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Grandstand Invader From Space General Maintenance

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Epoch Invader From Space, Made In Japan, Copyright 1980 (Electronic Handheld Game)
Epoch's own Invader From Space. Grandstand's version has the same white case and controls, with GRANDSTAND ELECTRONIC GAME printed at the foot of the screen surround[1] (photograph Joe Haupt, CC BY-SA 2.0).

The Grandstand Invader From Space is Epoch's Invader From Space, made in Japan and sold in the UK by Grandstand from 1980.[2] Inside a white two-piece case are a main board carrying an NEC D552C 054 microcontroller and an NEC FIP9AM18T display tube, a small control board, a piezo speaker, a holder for four AA cells and an adaptor socket.[2][3][1] No service manual or schematic has been published. The advice here comes from Epoch's leaflet, MAME's notes on the hardware, and owners who have opened and repaired the game and published what they found. Fault-finding is on Grandstand Invader From Space Troubleshooting Guide.

The Invader From Space at a glance

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What is inside an Invader From Space
Part Detail Source
Boards Main board marked with the Epoch logo; small control board printed 36010-B; MAME gives the board labels as 36010 (A/B) [2][3]
Microcontroller NEC D552C 054 (μPD552, μCOM-44 family), with the game program in its own mask ROM; runs from a single −10 V supply [2][4]
Clock TDK FCR 400, a 400 kHz ceramic resonator [5]
Display NEC FIP9AM18T vacuum fluorescent tube (nine grids, cyan), under a blue, yellow and red overlay [2]
Display supply Power transistor S02 (NEC D882), a round TDK transformer marked TZ-91 at I01, diodes S04, S06 and S07, and electrolytic capacitors including C07 (330 µF 10 V) [3][1]
Sound Piezo disc on two leads, driven directly by the microcontroller [2][3]
Controls POWER slide switch, LEVEL and START buttons, FIRE button on a coil spring, intercept control lever (J01) [6][3]
Power Four AA cells; adaptor socket with a contact that disconnects the cells when a plug is inserted; Epoch rates the adaptor at 6 V DC, 200 mA; the Grandstand label asks for negative polarity [6][1][7]

Before you start

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  • Take the cells out and unplug any adaptor.
  • Tools: a cross-head screwdriver, a thin plastic pry tool, isopropyl alcohol, a soft brush, contact cleaner, a fibreglass pen for corroded contacts, and a multimeter. A bench supply set to 6 V lets you run the game without cells while you work on it; three of the repairers below used one.[7][8][9]
  • The game runs from 6 V, but the display supply on the main board makes a much higher voltage. NEC's microcontroller drives the display with outputs pulled to −35 V,[4] and on Grandstand Astro Wars (Epoch's Galaxy II), whose display supply is also built round a D882 and a transformer, an owner measured about 200 V peak to peak on the transformer winding.[10] Keep fingers off the transformer and the parts beside it while the game is switched on.
  • The only mains hazard is an old adaptor. Check its case and lead for cracks before plugging it into the wall, and see Grandstand Universal Mains Adaptor.

Opening the case

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  1. Take out the cells. Turn the game face down on a soft cloth.
  2. Remove the four cross-head screws in the back.[7][11]
  3. The front still will not come away: sticky pads at the display hold the two halves together. Work a thin pry tool round to free them slowly, and do not pull the halves apart.[7][8] On one Epoch unit the foam was stuck so firmly that the owner only bent the case far enough to reach the contacts.[11]
  4. Lift the front cover off. The buttons can drop out of the front cover at this point; collect them before turning it over.[8]
  5. The boards stay in the rear half with the cells. The main board, with the display tube lying along it, fills the left and centre; the battery holder runs down the right-hand side, the DC socket sits at the top right, and the 36010-B control board, with two pushbuttons, sits below the holder. Red and black leads run from the socket to the battery holder and on to the control board's + and − pads, and a bare four-wire link (L05) joins the control board to the main board.[3]
  6. The main board is held by small screws. Before lifting it, note how the leads to the socket, the battery holder and the speaker are routed, and do not flex the four-wire link: one of its wires broke on the Foxes Den unit.[1]

On reassembly, refit the buttons in the front cover, line the lever and the switch up with their slots, and replace the foam pads with thin double-sided foam if the old ones have perished.

The display tube

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The FIP9AM18T is a glass vacuum tube. Its lower end, where the sealed-off glass tip is, was found taped over in the exxos unit.[3] Do not press on the tube, rest the board on its face, or lever against the tip; a cracked tube lets air in and will not light again. MAME notes that the tube's own colour is cyan only: the blue, yellow and red of the invaders come from the coloured overlay in the front cover.[2]

Cleaning

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  • Case: wash the front and rear halves with warm water and a little washing-up liquid, away from the boards, and dry them. Retro Tech Repair used a toothbrush and window cleaner on the textured front.[7] Keep liquids off the printed screen surround and the base label.
  • Cracks: Foxes Den repaired a cracked surround from the inside with nylon soaked in superglue.[1]
  • Board: clean flux and dirt off with isopropyl alcohol and a soft brush. Where battery leakage has reached the board, clean it, check the tracks with a meter, and seal any copper you have exposed; Foxes Den used conformal coating.[1][5]
  • Window and overlay: wipe with a damp cloth only. The overlay is the only source of the invaders' colours.[2]

Batteries and the battery holder

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Epoch Invader From Space Instructions batteries and adaptor drawing
From page 3 of Epoch's leaflet: four AA cells in two rows, or an adaptor rated 6 V DC, 200 mA. No polarity is printed.
  • The game takes four AA cells, two to a row, with the + and − ends as marked in the holder.[6] The Grandstand base label recommends alkaline cells.[1][8]
  • Epoch's leaflet warns that the game "will not operate properly if batteries are weak": an erratic game or display means the cells should be checked or replaced first. Switch off after use and take the cells out for long storage.[6] One owner remembers it as a heavy user of cells.[12]
  • Clean green or white deposits off the springs and plates with contact cleaner and a fibreglass pen, and check that each spring is still firmly joined to its plate. On the StezStix unit the voltage reached the holder but not the edge of one spring, until he soldered the joint.[9] A unit that only works lying face down has a loose cell contact.[13]
  • A missing battery cover can be 3D-printed: Mike Underwood published one for this game in 2021 under CC BY 4.0.[14] The printed cover Foxes Den bought needed minor adjustment to fit.[1]

The adaptor socket

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The socket is on the top of the case, at the right.[12][3] It does two jobs: it takes the adaptor plug, and a contact inside it connects the cells to the game whenever no plug is inserted. Inserting a plug opens that contact.[7] When the contact corrodes or wears, the game still runs on an adaptor but is dead on batteries; this is the fault found in three of the repairs described on Grandstand Invader From Space Troubleshooting Guide.[7][8][9]

  • Spray contact cleaner into the socket and work a plug in and out a few times, then check with a meter that the battery voltage passes through the socket with no plug inserted.[9]
  • The socket can also work loose in the case. One owner's socket developed a wobble until the game would not stay on with the plug in.[12] Check that it is held firmly before blaming the board.
  • On Kip Hakes's Grandstand unit the negative wires go to the socket's centre terminal and the positive wires to the outer terminal.[8] That is a centre-negative socket, as the base label's "Negative Polarity" implies.[1]

Which adaptor

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  • Epoch rates the adaptor at 6 V DC, 200 mA and prints no polarity.[6] Grandstand's label asks for a Grandstand Universal Mains Adaptor set to negative polarity, with no voltage given.[1][8] A repair blog gives "5.5V@300mA" without a source.[1]
  • Use a regulated 6 V supply with a centre-negative plug. Retro Tech Repair checked that the centre pin of his bench lead was negative before plugging it in.[7]
  • A reversed adaptor can kill the game. An owner of Epoch's version lost his first one to a Radio Shack adaptor with the polarity set wrongly.[11] Measure any adaptor's output and polarity before connecting it.

Controls

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  • The POWER switch is a slider that bridges two contacts.[8] If the game only switches on at certain positions, clean the contacts; on an Epoch unit switching was "a little finicky" until it was cleaned.[11]
  • The 36010-B control board carries two pushbuttons, which sit under LEVEL and START on the front panel.[3][6] Clean the contact pads with isopropyl alcohol.
  • FIRE is a large button on a coil spring on the main board.[3][12] One owner's fire button had become sticky, with contacts so worn it had to be hammered.[13] Clean the pad and the contact under it.
  • The intercept control lever (J01) is a thin lever on the main board that moves left and right.[3][6] It is fragile: one owner's lever snapped.[12] Do not force it past its stops, and support it when the board is out.

Speaker

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The speaker is a piezo disc on two leads at the lower left of the case.[3] The game is loud, and it has no volume control or sound switch.[8][9][6] If the sound stops, look at the disc's solder joints and leads first: on the Retro Tech Repair unit the joint on the disc had oxidised and needed cleaning and fresh solder.[7]

Wearing parts

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What wears on an Invader From Space
Part What happens Check
Adaptor socket Battery contact inside fails, so the game runs only on an adaptor; socket works loose[7][8][9][12] Clean it; measure the battery voltage through it with no plug in
Battery springs and plates Corrosion; spring joint goes intermittent[9] Clean; resolder the spring if needed
Power switch Dirty contacts[11] Clean
FIRE button Sticky, worn contacts[13] Clean the pad and contact
Intercept lever Snaps[12] Handle gently
Four-wire link L05 A wire breaks[1] Check continuity; avoid flexing it
Electrolytic capacitors C07 found bulging and leaking[1] See the troubleshooting guide
Piezo speaker Joint oxidises[7] Clean and resolder

Storage

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  • Take the cells out.
  • Keep the game dry and out of direct sun, with the battery cover fitted.
  • Store it face up, so nothing presses on the lever.

Preventive maintenance checklist

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  1. Take out the cells and inspect the springs and plates.
  2. Measure the battery voltage at the holder and again on the far side of the adaptor socket, with no plug inserted.
  3. Measure any adaptor for 6 V and centre negative before using it.
  4. Open the case, look for bulging or leaking capacitors around C07 and for battery leakage on the board.
  5. Clean the power switch, LEVEL, START and FIRE contacts.
  6. Check the speaker's joints and the four-wire link.
  7. Reassemble with the foam pads in place and test at all three levels.
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References

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  1. ↑ 1.00 1.01 1.02 1.03 1.04 1.05 1.06 1.07 1.08 1.09 1.10 1.11 1.12 1.13 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.
  2. ↑ 2.0 2.1 2.2 2.3 2.4 2.5 2.6 2.7 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.
  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 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.
  4. ↑ 4.0 4.1 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 (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).
  5. ↑ 5.0 5.1 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.
  6. ↑ 6.0 6.1 6.2 6.3 6.4 6.5 6.6 6.7 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).
  7. ↑ 7.00 7.01 7.02 7.03 7.04 7.05 7.06 7.07 7.08 7.09 7.10 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.
  8. ↑ 8.00 8.01 8.02 8.03 8.04 8.05 8.06 8.07 8.08 8.09 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.
  9. ↑ 9.0 9.1 9.2 9.3 9.4 9.5 9.6 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.
  10. ↑ 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.
  11. ↑ 11.0 11.1 11.2 11.3 11.4 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".
  12. ↑ 12.0 12.1 12.2 12.3 12.4 12.5 12.6 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".
  13. ↑ 13.0 13.1 13.2 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.
  14. ↑ 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".


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