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Grandstand TV Game 2000 General Maintenance

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Grandstand Adman TV Game 2000 (5)
A TV Game 2000 with its base removed. The board, marked GAMATIC-7600 on its solder side, is screwed to the upper case at its four corners; the KDC modulator is on its metal plate at the left and the speaker below the board.

The Grandstand TV Game 2000 is a black-and-white, four-game Pong console made in Korea and sold by Adam Imports under the Adman Grandstand name from 1977. Its board is the Gamatic 7600 design, which was sold under several other names, and the game itself comes from a single Texas Instruments TMS1965NL chip.[1][2] The consoles are now close to 50 years old. No Grandstand service manual, schematic or parts list has been found. The sources here are the console's own instruction leaflet, photographs of one opened console with its owner's notes, and the published pin table and application circuit for the TMS1965. That console no longer works because one of its electrolytic capacitors burst.[3]

Fault-finding is on Grandstand TV Game 2000 Troubleshooting Guide, and the burst capacitor is covered on Grandstand TV Game 2000 Capacitor Replacement Guide.

The TV Game 2000 at a glance

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What is inside a TV Game 2000
Part Detail Source
Game chip Texas Instruments TMS1965NL, date code KA 7740 [2]
Other IC RCA CD4071BE (CMOS quad 2-input OR gate) [2]
Board Single-sided; solder side marked GAMATIC-7600 and WK-I HB [4][3]
Supply 9 V DC from six UM-2 (C, LR14) cells, or a 9 V adaptor in the rear socket; 360 mW moulded on the base [5][3]
Adaptor socket Rear, labelled AC 9V ADAPTOR; centre negative according to the owner; plugging in disconnects the cells [6][3][7]
RF modulator KDC UM-1111E 30 can on a metal plate; UHF channel 30; 75 Ω coaxial lead [4][7]
Adjustment HORI-HOLD, through a hole in the rear panel (HORI LOCK in the leaflet) [6][7]

Before you start

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  • Take the six cells out and unplug the adaptor before opening the case.
  • You need a cross-head screwdriver, isopropyl alcohol, a soft brush, a contact cleaner made for switches and potentiometers, and a multimeter.
  • Nothing inside runs at more than 9 V. The mains hazard is an old adaptor: a cracked case or a perished lead can put mains voltage within reach of a finger. Check any adaptor before plugging it into the wall.
  • One TV Game 2000 has already had an electrolytic capacitor explode inside the case.[3][8] Wear eye protection the first time you power up a console that has been stored for years and has not been recapped.

Opening the case

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Grandstand Adman TV Game 2000 (8)
The base: battery cover with its two OPEN tabs, the model label, the 360 mW moulding at the left and a rubber foot at each corner, with the case screws recessed inside the feet.

The board, the modulator, the speaker and the switches are all fixed to the upper half of the case. The base, with the battery cover in it, is the part that comes off.[3][4]

  1. Remove the battery cover on the base; it has two tabs marked OPEN. Take the cells out.[5]
  2. Turn the console over onto a soft cloth, with the two control boxes in their recesses so that the coiled leads are not stretched.
  3. Remove the four case screws. The leaflet's bottom view shows them at the four corners; on the photographed console they sit down inside the rubber feet.[7][5][3]
  4. Lift the base slowly and look for any wires running between the two halves before pulling it clear. The solder side of the board now faces you.[3][4]
  5. If you need the component side, photograph the wiring first and then remove the four screws at the corners of the board. Every connection to the modulator, speaker, switches and control boxes is a soldered flying lead with no plug, so turn the board over gently and do not let the leads take its weight.[4]

The modulator sits on a metal plate held by two screws, and the slide switches are mounted on metal brackets along the top edge. Each control-box lead enters the case through a metal clamp held by two screws, which takes the strain off the solder joints.[4] Refit the clamps before closing the case.

Cleaning

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  • Wipe both halves with a cloth dampened in warm water and a little washing-up liquid. Do not soak them: the board and switches stay fixed to the upper half. Keep liquid off the battery contacts, the printed control-panel plate and the base label.
  • Clean the board with isopropyl alcohol and a soft brush. On the photographed console, fibrous debris from the burst capacitor is spread over both sides of the board and through the case, and the owner found it hard to remove.[3][4][2] If you find the same, remove every trace, then look at the copper and the parts underneath for corrosion. Battery Explosion, Capacitor or Corrosion Damage describes how to neutralise and clean electrolyte residue.
  • Clean the contacts of the AC 9V ADAPTOR socket and the plug on the end of the RF lead.

Power: cells, socket and adaptor

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  • The console takes six 1.5 V UM-2 cells (C size, LR14) in a compartment behind the battery cover on the base. Fit them the way round marked in the compartment. On the photographed console the serial-number label is inside the compartment.[7][5][3]
  • The base label and moulding give 9 V DC and 360 mW, which is 40 mA. Game Tech Wiki gives the same 9 V, 40 mA and 360 mW for the Intel TV Sport 1004, another Gamatic 7600.[5][9]
  • The leaflet warns owners to use only the Adman 2000 TVG adaptor, because "failure to use this approved adaptor may cause damage to your set". It gives no polarity, and neither does the console. The owner of the photographed console gives the socket as centre negative.[7][3] Before connecting any adaptor, measure which contact of the socket goes to the battery compartment's positive terminal, then measure the adaptor's plug. Old unregulated 9 V adaptors can read well above 9 V with no load.
  • Plugging in the adaptor disconnects the cells.[7] The socket therefore has a switching contact, which is a wearing part: if the console runs on the adaptor but not on cells, look there first.
  • The Grandstand Universal Mains Adaptor was sold for Grandstand's handheld and tabletop games, with a 6-9 V output and a polarity switch.[10] No source links it to the TV Game 2000. If you use one, measure its plug at the 9 V setting before connecting it.

Take the cells out whenever the console is put away. Leaking C cells corrode the springs and can run into the case.

Controls and control boxes

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Grandstand Adman TV Game 2000 (4)
The right-hand control box. Its coiled lead enters the side of the box and runs on into the side of the case. Check the insulation at both points.

The panel carries POWER, SPEED (fast or slow), AUTO SERVE (on or off), a GAME SELECTOR lever for football, squash, tennis and practice, ANGLE (20° or 40°) and BAT SIZE (large or small). Each control box has a BAT CONTROL knob and a red button, SERVE on the left box and RESET on the right.[11][1]

Slide switches and the game lever

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In the application circuit published for the TMS1965, each setting is a switch from one pin of the chip to ground, and the game selector grounds one of the game pins.[12] A dirty contact therefore gives the wrong setting or the wrong game. Spray a little switch cleaner into each switch and work it from end to end a dozen times.

Bat controls

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Each knob turns a potentiometer. The published TMS1965 circuit uses 1 MΩ, with 10 kΩ in series and a 0.1 µF capacitor on the chip's bat input; the values fitted to the 2000 have not been read.[12] A dirty track makes the bat jump; clean it with a potentiometer cleaner and turn the knob end to end twenty or thirty times. No photograph of the inside of a 2000 control box has been found, so note how it comes apart as you open it.

Coiled leads

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The leads are wired in permanently. Each one leaves the side of the case, runs as a coiled lead and enters the side of its control box.[3][13] Check both ends for cracked insulation and, with a multimeter, for broken conductors while flexing the lead.

RF output and the HORI-HOLD control

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  • The leaflet says the game is designed for channel 30 and that the picture goes out through a 75 Ω coaxial cable; the modulator is labelled UM-1111E 30.[7][4] Use a television or video recorder with an analogue UHF tuner and tune it by hand around channel 30.
  • The HORI-HOLD control is reached through a hole in the rear panel.[6] The owner describes it as adjusting the displacement of the picture.[3] If the picture will not hold steady after fine-tuning the television, turn it slowly with a plastic trimming tool, and note where it started.
  • The RF lead is fixed. Check it for kinks and for a broken screen where it leaves the case.
  • Not every Gamatic 7600 is built the same way. An Olympos-badged Gamatic 7600 in the same case has a phono RF OUT socket and a switch for VHF channel 3 or 4 on the rear, where the Grandstand has its fixed lead.[14] Check that a donor board or modulator from another brand's Gamatic 7600 matches yours before using its parts.

What wears, and what to check

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Wearing parts on the TV Game 2000
Part What happens Check
Electrolytic capacitors One burst on the photographed console and stopped it working[3][8] Look for split, domed or leaking cans and for debris; see Grandstand TV Game 2000 Capacitor Replacement Guide
Adaptor socket switching contact Disconnects the cells when a plug is in[7] Run the console on cells with no plug in the socket
Slide switches and game lever Open contacts in plastic housings Clean and work each one
BAT CONTROL potentiometers Dirty or worn tracks Clean; measure end to end
Coiled leads Fixed at both ends[13] Flex-test each lead
Battery springs Corrode if cells are left in Clean; remove cells for storage

Test points

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The TMS1965's pins as published by Facele. Take the readings with the console switched on and the meter's common lead on pin 2.[12]

TMS1965 test points
Pin Function Expected
2 VSS (earth) Reference
4 Supply 6 to 7 V
17 Clock input 2 MHz
3 Sound output Activity each time the console beeps
16 Sync output Pulses while running
25 Reset Changes only while RESET is pressed

Facele gives 6 to 7 V for the chip's supply, against 9 V on the base label, so the board must reduce the supply before it reaches pin 4. That part of the 2000's circuit has not been traced. A reading between 6 and 7 V on pin 4 shows that it is doing its job.[5][12]

Storage

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  • Remove the cells.
  • Keep the console dry and away from heat, with the control boxes in their recesses.
  • Coil the RF lead loosely.

Preventive maintenance checklist

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  1. Remove the cells; check the springs for corrosion.
  2. Measure the adaptor's voltage and polarity, and the socket's polarity, before connecting them.
  3. Open the base and look at every electrolytic capacitor for bulging, splits or leakage.
  4. Clean the board of any debris or residue.
  5. Clean the slide switches, the game lever and the two BAT CONTROL potentiometers.
  6. Flex-test the two coiled leads.
  7. Tune an analogue television to channel 30 and check the playfield, the scores and both bats.
  8. With the console running, measure pin 4 of the TMS1965.
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References

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  1. ↑ 1.0 1.1 HomeComputerMuseum (Helmond), "Gamatic 7600" (retrieved 2026-10-18): the Gamatic 7600 was "sold worldwide under many brands, as the Grandstand T.V. Game Model 2000 for example, or the Univox 41 N"; board labelled "F'GAMATIC-7600"; controllers with a dial and a red button each, serve on the left and reset on the right; ball speed, automatic serve, game, rebound angle and paddle size switches; six CM2 cells or an external 9 V DC supply, 360 mW; TMS-1965 chip.
  2. ↑ 2.0 2.1 2.2 2.3 Photograph by José Antonio Ortigueira Amor, File:Grandstand Adman TV Game 2000 (6).jpg (CC BY 4.0, from Wikimedia Commons), and the larger copy of the same view on the owner's blog, examined at full size: component side of the board with "TMS1965NL KA 7740" (Texas Instruments logo), "CD4071BE RCA 707", a transistor marked 9016, a black trimmer at the board edge, a metal can, a large lavender electrolytic of which only "85°C" can be read, three white and two small lavender electrolytics whose values cannot be read, and fibrous debris over the board.
  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 3.13 José Antonio Ortigueira Amor, "Adman Grandstand TV Game 2000 (WK-I HB) (1977)", Retro Ordenadores Orty (collector's blog, in Spanish), 7 November 2023 (retrieved 2026-10-18). The owner's description of his console: Texas Instruments TMS1965NL and RCA CD4071BE on the board; control boxes permanently wired, their leads leaving the left and right sides of the case, SERVE on the left box and RESET on the right; rear socket "AC 9V ADAPTOR" for an external 9 V DC supply, centre negative; a rear "HORI-HOLD" control for adjusting the displacement of the picture; RF lead for UHF channel 30; six 1.5 V LR14 cells in an internal compartment reached through the lower case, with the serial-number label inside it; four screws hold the lower case, and removing it exposes the back of the board, marked GAMATIC-7600 and WK-I HB. The console does not work: a capacitor near the left side of the board, to the left of the other capacitor, exploded, scattered its contents through the inside of the console (hard to clean, and some remains on the board) and knocked a resistor off its solder pads.
  4. ↑ 4.0 4.1 4.2 4.3 4.4 4.5 4.6 4.7 Photograph by José Antonio Ortigueira Amor, File:Grandstand Adman TV Game 2000 (5).jpg (CC BY 4.0, from Wikimedia Commons), examined at full size: the upper case from inside with the base removed. The board, solder side outwards, is screwed to the case at its four corners; the KDC UM-1111E 30 modulator sits on a metal plate held by two screws; slide switches are mounted on metal brackets along the top edge; each control-box lead enters through a metal clamp held by two screws; the speaker is below the board; all connections are soldered flying leads; fibrous debris is scattered across the board and the case.
  5. ↑ 5.0 5.1 5.2 5.3 5.4 5.5 Photograph by José Antonio Ortigueira Amor, File:Grandstand Adman TV Game 2000 (8).jpg (CC BY 4.0, from Wikimedia Commons), examined at full size: the base, with the battery cover and its two tabs marked OPEN, the label "ADMAN GRANDSTAND / TV GAME 2000 / POWER SUPPLY: 9V-DC (6xUM-2 BATTERY) OR AC ADAPTER 9V / MADE IN KOREA", the moulding "POWER CONSUMPTION 360mWATT, 9V DC", and a rubber foot at each corner with a screw recessed inside it.
  6. ↑ 6.0 6.1 6.2 Photograph by José Antonio Ortigueira Amor, File:Grandstand Adman TV Game 2000 (1).jpg (CC BY 4.0, from Wikimedia Commons): the rear panel, with the RF lead at the left, a hole labelled "HORI - HOLD" and a socket labelled "AC 9V ADAPTOR" at the right.
  7. ↑ 7.0 7.1 7.2 7.3 7.4 7.5 7.6 7.7 7.8 Adman, TV Game Model 2000 instruction leaflet, pages 2 and 3, as photographed by José Antonio Ortigueira Amor and published (CC BY 4.0) on Retro Ordenadores Orty, 7 November 2023 (retrieved 2026-10-18). Figure 1 (top, rear and bottom views) with fifteen numbered parts, among them 2 manual serve button, 9 reset button, 10 control box, 11 bat control, 12 speaker, 13 "9V ADAPTOR JACK", 14 "HORI LOCK" and 15 battery cover; the bottom view shows four fixings at the corners. Features: score shown on the screen from 0 to 15; "Dual power system: 6 x 1.5V UM cell or external 9V AC adaptor"; "Video signal supplied through 75 ohm coaxial cable". Warning: use only the Adman 2000 TVG adaptor, because "failure to use this approved adaptor may cause damage to your set". Operating procedure: open the battery cover on the bottom cabinet and insert six UM 1.5 V cells; the adaptor plug goes into jack 13, and "this connection of the adaptor disconnects internal battery supply"; the game "is designed for use on channel 30".
  8. ↑ 8.0 8.1 Photograph by José Antonio Ortigueira Amor, File:Grandstand Adman TV Game 2000 (7).jpg (CC BY 4.0, from Wikimedia Commons), with the photographer's description "Exploded and detached capacitor (together with a resistor)", examined at full size: a lavender-sleeved capacitor printed "SAMHWA" and "470µF16V" with a negative-lead arrow and brown stains on the sleeve, a crumpled grey mass, and a resistor whose body is charred so that its colour bands cannot be read.
  9. ↑ Game Tech Wiki, "INTEL (INTerELektronik GmbH)", section "Intel TV Sport 1004 (D-670/37)" (retrieved 2026-10-18). Community wiki: the Intel TV Sport 1004 "was also called the Gamatic 7600"; board labelled "F'GAMATIC-7600"; TMS-1965; power supply "AC/DC 9v 40mA 360mW or 6x1.5v "C"(R12) batteries".
  10. ↑ Handheld Museum, "Grandstand Universal Mains Adapter" (retrieved 2026-10-18). Collector's entry: model UGT, "AC adapter sold by Grandstand in England/U.K. for their handheld/tabletop games", for 240 V mains, with a switch that toggles the polarity and turns the output off; output 6-9 V DC at 1.5 VA.
  11. ↑ Photograph by José Antonio Ortigueira Amor, File:Grandstand Adman TV Game 2000 (3).jpg (CC BY 4.0, from Wikimedia Commons): the control panel (POWER ON/OFF, SPEED FAST/SLOW, AUTO SERVE ON/OFF, GAME SELECTOR lever for FOOTBALL, SQUASH, TENNIS and PRACTICE, ANGLE 20°/40°, BAT SIZE LARGE/SMALL) and the two control boxes, each with a BAT CONTROL knob and a red button labelled SERVE on the left box and RESET on the right.
  12. ↑ 12.0 12.1 12.2 12.3 Facele (Texas Instruments collectors' museum, Rieti), "TMS1965" (retrieved 2026-10-18). Pin table for the TMS1965: pin 2 VSS (earth), pin 4 supply, "the voltage must be between 6 and 7 Volt", pin 3 sound output, pin 16 sync output, pin 17 2 MHz clock input, pins 9 and 10 right and left player outputs, pin 6 ball output, pin 24 score and field output, pins 11 and 12 right and left bat inputs, pin 5 ball angle, pin 7 ball speed, pin 8 manual serve, pin 13 bat size, pins 18 to 23 game select, pin 25 reset, pins 26 and 27 shot and hit, pins 1, 14, 15 and 28 not connected; described as pin-compatible with the AY-3-8500. The page also shows an application circuit for the "TMS 1965 NLA": a 10 µF capacitor across the supply; each bat set by a 1 MΩ potentiometer with 10 kΩ in series, a 220 Ω resistor and a 0.1 µF capacitor; game, angle, speed, serve, bat-size and reset switches to ground; a 2 MHz oscillator; the sound output driving an 8 Ω speaker through a 2N2222 transistor, 15 kΩ, 0.2 µF and 51 Ω; the video outputs combined in TP4072 OR gates and a 330/510/220/510 Ω resistor network to the modulator.
  13. ↑ 13.0 13.1 Photograph by José Antonio Ortigueira Amor, File:Grandstand Adman TV Game 2000 (4).jpg (CC BY 4.0, from Wikimedia Commons): the right-hand control box, its coiled lead entering the side of the box and continuing straight into the side of the case.
  14. ↑ Retrocomputers.gr, "Olympos Electronic Gamatic 7600" (photo album, 22 photographs, retrieved 2026-10-18): an Olympos-badged Gamatic 7600 in the same case as the TV Game 2000, with the base label "Olympos Electronic Co., Ltd. MODEL NO.: GAMATIC 7600", the moulding "POWER CONSUMPTION 360mWATT, 9V DC", rear labels "HORI - HOLD" and "AC 9V ADAPTOR", and, where the Grandstand has a fixed RF lead, a phono socket and a two-position switch labelled "RF OUT CH4 CH3". Exterior photographs only.


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