Grandstand Astro Wars Troubleshooting Guide
Symptom-by-symptom fault-finding for the Grandstand Astro Wars and Epoch's identical Galaxy II.[1] No manufacturer's schematic or service data has been found. The figures and fixes below come from owners who traced the power circuit on working and faulty games between 2015 and 2025, in forum threads, repair logs and videos; where they disagree, the page says so. Opening the case and routine care are on Grandstand Astro Wars General Maintenance; capacitor values are on Grandstand Astro Wars Capacitor Replacement Guide.
How the power circuit works
[edit | edit source]The four C cells give 6 V, but the NEC μPD553 microcontroller is a PMOS part that runs from about −10 V, and it drives the display directly at voltages down to about −35 V.[2] The game therefore makes its own negative supplies. The power transistor S02, a D882, switches 6 V through the small TY-33 transformer, which feeds the display filament; the −10 V and −39 V supplies are derived from it.[3][4][5] The small transistor S03 drives S02's base.[6][7] The diode S06 is connected to a transformer winding that one owner measured at about 200 V peak to peak, and it breaks down at about 140 V.[3][6] When S06 fails short it loads the converter so heavily that S02 overheats and the supply collapses. That is why a dead Astro Wars so often has a hot power transistor, and why a new transistor fitted without checking S06 can fail in the same way.[3][8][5]
The microcontroller plays the game and sound even when the display supply is missing: owners with a failed S06 or a failed transformer heard the game running with a dark display.[6][9][10]
What should happen at power-on
[edit | edit source]With four good C cells, or a 6 V centre-negative supply, and POWER switched on:[11]
- An electronic sound plays and the enemy squadron moves on the display, but play does not start until START is pressed.
- Skill level "1" shows at the top of the display. SELECT steps through levels 1 to 4 before a game.
- START begins play and a "5" shows the five earth ships.
- The joystick moves the ship left and right, and FIRE launches a missile; another can only be fired once the last has hit an alien or left the display.
Expected measurements
[edit | edit source]| Point | Working game | With S06 failed short | Source |
|---|---|---|---|
| Supply at the board (+6 and GND pads) | 6 V | Falls to about 1.5-2.5 V | [3][5][12] |
| Supply current | About 0.2 A measured on one repaired game; one member expected about 100 mA | 1.5-1.7 A (2.2 A on one game where S06 was not checked) | [6][3][12] |
| Microcontroller supply | About −10 V | About −5 V on one game | [5][3] |
| S02 (D882) base | About −1.5 V | [6] | |
| S03 base | About −3 V, from a −9 V line through zener S09 | [6] | |
| Display supply | About −39 V | Absent | [5][3] |
| Current through S06 | About 10 mA | [3] | |
| S06 breakdown, out of circuit | About 140-143 V | Reads about 20 Ω both ways | [6][3] |
These are a handful of owners' readings on one or two games each, taken with ordinary meters, a home-built oscilloscope and a stack of 9 V batteries; treat them as a guide.[3][6] The transformer's pins, as one owner traced them: 1, 2 and 5 ground; 3, +6 V; 4, the collector of S02; 6 and 10, the display filament (display pins 1 and 30); 7 and 9 unconnected; 8 not identified.[3]
Use a current-limited bench supply at 6 V for a game of unknown state, connected to the +6 and GND pads or the DC socket, and watch the current and the temperature of S02. Several repairers bridged the POWER switch to keep both hands free.[6][13][12]
Symptoms
[edit | edit source]| Symptom | Likely cause | Action | Source |
|---|---|---|---|
| Dead on cells and adaptor; S02 gets hot within seconds; supply sags | S06 failed short; S02 may also have failed | Switch off quickly. Lift one leg of S06 and measure it; replace S06, then S02 if it reads short or has been cooking. See S06. | [3][5][8] |
| Dead on cells and adaptor; nothing hot | S02 failed short base-emitter, or failed open; or a break in the supply path | Test S02 out of circuit; a good D882 reads as a diode from base to collector and base to emitter, and not the other way. If S02 is good, follow 6 V from the socket through the POWER switch and the flat cable to the main board. | [14][15][16][17] |
| A new D882 overheats or fails again | S06 still faulty; or the driver transistor S03 has failed | Check S06 before fitting another transistor. Test S03 out of circuit. | [8][7][12] |
| Sound plays but the display is dark or faint | S06 failed; on a water-damaged game, the zener S10; very rarely the transformer | Measure the −39 V display supply. Check S06 and S10. Inspect the transformer windings. | [10][18][9] |
| Display dim but readable | Low supply: weak cells, running at 5 V, or a failing power transistor | Check the cells. On one game the display stayed too dim to see, with S02 very hot, until S02 was replaced again. | [11][19][7] |
| Works on the adaptor, dead on cells | DC socket contact not reconnecting the cells; corroded springs; broken battery wire | Check continuity through the socket with no plug in; clean or reform the contact. | [16][20][7] |
| Works on cells, dead or damaged on the adaptor | Wrong polarity or voltage | Measure the adaptor: 6 V DC, centre negative. | [21][9] |
| Game misbehaves; display erratic | Weak cells | Fit fresh cells. | [11] |
| Starts, then stops; POWER switch unreliable | Dirty or slack switch contacts; control section not screwed down | Clean and tension the contacts; screw the panel down. | [16][20] |
| Joystick dead in one or both directions | Broken or dry joints where the flat cable meets the joystick board; dirty rocker contacts | Resolder the three joints; clean the rocker. | [22][15][20] |
| FIRE dead or intermittent | Dirty pad or contacts; displaced spring; spring worn through the board | Bridge the contacts to test; clean; reseat the spring; insulate a worn spot. | [23][24][15] |
| No sound, display normal | Piezo wire broken off | Resolder the wire. | [16] |
| Smoke or a burning smell at switch-on | S02 failing, usually after a wrong adaptor or with S06 short | Switch off; do not keep powering it. | [13][25][6] |
Known faults
[edit | edit source]S02, the power transistor
[edit | edit source]The D882 at S02 is the part most often replaced. In the reports it has failed short base to emitter, failed nearly short between all its legs, burnt a hole in its case, or simply stopped conducting; a new D882 alone cured games for Retro Tech Repair, bpharoah, retro_restos and Philip Bryden, and a new power transistor (type not named) cured one for Repairing Faulty Tech.[26][14][15][16][17] Wikipedia and a collector's guide say, without a source, that the D882 "is known to fail frequently"; the repair reports bear that out.[27]
- The board marks S02's base, collector and emitter; one repairer's replacement ran hot because it went in the wrong way round.[26][17]
- A D882 can test good on a meter when cold and still be the part that is running hot. Retro Tech Repair found that his hot transistor was being destroyed by a failed S06, not failing on its own.[6]
- Rik of the Handheld Museum forum writes that a wrong AC adapter "will usually fry" a transistor in these games, and that replacing all the transistors without testing them "works quite a lot".[3]
S06, the high-voltage diode
[edit | edit source]S06 is a small glass diode with no printed value, tucked under the lower edge of the display. Owners describe it with a red and a brown band, a red and a gold band, or a single red band; its direction is marked on the board.[5][3][25] When it fails it reads about 20 Ω in both directions, S02 overheats and the game is dead, or plays sound with no display.[3][10][8]
Board versions. Of the two boards Retro Tech Repair compared, the earlier one, which carries the Epoch logo, had the single diode S06, and the later one had two diodes, S06 and S11, in series in the same place. He suggests the second diode was added for reliability.[6] bobmoo79 found that his working red-lettered game had "a slightly different PCB revision" in this part of the circuit from his faulty white-lettered one.[3] Look for S11 beside S06 before ordering parts.
Replacements that have worked:
- a 1N5275B (140 V, ½ W zener), on at least three games;[6][5][28]
- two 1N4760 (68 V) zeners in series;[29]
- three 47 V zeners in series, about 141 V, all with their bands the same way;[10][8]
- a 140 V, 2 W zener, physically larger;[19]
- the pair of diodes from a scrapped Grandstand Scramble board, which has S06 and S11 in series in the same circuit.[6]
Parts that did not work were 32 V and 39 V zeners, which overheated or left S02 overheating, and a BAT85 Schottky diode, which burnt out.[3][28]
Fit the new part the same way round as the old one, keep its leads clear of the display pins, and replace S02 at the same time if it has been running hot.[8][10][19] Kip Hakes destroyed a new D882 by powering up before replacing S06, and advises changing S06 first.[8]
Wikipedia mentions S06 failing, without a source.[27] Testing a removed S06 needs well over 140 V; Retro Tech Repair did it with a stack of 9 V batteries and a 10 kΩ resistor, and warns that it is not safe. A reading of a normal diode drop one way and open the other on a meter does not prove S06 good.[6]
S03, the driver transistor
[edit | edit source]S03 is a small NPN transistor that drives S02. On the boards opened by Retro Tech Repair and My Mate VINCE it was marked C945; Philip Bryden found three C945s on his board. bobmoo79's parts list gives C2785 for S03, S04 and S05, and Kip Hakes's tester read his S03 as a C1841. One repairer replaced S03-S05 with 2SA1175s, which are PNP types. The sources conflict, so read the markings on your own board before buying.[6][7][16][4][13][19] On one game the previous owner's new D882s kept overheating because the transistor driving S02 (marked C945) had a base-collector short; with it replaced and a fresh power transistor fitted, the display came back bright.[7]
Capacitors
[edit | edit source]The electrolytics have rarely been the fault. Bryden's dead game had a leaking 330 μF 10 V capacitor that had fallen to 126 μF, but replacing it did not cure the game; the D882 did. The owner of another game found the same value blown on the +6 V line, together with a failed D882 and S03. bobmoo79, codify and Retro Tech Repair each replaced every electrolytic without effect on their faults, and retro_restos and PghGameFix found the capacitors good on an ESR meter.[16][7][3][19][6][15][18] Values are on Grandstand Astro Wars Capacitor Replacement Guide.
Transformer
[edit | edit source]retro_restos opened a boxed, barely used game with sound and no display and found the transformer's windings had come apart. He replaced it from a donor board, matching the orientation arrow on its top, and calls the failure the only one he had seen in 50-100 Astro Wars repairs.[9] Retro Tech Repair swapped transformers between games while hunting another fault and found no difference.[6]
S10
[edit | edit source]On a water-damaged Galaxy II with rusted parts, the glass diode at S10, marked B1 and apparently 7.5, had cracked. A zener of unknown value fitted in its place brought the display back.[18] bobmoo79's parts list gives S10 as a 7.5 V zener (7.5B2).[4]
Display faults
[edit | edit source]Dark display, game otherwise running
[edit | edit source]The game logic and sound do not depend on the display or its transformer, so a game that plays its tunes with a dark display has a fault in the display supply, not in the microcontroller.[30] On the Astro Wars that means S06 first, then the transformer and, on a damaged board, S10 (see Known faults).[10][9][18] Measure for about −39 V on the display supply with the game running.[5]
Fading and dim areas
[edit | edit source]VFDs fade with use, unevenly, over years; the parts of the display lit most often fade first. A broken filament wire inside the tube leaves one area very dim. The Handheld Museum's administrator has never had one die outright unless the glass was broken.[30] MAME's notes also record that VFD colours fade after decades.[1]
Testing the tube out of the game
[edit | edit source]bobmoo79 checked his tube with bench supplies: about 3 V across the filament (display pins 1 and 30), then 12 V on one grid and one segment pin relative to the filament, lighting each segment in turn. He did not guarantee those voltages and would not run a tube on them for long.[3] He also proved a board's microcontroller and tube good, with S06 removed, by feeding −6 V to one filament pin from a second supply.[3]
| Function | Display pin | μPD553 pin |
|---|---|---|
| Filament | 1 and 30 | from the transformer |
| Grid 0 | 25 and 28 | 13 |
| Grid 1 | 29 | 12 |
| Grid 2 | 22 | 11 |
| Grid 3 | 20 and 21 | 10 |
| Grid 4 | 18 | 9 |
| Grid 5 | 16 | 8 |
| Grid 6 | 13 | 5 |
| Grid 7 | 10 | 4 |
| Grid 8 | 7 | 3 |
| Grid 9 (bottom row) | 4 | 2 |
The map was posted by bobmoo79, who credits it to another forum member, kevtris; the transformer connection for the filament is from bobmoo79's own tracing. It has not been checked against a second source.[3]
Broken tube
[edit | edit source]A cracked tube loses its vacuum and cannot be repaired; a replacement has to come from a scrapped Astro Wars or Galaxy II with the same display revision, B or D, because the two have different graphics.[9][1] One repairer checks the getter, the dark patch inside the glass: still black suggests the tube is intact, and he says a cracked tube turns whitish.[31]
Things that are not faults
[edit | edit source]- The display flickers on video. It is the camera's shutter, not visible in person.[15][8]
- The sound is loud and cannot be turned down or off.[24][22]
- The enemy squadron moves as soon as the game is switched on; play only starts on START.[11]
- The colours come from filter strips; the tube itself shows fewer colours.[23][1]
- At 5 V the game runs but the display is less bright than at 6 V.[19]
- After a repair S02 runs a little warm, not hot.[6]
What is realistically repairable
[edit | edit source]| Part | Status | Source |
|---|---|---|
| S02 (D882), S03, S06, S10 | Standard parts or proven substitutes; see above | [9][6][18] |
| Electrolytic capacitors | Standard parts | [4] |
| DC socket | Cleanable; replacement sockets are sold in repair kits | [16][9] |
| Switch contacts, pads, springs, cable joints | Clean, tension, resolder | [32][22] |
| Battery cover | 3D-printed or reproduction covers | [33][34] |
| Transformer | Donor part from another Astro Wars | [9] |
| Joystick rocker | Donor joystick board; new rockers hard to find | [34] |
| Display tube | Not repairable if broken; donor tube of the same revision (B or D) | [1][9] |
| Microcontroller (D553C 153) | Mask-programmed; donor only | [1][2] |
Before condemning the microcontroller or the display, check S06: one owner who never tested it gave up on a game whose new D882 smoked at 2.2 A, the S06 symptom.[12][3]
Related pages
[edit | edit source]- Grandstand Astro Wars
- Grandstand Astro Wars General Maintenance
- Grandstand Astro Wars Capacitor Replacement Guide
- Grandstand Scramble Troubleshooting Guide: the Epoch game with the same power circuit.
- Grandstand Universal Mains Adaptor
- Capacitor Failure Symptoms
References
[edit | edit source]- ↑ 1.0 1.1 1.2 1.3 1.4 1.5 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.
- ↑ 2.0 2.1 NEC Electronics USA, 1982 Microcomputer Catalog, data sheet "μPD552/μPD553 4-bit single chip microcomputers with vacuum fluorescent display drive capability", p. 165, Bitsavers copy on the Internet Archive. PMOS, 42-pin DIP, single −10 V supply; outputs that can be pulled to −35 V to drive a VFD directly; the μPD553 has 2000 × 8 mask ROM and 96 × 4 RAM.
- ↑ 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 3.17 3.18 3.19 3.20 3.21 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).
- ↑ 4.0 4.1 4.2 4.3 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.
- ↑ 5.0 5.1 5.2 5.3 5.4 5.5 5.6 5.7 5.8 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.
- ↑ 6.00 6.01 6.02 6.03 6.04 6.05 6.06 6.07 6.08 6.09 6.10 6.11 6.12 6.13 6.14 6.15 6.16 6.17 6.18 6.19 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).
- ↑ 7.0 7.1 7.2 7.3 7.4 7.5 7.6 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).
- ↑ 8.0 8.1 8.2 8.3 8.4 8.5 8.6 8.7 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).
- ↑ 9.00 9.01 9.02 9.03 9.04 9.05 9.06 9.07 9.08 9.09 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).
- ↑ 10.0 10.1 10.2 10.3 10.4 10.5 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).
- ↑ 11.0 11.1 11.2 11.3 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."
- ↑ 12.0 12.1 12.2 12.3 12.4 TheCod3r, "I Paid £50 For A Broken 1980s Grandstand Astro Wars Game! Can I FIX IT?", YouTube, 28 May 2023 (transcript read 2026-10-18). The board is marked "+6" and "GND" at the supply (3:14-3:41). After a damaged pad was repaired the D882 smoked; a new D882 drew 2.2 A at 6 V and smoked as well (12:08-20:03). He suspected the microcontroller or display and gave up; S06 was not checked (25:30-27:47).
- ↑ 13.0 13.1 13.2 Kip Hakes, "IT'S BURNING!!! A VERY poorly Astro Wars Tabletop Game", YouTube, 6 October 2023 (transcript read 2026-10-18). Sound but no display; the D882 smoked and reached 140 degrees on a thermal camera with the power switch bridged (2:52-10:20). The small transistor at S03 read in his tester as a C1841 (14:38). Replacing the D882 and S03 did not cure it (20:26).
- ↑ 14.0 14.1 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.
- ↑ 15.0 15.1 15.2 15.3 15.4 15.5 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).
- ↑ 16.0 16.1 16.2 16.3 16.4 16.5 16.6 16.7 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).
- ↑ 17.0 17.1 17.2 Repairing Faulty Tech, "REPAIRING a Grandstand Astro Wars with NO POWER", YouTube, 20 July 2024 (transcript read 2026-10-18). A dead game: 6 V reached the board and the transformer, but the power transistor read as a resistor in a component tester; the replacement got hot because it had been fitted the wrong way round; refitted correctly, the game worked (1:08-8:54).
- ↑ 18.0 18.1 18.2 18.3 18.4 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).
- ↑ 19.0 19.1 19.2 19.3 19.4 19.5 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.
- ↑ 20.0 20.1 20.2 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).
- ↑ 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.
- ↑ 22.0 22.1 22.2 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.
- ↑ 23.0 23.1 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).
- ↑ 24.0 24.1 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).
- ↑ 25.0 25.1 Retro4u, "Grandstand Astro Wars Repair", YouTube, 20 October 2025 (transcript read 2026-10-18). A dead game that smelled burnt: the power transistor had a hole blown in it; it and S06 were replaced from a bought kit of a transistor and a diode; the direction of S06 is marked on the board; adaptor 6 V centre negative (1:05-12:05).
- ↑ 26.0 26.1 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).
- ↑ 27.0 27.1 Wikipedia, "Astro Wars" (revision of 1 June 2025). Hardware section, without references: the D882 power transistor "is known to fail frequently", the S06 zener less often; isopropyl alcohol for button and switch contacts.
- ↑ 28.0 28.1 All About Circuits forum, "Grandstand Astro Wars Game (Faulty) identification", January 2020 (retrieved 2026-10-18). Two Astro Wars with the S06 fault: a BAT85 Schottky diode fitted in place of S06 "just burns it out"; 1N5275B 140 V zeners ordered on the strength of a YouTube comment then cured both: "the 1N5275B worked and now I have two playable Astro Wars units".
- ↑ 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.
- ↑ 30.0 30.1 Handheld Museum forum, "EPOCH Astro Command - dead or dying", January 2016 (retrieved 2026-10-18). Rik (site administrator): an Epoch VFD game will play and make its sounds even without the display or the small transformer that powers it; he has never had a VFD die unless its glass was broken; with heavy use the displays fade, unevenly, over years; a broken filament wire leaves an area of the display very dim; a dead game is normally a transistor or two blown by an incorrect power supply. The owner of the Astro Command (the Epoch version of Grandstand Scramble) found its supply runs from the control board to the main board through a flat cable, which frayed and broke after the board had been turned over repeatedly.
- ↑ 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).
- ↑ 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).
- ↑ 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.
- ↑ 34.0 34.1 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).