to it were replaced and the game worked (7:39-17:47). The board has a conformal coating (16:26).
  7. ↑ 7.0 7.1 Epoch, Galaxy II instruction leaflet (Epoch Corporation, Englewood, New Jersey; © 1981 Epoch Co. Ltd, Tokyo; made in Japan), hosted here as File:Epoch Galaxy II Instructions.pdf. p. 2: four C cells with the + and − ends aligned, or an AC-DC adapter of 6 V DC, 250-300 mA, with a polarity symbol showing the centre pin negative; the same controls as the Grandstand game.
  8. ↑ 8.0 8.1 8.2 8.3 8.4 8.5 8.6 8.7 8.8 Restoration Central, "Grandstand ASTRO WARS Restoration ~ Clean up 1980", YouTube, 16 March 2023 (transcript read 2026-10-18). The base label calls for four HP11 (C) cells and a negative-polarity adaptor (3:00). Six screws round the underside and one in the middle at the back all have to come out; the hood then has to be eased off (3:00-4:30). The magnifier and the curved black front piece come out on their own screws; four more screws hold the plate with the plastic colour sheet over the display (4:30-7:30). A screw post had snapped from overtightening (7:30-9:00). Two battery wires are unsoldered and the metal tabs bent up to free the plate; the DC socket is on the right-hand side (9:00-12:00). The rubber pads and contacts were cleaned with isopropyl alcohol, showing white corrosion (6:00-7:30). On reassembly the switches and the fire button with its spring go into the inverted front piece and the case is lowered onto it (12:00-13:30).
  9. ↑ bobmoo79, Astro Wars parts list (image posted in the Handheld Museum forum thread "Astro wars / galaxy ii repair", 7 December 2018, edited to January 2019; retrieved 2026-10-18). Compiled by the owner from his board: S02 D882 NPN; S03, S04, S05 C2785 NPN; S06, S07, S08 diodes, type not identified; S09 zener 11.5 V; S10 zener 7.5B2 (7.5 V); transformer TY-33; electrolytics C01 220 μF, C02 330 μF, C03 47 μF, C04 10 μF (no voltages given); ceramic C05, C06 47 nF (473Z), C07 2.2 nF (222K), C08, C09 1.2 nF (122K), C10, C11 0.47 nF (471K); resistor packs R01 95k, R02-R04 92k, R05 22k (five 22k resistors, no common pin); R06 333 Ω, R07 620 Ω, R08 2.2k, R09 3.9k, R10 8.2k, R11 1M; X01 400 kHz; display FIP10DM20T; microcontroller D553C-153.
  10. ↑ Handheld Museum, "Guts" (retrieved 2026-10-18): photograph of an opened Grandstand Astro Wars showing main board 19096 standing in the case with the display, control board 96062 marked START, SELECT and FIRE, and the joystick on a small board of its own.
  11. ↑ 11.00 11.01 11.02 11.03 11.04 11.05 11.06 11.07 11.08 11.09 11.10 11.11 11.12 retro_restos, "Astro Wars 'No Display' Repair ... VFD Game Transformer Replaced", YouTube, 14 November 2023 (transcript read 2026-10-18). Repairer who reports fixing 5-10 Astro Wars a week. Phone chargers and the wrong adaptors blow the power transistor; a Scramble that came with a 9 V positive-pin adaptor reading nearly 13 V; "all of these games were a negative polarity and only run at 6 volts" (1:00-3:00). His repair kit contains a power transistor, all the electrolytic capacitors, a DC input socket and a diode, and its notes say to replace S02, the input socket and S06, in that order, as the commonest faults; a broken display tube, rotten battery terminals or a broken joystick need donor parts (3:00-6:00). Seven screws, some holding the silver hood and three holding the control panel, the smallest in the middle; hold the base of the controls and lift up and forward (8:00-10:00). Inside: Fresnel screen and backdrop; fire button and its spring, power and start switches whose contact leaves can be bent for more spring; felt cover over the joystick; carbon contacts on the SELECT, START and FIRE pads (10:00-12:00). Four screws hold the cover with the colour lens; on overheated games this lens burns, distorts and its tape comes off (12:00). This game had sound and no display because its transformer coil had fallen apart, a failure he had not seen in 50-100 repairs; a transformer from a donor board, fitted by its orientation arrow, cured it (12:00-24:00). He greases the power switch slider (26:00).
  12. ↑ 12.0 12.1 12.2 12.3 12.4 12.5 12.6 Chris's Retro Corner, "Grandstand Astrowars (Epoch Super Galaxian / Galaxy II) - Joystick fix", YouTube, 15 August 2020 (transcript read 2026-10-18). A joystick broken off at the stick; such rocker switches are "surprisingly hard to find nowadays" (0:36-0:53); the joystick board from a donor game was swapped in by unsoldering its three wires (1:45-8:48). Work with the game upside down so that the buttons do not fall out; a felt pad sits on the joystick (5:30-5:48). A reproduction battery cover bought online fitted well (13:28-14:23).
  13. ↑ 13.0 13.1 13.2 13.3 13.4 bpharoah, "Astro Wars!", 29 April 2020 (retrieved 2026-10-18). Joystick dead: the cable from the joystick board was intact, but on the other side of the joystick board its three pins had almost no solder; resoldering them cured it. Power is four C cells or a 6 V DC adaptor; the piezo speaker is very loud.
  14. ↑ 14.0 14.1 14.2 14.3 14.4 Retro Tech Teardown, "Epoch Galaxy II [1981 - Retro Tech Teardown 002"], YouTube, 23 December 2015 (transcript read 2026-10-18). An Epoch Galaxy II: no way to turn the sound off; a large Fresnel lens; colour gels over the single glass display tube; the fire button's contact spring had worn into the control board and shorted the button line to ground, making the button intermittent; a plastic grommet and insulating tape over the worn spot cured it (1:30-3:00, 7:30-14:00).
  15. ↑ 15.0 15.1 15.2 Retro Tech Repair, "Astro Wars Repair (sound but no display or faint display)", YouTube, 29 January 2021 (transcript read 2026-10-18). Faint sound and no display on several games. Measured on a working board: about −1.5 V at the D882 base, −3 V at the base of S03 (a C945), fed from a −9 V line through the zener S09, and the −10 V microcontroller supply (24:00-33:00). A 10 μF capacitor next to the transistor and transformer, rated 16 V, was replaced with a 25 V part, and later the whole board was recapped, without effect (21:00-31:00). Earlier boards, with the Epoch logo, have one diode S06 under the display; later boards have two, S06 and S11, in series (39:00-46:00). The removed diodes broke down at about 140-143 V when tested on a stack of 9 V batteries, which he warns is not safe (48:00-54:00). On a Japanese Astro Wars ruined by the wrong charger, the D882 was burnt; a new D882 still overheated until S06 was replaced with a 1N5275B; the game then drew about 0.2 A with the D882 a little warm, and ran for several hours (57:00-67:00). S06 sits under the bottom edge of the display; bending the tube risks cracking it (61:00). The flat cables to the joystick board and power board broke after repeated handling (39:00).
  16. ↑ 16.0 16.1 16.2 PghGameFix, "Try To Fix Ep2: Epoch Galaxy II (Grandstand Astro Wars)", YouTube, 12 October 2021 (transcript read 2026-10-18). A water-damaged Galaxy II with rusted contacts: four screws inside the case; wires to be desoldered before the boards come out (8:16-9:33). A crusty electrolytic marked 47 μF 50 V measured 0.11 Ω ESR in circuit, within specification; no other capacitor showed leakage (13:03-15:36). The battery feed is cut by a switch inside the DC socket (33:26). Sound but no display: a cracked glass diode at S10 (marked B1 and apparently 7.5) was replaced with a zener of unknown value from another device and the display returned (34:20-42:20).
  17. ↑ 17.0 17.1 17.2 Retro Tech Repair, "Grandstand Astro Wars / Galaxy II repair", YouTube, 16 December 2018 (transcript read 2026-10-18). A dead Astro Wars that someone had already opened: loose screws and a stiff power switch refitted the wrong way round (1:00-3:10); one fixing still holding the case until he found it under the front panel (1:55-2:18); a Fresnel lens and a removable screen (2:34); two battery wires unsoldered to free the boards from the plastics (4:45); joystick board and power board each joined by a flat cable, no bulging capacitors, a step-up transformer (5:34-6:00); the power transistor, whose base, collector and emitter are marked on the board, had a base-emitter short; a new one cured it (10:00-13:30).
  18. ↑ 18.00 18.01 18.02 18.03 18.04 18.05 18.06 18.07 18.08 18.09 18.10 18.11 18.12 18.13 retro_restos, "Astro Wars Repair No Power & Broken Joystick", YouTube, 12 June 2023 (transcript read 2026-10-18). Adaptor: 6 V, negative tip (2:00). About seven screws, the middle one smaller; screws that do not drop out; the base tray is pulled forward to free the case (2:00-4:00). The fire button spring had come out of place; the power switch leaves were cleaned with alcohol and bent slightly (4:00). The batteries run through the DC socket, which disconnects them when a plug is inserted; continuity across the two red wires with no plug in (6:00). Four screws free the display (7:30). The D882 read as a resistor; a new one restored sound and display; the electrolytics tested good on an ESR meter and were left alone (10:00-13:00). Carbon pads cleaned with alcohol, switch cleaner on the joystick (14:00). The three-wire joystick cable had been snapped at the joystick board by an earlier repairer; trimmed and resoldered (18:00-22:00). The display appears to flicker on camera because of the shutter speed, not in real life (18:00, 24:00).
  19. ↑ 19.0 19.1 19.2 19.3 19.4 19.5 19.6 19.7 retro_restos, "Grandstand Astro Wars Service & Repair from Ebay Vintage Games Bundle", YouTube, 2 October 2024 (transcript read 2026-10-18). Strip-down service: carbon contacts cleaned; power slider contacts bent for spring and greased; fire button spring stretched slightly (2:00-4:00). A stretched battery spring was unsoldered, reformed with pliers and refitted; the Star Force has "exactly the same battery contact" (4:00-8:00). The Fresnel screen, star backdrop and front screen come out; the front screen was polished and its back cleaned with glass cleaner (10:00-12:00). "Astro Wars is notorious for throwing the batteries out when you're trying to put them in" (16:00).
  20. ↑ Buy it Fix it, "I Bought 2x 'UNTESTED' Grandstand Astro Wars.. Can I fix them?", YouTube, 20 August 2022 (transcript read 2026-10-18). Faint sound and no display: a new D882 still got hot; the diode under the display, S06, measured short; three 47 V zeners in series (141 V), all facing the same way, cured it (1:00-29:39). Second game: power switch contacts cleaned after an earlier opening; the star backdrop was missing and a corner of the brittle Fresnel lens broke off when refitted (16:21-23:55).
  21. ↑ 21.0 21.1 Retro Games Now, "Astro Wars by Grandstand" (retrieved 2026-10-18). Collector's buying guide: games stored in lofts with the batteries in have corroded terminals and electrolyte on the board; a display that fades "cannot be replaced"; the display itself shows two colours, with the others made by coloured film.
  22. ↑ 22.0 22.1 YoxxxoY Jorge, "Battery cover Epoch electronic games", Thingiverse 3399673 (2 February 2019), archived on the Internet Archive (retrieved 2026-10-18). 3D-printable battery cover; the designer lists Astro Thunder, Astro Thunder 7, Firefox F-7, Astro Command, Astro Wars, Space Defender, Galaxy II, Star Force and Scramble. Licensed CC BY.
  23. ↑ bpharoah, "More Astro Wars!", 24 April 2023 (retrieved 2026-10-18), with photographs. A dead game: 6 V with negative polarity at the DC socket; traced on the red wire to the power switch, bridged with a crocodile clip, and through the control panel cable to the main board; no leaking or bulging capacitors; the D882 power transistor had a base-emitter short; a new transistor cured it.
  24. ↑ Andy van Stokkum, "Repairing an Astro Wars", codify.nz, 15 June 2019 (retrieved 2026-10-18), with photographs of the opened game. S02 ran hot and was replaced; the game worked for about a month, then S02 failed again and S03 ran hot; finally replaced S06 (140 V zener; 2 W parts fitted where a 500 mW 1N5275B would do), S03-S05 (2SA1175), S02 (D882) and "all electrolytic capacitors (as labelled)". The adaptor plug is outer-positive and the game has no reverse-polarity diode; he added one. It runs from 5 V but the display is less bright than at 6 V.
  25. ↑ All About Circuits forum, "Grandstand Astro Wars Game (Faulty) - help with component identification", February 2019 - January 2024 (retrieved 2026-10-18). bobmoo79: the circuit takes 6 V and makes −10 V for the microcontroller and −39 V for the display (measured on a working game); with the failed S06 the D882 (S02) gets very hot, the supply drops to about 2.5 V and the game draws 1.5 A; S06 is an orange glass diode with a red and a brown band (another member's has a single red band). Later posts: one member fixed the same fault with a 1N5275B zener; another fixed a game he had damaged in about 1985 with "the wrong mains brick" by replacing S06.
  26. ↑ All About Circuits forum, "Help with replacement part - Repairing old electronic game", August-October 2022 (retrieved 2026-10-18). Of two Astro Wars, one was cured by a new D882; the other, damaged when the wrong adaptor was plugged in, had the S06 fault. The 1N5275B is a 140 V, ½ W zener (an NTE5054A is given as an equivalent); the game was repaired with two 1N4760 68 V zeners in series in place of S06.
  27. ↑ Handheld Museum forum, "Astro wars / galaxy ii repair", pages 1-2, December 2018 - February 2019 (retrieved 2026-10-18). Owner bobmoo79's dead white-lettered Astro Wars: the D882 ran very hot, the supply fell to about 1.5 V and the game drew 1.5-1.7 A; a replacement D882, then all new transistors and all new electrolytic capacitors, made no difference; S06 read about 20 Ω both ways; with S06 lifted the μPD553 received its −10 V and ran when the display was fed separately; an S06 taken from a working red-lettered game ("a slightly different PCB revision") cured it. S06 is a glass diode with no printing, its cathode on transformer pin 1; with the good part fitted about 10 mA flows through it at 39 V; 32 V and 39 V zeners overheated. Transformer connections traced: pins 1, 2 and 5 ground, pin 3 +6 V, pin 4 S02 collector, pins 6 and 10 the display filament (display pins 1 and 30). Also a μPD553-to-display pin map credited to kevtris and an out-of-circuit display test (about 3 V on the filament, 12 V on a grid and a segment) whose voltages the owner did not guarantee. Other members: a healthy game should draw "more like 100mA" (blanka); the wrong AC adapter "will usually fry" a transistor, "the most frequent damage I've seen to VFD games" (Rik, site administrator).
  28. ↑ 28.0 28.1 28.2 28.3 Retro Tech Repair Shop, "80's Grandstand Astro Wars game. Sold as untested on eBay", YouTube, 14 November 2020 (transcript read 2026-10-18). Dead on batteries but working when the bench supply was connected past the battery box: the battery positive runs through a contact inside the DC socket that opens when a plug is inserted, so that the batteries cannot be back-charged; the power switch contacts were worn and were bent up for more tension; the joystick contacts were cleaned (2:42-9:27).
  29. ↑ My Mate VINCE, "1981 Grandstand ASTRO WARS Tabletop Game - No Power Fault - Trying to Fix", YouTube, 10 January 2021 (transcript read 2026-10-18). A previous owner had found a 330 μF 10 V capacitor blown on the +6 V line and replaced it, all the capacitors and the power transistor, but the new transistor kept overheating (0:00-3:00). The DC socket's battery contact did not reconnect the cells: a spring leaf rests on a shelf inside the riveted socket and the plug pushes it away; it was reformed and soldered as a temporary repair (6:00-21:00). Flat-cable joints and lifted pads were repaired with wire (12:00). The small transistor that drives the power transistor's base (marked C945) had a base-collector short; with it replaced the game ran, but the display was too dim to see and the power transistor ran very hot; a different power transistor (a BD139 as a stopgap) made the display bright. He concluded that the original faults were the blown capacitor, the small transistor and the power transistor (24:00-39:00). With a heatsink added to the power transistor, the board "just about fits but it is quite tight" in the case (33:00).


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