Grandstand Invader From Space Troubleshooting Guide
The Grandstand Invader From Space is Epoch's 1980 VFD tabletop game, sold in the UK by Grandstand.[3] No service manual or schematic has been published, so the fault tables below are built from repairs that owners have written up or filmed: Retro Tech Repair (2019),[4] Kip Hakes (2023),[5] StezStix Fix (2023),[6] Foxes Den (2025)[2] and a Handheld Museum forum thread (2019),[7] with Epoch's leaflet and NEC's data for the microcontroller. Opening the case, cleaning and the adaptor socket are covered on Grandstand Invader From Space General Maintenance.
The fault found most often is the adaptor socket: three of those five repairs found the game dead on batteries because of it.[4][5][6]
What should happen at power-on
[edit | edit source]- Slide POWER to ON. The game plays a short tune,[8] and the digital score readout shows "1": the game always starts at Level 1, the slowest of three speeds.[1]
- Each press of LEVEL steps the speed to 2 and 3, shown on the readout.[1]
- START begins the attack; the readout shows "5", the number of counterattack chances left, and one invader and one UFO appear.[1]
- To start a new game, switch off and on again; there is no reset button.[1]
- The sound is loud.[5][6]
Expected measurements
[edit | edit source]No manufacturer's figures exist for this board. These are the published ones.
| Point | Expected | Source |
|---|---|---|
| Battery holder, four fresh AA cells | About 6 V; 6.7 V was measured on one unit's holder | [1][6] |
| Bench supply in place of the cells | 6 V, centre negative if fed through the adaptor socket | [4][5][6] |
| After the adaptor socket, no plug inserted | The same as at the battery holder; nothing here means the socket's battery contact is open | [4][6] |
| Microcontroller supply, pin 21 (VSS) to pin 41 (VGG) | NEC specifies a single −10 V supply; 9.8 V was measured on a unit whose display lit | [9][7] |
| Clock | 400 kHz, from the TDK FCR 400 ceramic resonator | [7] |
| Display supply | No figures published for this game |
Symptom checklist
[edit | edit source]| Symptom | Likely cause | Action | Source |
|---|---|---|---|
| Dead on batteries, works on an adaptor | The adaptor socket's battery contact is open | Clean the socket and work a plug in and out; or fit another socket; or bypass it | [4][5][6] |
| Dead on batteries and on an adaptor, nothing hot | Corroded cell contacts; a broken spring joint; a broken wire in the link L05 | Clean the contacts; resolder the spring; check L05 for continuity | [6][2] |
| Dead; a small transistor near the transformer gets very hot; little voltage out of it | Shorted D882 power transistor at S02 | Replace the D882 | [6][2] |
| Dead; C07 beside the transformer bulging or leaking | Failed capacitor, and possibly a failed D882 as well | Replace C07 (330 µF 10 V), then test the D882 | [2] |
| Works only when laid face down | Loose cell contact | Clean and tighten the springs and plates | [10] |
| Switches off when the adaptor plug is moved | Socket loose in the case, or worn | Secure or replace the socket | [11][10] |
| Game plays but no sound | Speaker joint oxidised or speaker lead off | Clean and resolder the piezo disc's leads | [4][12] |
| Display lit and bright but shows only "8" at the top; no sound | Microcontroller not running | Check the clock and the −10 V supply; if both are good, the D552C 054 is the likely fault | [7] |
| Erratic play or erratic display | Weak cells | Fit fresh cells before anything else | [1] |
| FIRE needs hammering | Worn or dirty contact under the button | Clean the pad and contact | [10] |
| Power switch works only in some positions | Dirty switch contacts | Clean them | [13] |
| Dead after an adaptor was used | Reversed polarity | No repair of this damage has been published; start with the power transistor and the parts round the transformer | [13] |
Known faults on this game
[edit | edit source]The adaptor socket
[edit | edit source]The socket has a third contact that joins the cells to the game whenever no plug is inserted; inserting a plug opens it so that the adaptor does not feed the cells.[4] Three published repairs of dead games all came down to that contact:
- Retro Tech Repair found about 5.5 V on the red lead into the socket and none leaving it. The insertion-detect contact did not close to the sleeve. The game came up on a 6 V centre-negative bench supply plugged into the socket, and ran on batteries once the socket was replaced with one from a scrap Grandstand football game.[4]
- Kip Hakes ran the game from a 6 V bench supply, traced the fault to the socket, and soldered the positive lead past it, giving up the adaptor input.[5]
- StezStix Fix measured 6.7 V at the battery holder and nothing after the socket, took the socket out, found its switching contact unreliable, and cleaned it.[6]
To test, measure the battery voltage on the game side of the socket with no plug inserted. If it is missing, clean the socket first. A replacement must have the same switched contact and fit the hole in the top of the case; bypassing it leaves the game battery-only.
Power transistor S02 (D882) and capacitor C07
[edit | edit source]Two dead games were brought back by replacing the D882 power transistor in position S02:
- StezStix Fix, after clearing the socket and spring faults, found 6 V going into the board but only about 0.5 V coming out of a small transistor that ran at 50 to 80 °C and whose markings had gone. The D882 beside it gave inconsistent diode readings in and out of circuit. A new D882, with the original small transistor refitted, brought the game back.[6]
- Foxes Den found C07, a 330 µF 10 V electrolytic beside the transformer, bulging and leaking, and replaced it with the other three electrolytics. The game stayed dead until the D882 was replaced; it had given readings "all over the place".[2]
Test the D882 out of circuit as an NPN transistor. When fitting a 2SD882 or equivalent, match the pin order printed on the board (E, C, B).[2]
Microcontroller
[edit | edit source]The Handheld Museum thread describes a Grandstand unit with battery leakage on the board. All capacitors and transistors were replaced and the board cleaned, but the bright display showed only an "8" at the top and there was no sound. The supply between pins 21 and 41 was 9.8 V, and a Murata CSB400J fitted in place of the TDK FCR 400 resonator changed nothing, so the owner concluded the microcontroller had failed.[7] The D552C 054 holds the game in its own mask ROM, so the only replacement is the chip from another Invader From Space, Epoch or Grandstand.[3][9]
Power supply and display supply
[edit | edit source]The cells give 6 V, but the microcontroller needs about 10 V and the display more.[9][7] A converter on the main board, built round the D882 at S02 and a round TDK transformer marked TZ-91 at I01, makes the higher voltages; the Handheld Museum's administrator describes the transformer as the display's supply.[12][2][7] Diodes S04, S06 and S07 sit beside S02.[12] How the circuit is laid out has not been traced for this game. The display supply of Grandstand Astro Wars, also built round a D882 and a transformer, has been: there an owner measured about 200 V peak to peak on the transformer winding.[14] Keep fingers off the transformer on this board too while it is powered.
Capacitors
[edit | edit source]No capacitor list has been published. The values below are the only ones known. There is no separate capacitor guide for this game for that reason.
| Position | Value | Where | Source |
|---|---|---|---|
| C07 | 330 µF 10 V (found bulging and leaking; replaced with a 25 V part) | Beside the transformer at I01 | [2][12] |
| C08 | Not legible in the published photographs | Left of the display tube, about halfway down | [12] |
| C10 | Not legible | Top left corner of the main board | [12] |
| One more electrolytic | Not legible; label hidden | Just above C08 | [12][2] |
Two repairers replaced every electrolytic without curing the fault,[2][7] so new capacitors alone are unlikely to cure a dead Invader From Space. Replace a capacitor that bulges or leaks, clean the board under it, and go on to the D882. See Capacitor Failure Symptoms.
Display faults
[edit | edit source]The display is an NEC FIP9AM18T vacuum fluorescent tube with nine grids, glowing cyan; a coloured overlay gives the invaders their blue, yellow and red.[3] NEC's microcontroller drives it directly, with its output lines pulled to −35 V.[9]
| Symptom | Likely cause | Action | Source |
|---|---|---|---|
| No display, no sound, nothing at all | Power not reaching the board | Work through the socket, contacts, D882 and C07 above | [4][6][2] |
| Display lit but showing only one digit, no sound | Microcontroller or its clock | Check the 400 kHz resonator and the −10 V supply | [7] |
| Erratic display | Weak cells | Fresh cells | [1] |
| Colours paler than they should be | Age; MAME notes that VFD colours fade after decades | None; the overlay still gives the zones | [3] |
| Tube cracked, or will not light at all with good supplies | Air has entered the tube | Not repairable. The tube's segments are this game's own invader, UFO and missile-base shapes, so a replacement can only come from another Invader From Space | [1] |
No measurements of the display voltages have been published for this game, and no replacement tube is made. The tube's sealed glass tip is at its lower end; on one unit it had been taped over.[12] Handle the board by its edges.
Things that are not faults
[edit | edit source]- Filmed, the display flickers; to the eye it is steady.[5][4][6]
- Three bars on the score readout mean 1,000 points, the end of the game.[1]
- The game can end with chances left: it ends when an invader reaches the last position of the red zone, whatever the chances remaining.[1]
- The sound is loud, and there is no volume control or sound switch.[1][5]
- The tube glows cyan only; the zone colours come from the overlay.[3]
What can be repaired
[edit | edit source]| Part | Repairable? | Notes |
|---|---|---|
| Adaptor socket | Yes | Clean, replace, or bypass[4][5][6] |
| Cell contacts and springs | Yes | Clean and resolder[6] |
| D882 at S02, capacitors, diodes | Yes | Standard parts[6][2] |
| Link L05, speaker leads, dry joints | Yes | Resolder[2][4] |
| Battery cover | Yes | 3D-printed replacement[15] |
| Microcontroller D552C 054 | Only from another copy of the game | The program is inside the chip[3] |
| Display tube | Only from another copy of the game | No new tubes are made |
| Intercept lever | Only from a donor | It snaps[11] |
Related pages
[edit | edit source]- Grandstand Invader From Space
- Grandstand Invader From Space General Maintenance
- Grandstand Universal Mains Adaptor
- Grandstand Astro Wars
- Capacitor Failure Symptoms
- Battery Explosion, Capacitor or Corrosion Damage
References
[edit | edit source]- ↑ 1.00 1.01 1.02 1.03 1.04 1.05 1.06 1.07 1.08 1.09 1.10 1.11 Epoch Co. Ltd, Epoch's Invader From Space: The Game of Cosmic Combat, instruction leaflet, copyright 1980, made in Japan (Epoch Corporation, Englewood, New Jersey). Hosted here as File:Epoch Invader From Space Instructions.pdf: p. 2, power switch ("After each game turn switch to OFF and then back to ON to reset for a new game"), Level button (three speeds; the game starts at Level 1 and shows "1"), Start button, Intercept Control Lever; p. 3, Fire button, the four display zones, digital score readout, "Insert 4 AA batteries", the note that the game "will not operate properly if batteries are weak", that an erratic game or display means the batteries should be checked or replaced, and that they should be removed for long periods, and the A/C-D/C adapter drawing captioned "6-Volts DC, 200 ma" with no polarity shown; p. 5, game ending and scoring (1,000 points shown as three bars).
- ↑ 2.00 2.01 2.02 2.03 2.04 2.05 2.06 2.07 2.08 2.09 2.10 2.11 2.12 2.13 Balders, "Grandstand Invaders from space game", Foxes Den (repair blog), 15 March 2025 (retrieved 2026-10-18). A Grandstand unit bought dead on eBay, without its battery cover: C07 bulging on top and leaking underneath, with residue on the part beside it; C07 is "a 330uf 10v electrolytic capacitor"; the three other old electrolytics were replaced too; still dead after that; most of the board reflowed for dry joints; one wire of the link from the control panel to the main board had broken and was resoldered; the D882 power transistor gave readings "all over the place" and a new one brought the game back; conformal coating put on tracks with exposed copper after cleaning; a cracked case surround glued and reinforced with nylon and superglue; a 3D-printed battery cover needed minor adjustment. Photographs, examined at full size: the base label ("GRANDSTAND ELECTRONIC GAME. Uses 4 Penlight Batteries. Alkaline type recommended. For mains operation use a GRANDSTAND Universal Mains Adaptor. Negative Polarity. Made in Japan."); the front with "GRANDSTAND ELECTRONIC GAME" on the screen surround; the opened game; C07 beside the TDK transformer at I01; the NEC D882 in position S02 (pads E, C, B); the four-wire link L05. The post also says the game used a "Grandstand 5.5V@300mA power adapter", without giving a source.
- ↑ 3.0 3.1 3.2 3.3 3.4 3.5 MAME source, hh_ucom4.cpp at commit d404316 (retrieved 2026-10-18). Driver notes for Epoch Invader From Space, written from a real board: made in Japan; PCB labels 36010(A/B); NEC uCOM-44 microcontroller labelled D552C 054, 1-bit sound; cyan VFD NEC FIP9AM18T, tube no. 0D; colour overlay making alien rows 1 and 2 blue, 3 and 4 yellow and row 5 red; releases by Epoch (USA) and Grandstand (UK); the file's chip list dates the D552C 054 to 1980. The 1 KB (0x400) program dump is read from the D552C 054 itself. The file header explains NEC's FIP part numbers (the first figure is the number of grids) and notes that VFD colours fade after decades.
- ↑ 4.00 4.01 4.02 4.03 4.04 4.05 4.06 4.07 4.08 4.09 4.10 4.11 Retro Tech Repair, "Grandstand Invader From Space Game Repair and Restore - Retro Games", YouTube, 15 January 2019 (watched through its transcript, retrieved 2026-10-18). Sold as working only from an adaptor; dead on batteries; four Phillips screws in the back, then sticky pads glued to the back of the display that had to be prised away; switch bridged with a jumper; about 5.5 V arrived on the red wire at the DC socket but did not pass through it; with no plug inserted the socket's insertion-detect contact should short to the sleeve and did not; the game came up on a 6 V bench supply with the centre pin negative plugged into the socket; the socket was replaced with one taken from a scrap Grandstand football game and the game then ran on batteries; no sound until the piezo sounder's dull, oxidised solder joint was cleaned with a fibreglass pen and resoldered with flux; case cleaned with a toothbrush and window cleaner.
- ↑ 5.0 5.1 5.2 5.3 5.4 5.5 5.6 5.7 5.8 Kip Hakes, "Repairing a Grandstand Invader from Space from eBay! - Fix it Friday", YouTube, 18 August 2023 (watched through its transcript, retrieved 2026-10-18). Reads the base label ("uses four penlight batteries, alkaline type recommended; for mains operation use a Grandstand Universal Mains Adaptor, negative polarity"); sticky pads hold the front after the screws are out; the power switch is a slider over two contacts; dead on batteries; with 6 V from a bench supply he traced the fault to the DC socket and bypassed it by soldering the positive lead past it; the socket had the negative wires on its centre terminal and the positive wires on its outer terminal; black staining on the board of unknown cause; "very loud"; the camera shows the display flickering, the eye does not.
- ↑ 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 StezStix Fix, "A VIEWER sent me this Broken INVADER FROM SPACE Game | Can I FIX It?", YouTube, 30 September 2023 (watched through its transcript, retrieved 2026-10-18). A unit found dead in a loft: 6.7 V at the battery holder but not past the DC socket, whose contacts were cleaned rather than bypassed; an intermittent connection at the edge of a battery spring, secured with solder; then 6 V into the board but only about 0.5 V out of a small transistor that ran at 50 to 80 °C, its markings gone; the D882 beside it gave inconsistent diode-test readings in and out of circuit; with a new D882 fitted and the original small transistor refitted, the game ran from a 6 V bench supply and then reassembled; very loud.
- ↑ 7.0 7.1 7.2 7.3 7.4 7.5 7.6 7.7 7.8 Handheld Museum forum, "Invaders from Space repair", December 2019 (retrieved 2026-10-18). A Grandstand unit with battery leakage on the board: all capacitors and transistors replaced and the board cleaned, but the display, though bright, showed only an "8" at the top and there was no sound; 9.8 V measured between pins 21 and 41 of the microcontroller; the owner identified the 400 kHz ceramic oscillator/filter as a TDK FCR 400 and the round component as the TDK transformer; a Murata CSB400J 400 kHz part fitted in its place made no difference; the site administrator (Rik) noted that the display lighting at all meant the transformer was working and that each game's microcontroller is specific to it; unresolved.
- ↑ ArcadeUSA, "Epoch's Invader From Space!", YouTube, 9 February 2019 (watched through its transcript, retrieved 2026-10-18). An Epoch-branded unit: four AA cells behind the back; it plays a tune when switched on; LEVEL selects the difficulty before START; "freaking loud".
- ↑ 9.0 9.1 9.2 9.3 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 (retrieved 2026-10-18). The μPD552 has a 1000 × 8-bit ROM and 64 × 4-bit RAM; it is a PMOS part in a 42-pin DIP running from "a single −10 V power supply"; 27 of its port lines "are capable of being pulled to −35 V in order to drive Vacuum Fluorescent Displays directly"; pin 21 is VSS (supply positive) and pin 41 VGG (supply negative). The family's clock is a ceramic resonator and two capacitors on the CL0 and CL1 inputs (p. 145).
- ↑ 10.0 10.1 10.2 Mamemeister, "Mamememeister's LCDs - 'Invader From Space'", YouTube, 23 April 2014 (watched through its transcript, retrieved 2026-10-18). A Grandstand unit that would only work on batteries lying face down; run on an adaptor whose lead had to be held down to keep the game on; the fire button "a bit sticky", with worn contacts that had to be hammered.
- ↑ 11.0 11.1 Retro Arcadia, "My Life With… Grandstand Invader From Space Handheld Electronic Game", 25 September 2024 (retrieved 2026-10-18). Owner's recollection: the battery compartment towards the top makes it top-heavy; it "gobbles batteries"; the fire button has "a meaty click"; the intercept control lever is flimsy and snapped on his first unit; the adaptor socket on the top "soon developed a wobble" until the game would no longer stay on with the plug in; the Grandstand blurb "Uses 4 x Penlight size HP7/AA batteries or Grandstand Universal Game Mains Adaptor".
- ↑ 12.0 12.1 12.2 12.3 12.4 12.5 12.6 12.7 Icky, "Grandstand Invader From Space - Hand Held Game", exxos forum, 26 March 2024 (retrieved 2026-10-18). A boxed Grandstand unit that worked except for the sound; another member suggested a speaker wire had been pulled off. The photograph of the opened game (IMG_3640, 800 × 1067 pixels), examined at full size: the brown main board with the Epoch logo, the display tube lying along it with tape over its lower end; the TDK transformer marked TZ-91 at I01 with C07 beside it; electrolytics at C08 and C10; transistor S02 with diodes S04, S06 and S07 beside it; the piezo speaker disc at lower left on two leads; the FIRE button's coil spring and the intercept lever (J01) at the bottom of the main board; the battery holder along the right-hand side; the DC socket at the top right, wired with red and black leads; a small grey control board printed 36010-B carrying two pushbuttons and the battery leads' + and − pads, joined to the main board by the four-wire link L05.
- ↑ 13.0 13.1 Glen's Retro Show, "Invader From Space", YouTube, 26 August 2016 (watched through its transcript, retrieved 2026-10-18). An Epoch-branded unit; the owner's childhood game stopped working when he used a Radio Shack adaptor with the polarity set wrongly ("it popped something"); four screws in the back; old foam inside was stuck so firmly that he opened the case only far enough to clean the contacts; switching on and off was "a little finicky" until he cleaned "the power connector".
- ↑ Handheld Museum forum, "Astro wars / galaxy ii repair", pages 1 and 2, December 2018 to January 2019 (retrieved 2026-10-18). The dead Astro Wars in this thread had its D882 power transistor running hot; another member describes the circuit as switching 6 V on and off rapidly into the transformer. On a working Astro Wars (Epoch Galaxy II hardware), measured with a basic self-built oscilloscope that the owner said was probably not accurate at that level: the transformer gives an AC signal of about 200 V peak to peak, period 10 µs, at the cathode of diode S06 (transformer pin 1), and about −39 V DC at the diode's other end.
- ↑ Mike Underwood (saint_mikie), "Grandstand Invaders From Space Battery Cover", Thingiverse 4888078, 17 June 2021, CC BY 4.0; mirrored on the Internet Archive as thingiverse-4888078 (retrieved 2026-10-18): "Replacement Battery Cover for the Grandstand Invaders From Space, 1980 hand held video game".