Jump to content

Grandstand TV Game 2600 Mk II Troubleshooting Guide

From RetroTechCollection
Adman Grandstand 3600 MK II Colour (2)
The hand controllers and Thundercolt gun as supplied with the colour 3600 Mk II. The Centre for Computing History's 2600 Mk II has the same style of controllers and the same gun model; no freely licensed photograph of a 2600 Mk II has been found.

Fault-finding for the Grandstand TV Game 2600 Mk II, the black-and-white Grandstand Pong console of 1977 with a Thundercolt light gun.[1] No repair report, manual or inside photograph of a 2600 Mk II has been found, and its game chip has not been identified. Its panel, game key, hand controllers and gun match the colour Grandstand TV Game 3600 Mk II, which uses General Instrument's AY-3-8500,[2][3] so the AY-3-8500 checks below are a starting point, to be confirmed against the chip actually fitted. Opening the case and routine care are on Grandstand TV Game 2600 Mk II General Maintenance.

What should happen at power-on

[edit | edit source]
  • A black-and-white picture of the game set on the two GAME SELECT switches: tennis (A-B), football (A-D), squash (B-C) or practice (C-D).[2][4]
  • Each hand controller moves its bat up and down.
  • With BALL SERVE on AUTO the ball serves itself; on MANUAL the game waits for SERVE after each point. RESET clears the scores.[2][5]
  • The target games (TARGET 1-B and TARGET 2-D) are played with the light gun.[2][1] On the 3600 Mk II they appear only once the gun is plugged in;[6] expect the same on the 2600 Mk II if it has the same sockets.

Expected measurements

[edit | edit source]
Reference values
Point Expected Source
Supply As printed on the base label; not published
If the chip is an AY-3-8500: pin 4 to pin 2 +6 to +7 V [5]
If the chip is an AY-3-8500: pin 17 2.012160 MHz ±1% [5]
Closed switch contact to ground 1 kΩ or less on an AY-3-8500 [5]

Identify the chip before relying on the AY-3-8500 values. Texas Instruments' TMS-1955 and TMS-1965 are pin-compatible with it,[7] so the same pins are a reasonable first guess for either family.

Symptoms

[edit | edit source]
2600 Mk II symptoms
Symptom Likely cause Action Source
Dead Cells or adaptor; POWER switch; supply section Check the supply against the base label, then follow it through the POWER switch to the game chip.
Snow on the television Tuning; no analogue tuner; RF lead Tune slowly across the UHF band. Check the RF lead.
One bat missing or jumping Hand controller or its socket Swap the two controllers between LEFT PLAYER and RIGHT PLAYER. A fault that moves is in the controller. [2]
Football with a third bat on the right No game selected: a GAME SELECT contact is open On the AY-3-8500, selecting no game gives an undocumented seventh game, Handicap, with a third bat for the right-hand player. Clean the A/C and B/D switches. [7]
A setting has no effect Dirty slide switch Clean it and measure the closed contact. [5]
Target games missing, or the gun never scores Gun not plugged in, plug or socket dirty, flat-panel television, lens or trigger Plug the gun in and test on a CRT television. Clean the plug, the sockets and the lens. On an AY-3-8500 the gun pulses pins 26 and 27. [6][5]
The game stops after every point BALL SERVE set to MANUAL Press SERVE, or set AUTO. [2][5]
Scores will not reset RESET contact Clean the button contact. [2]

Known faults reported for this device

[edit | edit source]

None. The Centre for Computing History's record describes a complete example with its controllers and gun and reports no fault.[1] No forum thread, blog post or repair account for a 2600 Mk II has been found.

The Wikipedia list of Grandstand consoles links its 2600 Mk II row to a South-West Retro Computing Archive item, but that item is a colour 3600 Mk II.[4][8] Photographs reached from that link therefore show the wrong model.

Things that are not faults

[edit | edit source]
  • The picture is black and white.[4]
  • On MANUAL serve the game waits after each point.[5]
  • The light gun will not score on a flat-panel television.
  • The Centre for Computing History lists four games, counting the target shooting as one;[1] the panel's game key has six.[2]

What is realistically repairable

[edit | edit source]
Repairability of 2600 Mk II parts
Part Repairable? Notes
Hand controllers Yes They plug in, so a spare can be tried at once.[2]
Slide switches, buttons, sockets Yes Clean first.
Light gun Yes The body is screwed together.[2]
Board parts Yes, once identified No values or chip type have been published. Photograph and record before replacing anything.
Game chip Only by transplant If it is an AY-3-8500, donors are common: the chip was used in hundreds of consoles.[7]
[edit | edit source]

References

[edit | edit source]
  1. ↑ 1.0 1.1 1.2 1.3 Centre for Computing History, "Adman Grandstand TVG-2600 Mk II", CH22783 (retrieved 2026-10-18): "a Pong-style game console from 1977. It includes Tennis, Football, Squash and Target Shooting with the supplied Light gun. Two handheld controls are also included"; serial number 93097; the light gun is a "Thundercolt Super Marksman 304".
  2. ↑ 2.00 2.01 2.02 2.03 2.04 2.05 2.06 2.07 2.08 2.09 The two photographs on the Centre for Computing History record CH22783 (retrieved 2026-10-18), examined at the largest size offered. The console: a black panel with POWER (OFF/ON), BALL SERVE (MANUAL/AUTO), BALL SPEED, BALL ANGLE and PLAYER SIZE under AMATEUR and PROFESSIONAL, GAME SELECT switches A/C and B/D, the game key (TENNIS A-B, FOOTBALL A-D, SQUASH B-C, PRACTICE C-D, TARGET 1-B, TARGET 2-D), an orange RESET and a blue SERVE button, and LEFT PLAYER and RIGHT PLAYER sockets with two grey cylindrical hand controllers plugged in on grey leads; there is no COLOUR legend on the panel. The light gun: a black pistol whose body is held by screws on its side (three visible), with a threaded tip and a black cap on the barrel.
  3. ↑ Photographs by José Antonio Ortigueira Amor of the colour Grandstand TV Game 3600 Mk II, File:Adman Grandstand 3600 MK II Colour (2).jpg, File:Adman Grandstand 3600 MK II Colour (3).jpg, File:Adman Grandstand 3600 MK II Colour (13).jpg, File:Adman Grandstand 3600 MK II Colour (14).jpg and File:Adman Grandstand 3600 MK II Colour (15).jpg (CC BY 4.0, from Wikimedia Commons): the same panel layout and game key with a COLOUR legend and coloured dots added; the same grey hand controllers and Thundercolt gun with a twin plug; inside, a General Instrument AY-3-8500 on a board held to the upper case by two screws; the base label asks for six UM-2 cells or a 9 V 100 mA adaptor.
  4. ↑ 4.0 4.1 4.2 Wikipedia, "Grandstand (game manufacturer)", table of integrated Pong consoles (retrieved 2026-10-18): "Adman Grandstand T.V. Game 2600 Mk. II", black and white, six games (Tennis, Football, Squash, Practice, Target 1 and Target 2), made in Hong Kong, 1977 to 1979. The row cites the Centre for Computing History record, and its image link points to a South-West Retro Computing Archive item that is a TVG-3600 Mk II.
  5. ↑ 5.0 5.1 5.2 5.3 5.4 5.5 5.6 5.7 General Instrument Corporation, GIMINI TV Game Circuits, January 1978, pp. 4-7, PDF hosted by Pong-Story (retrieved 2026-10-18): AY-3-8500 data sheet; six games selected by grounding pins 18 to 23 (rifle 1, rifle 2, tennis, soccer, squash, practice); settings by grounding pins 5, 7, 8 and 13, with no more than 1 kΩ contact resistance; manual serve stops the game after each score; shot and hit inputs (pins 26 and 27) driven by positive pulses from the gun circuit; VCC +6 to +7 V, clock 2.012160 MHz ±1%, supply current 40 mA typical.
  6. ↑ 6.0 6.1 José Antonio Ortigueira Amor, "Adman Grandstand TV Game 3600 MK II Colour (1978)", Retro Ordenadores Orty (collector's blog, in Spanish), 23 November 2023 (retrieved 2026-10-18): on the 3600 Mk II the adaptor socket (9 V DC, centre positive) is on the left side and the light gun plugs into a jack and a mini-jack on the right side; the target games appear only when the gun is plugged in; four screws hold the lower case and two hold the board; the importer's 2600 series had six games.
  7. ↑ 7.0 7.1 7.2 David Winter, Pong-Story, "PONG in a Chip" (retrieved 2026-10-18): the AY-3-8500 plays four ball-and-paddle games and two target-shooting games with amateur and professional settings, and a seventh undocumented game, Handicap, when none is selected; Texas Instruments' TMS-1955 and TMS-1965 are pin-compatible with the AY-3-8500; the AY-3-8500 was used in "hundreds of different game systems".
  8. ↑ South-West Retro Computing Archive (University of Plymouth), item 262 (retrieved 2026-10-18): titled "Adman Grandstand TVG-3600 MKII"; its photographs show a boxed 3600 Mk II with a COLOUR legend on the panel and a "COLOR TV-GAME" base label.


Retrieved from "https://wiki.retrotechcollection.com/index.php?title=Grandstand_TV_Game_2600_Mk_II_Troubleshooting_Guide&oldid=26204"