Excalibur (Gottlieb, 1988): Faults and System 80B Replacement Boards

Q: Is a wiring extension needed for the board on 80B?

Often yes: on the Excalibur, the display ribbon cable can be a little short and the backbox neon/fluorescent tube sometimes has to be raised to clear the GottFA80 Light. Our tutorials and free support guide you.

June 25, 2026

Does your Gottlieb Excalibur have faulty drop targets, sound that cuts out, blank displays or does it reset? These symptoms are typical of Gottlieb System 80B pinball machines, whose original boards (MPU, Driver, power supply, sound) are now over 40 years old. The good news: modern replacement boards, Plug & Play and battery-free, give your machine a second life.

Excalibur (Gottlieb, 1988): overview

Released in 1988, Excalibur is a large-format System 80B pinball machine with a medieval theme, set in the world of King Arthur and the legend of the sword. It features the series' alphanumeric displays.

Manufacturer: D. Gottlieb & Co.
Year: 1988
Electronic system: Gottlieb System 80B
Type: solid state electronic pinball, large format
Theme: medieval / King Arthur

Gottlieb System 80B boards — Excalibur — The CPU and Driver boards of the Gottlieb System 80B.

Common faults (System 80B)

The System 80B uses alphanumeric displays and an MPU with battery-backed RAM 5101. Recurring faults: leaking battery on the MPU (corrosion and loss of the 5101 memory), unstable power supply (the original trim pot struggles to hold the 5 V and 12 V), cracked solder joints (especially on the CPU daughter card), inter-board connectors needing repinning, deficient grounds (ground mods essential), dead displays if a single bit does not pass from the MPU to the display, and start-up disrupted by the starter of the fluorescent tube in the backbox.

Issues specific to the Excalibur (forum feedback)

Drop target bank: the bank's bare common wire can break while still appearing connected.
Sound that cuts out: the Gottlieb pins between the sound board and MPU lose their voltage; repin the sound board and auxiliary power supply.
Sound diagnosis: press firmly on the sound board chips, with the game powered on, to spot a bad contact.
Blank displays / grounds: properly connecting the grounds to the transformer often restores the display.
Transistors and edge connectors: tighten the transistors and clean the dirty edge connectors.

Battery corrosion on a Gottlieb System 80B board — Excalibur — Typical corrosion from a leaking battery on System 80B: address it first.

Replacement boards compatible with Excalibur

GottFA80_Plus (Light) — all-in-one board CPU + Driver + power supply, without sound.
GottFA80_Plus (Full) — same with integrated sound board (80B audio limited to a few titles).
Gosof — replacement sound board for System 80 and 80A (80B support currently limited to a few titles).
Godri80 — replacement Driver board.
Lisy80 — CPU board + web diagnostics.
GoPOP80 — bumper driver board (MA-922).

GottFA80_Plus board for Gottlieb System 80B — Excalibur — The GottFA80_Plus: all-in-one board (CPU + Driver + power supply), battery-free.

System 80B specifics: favour the GottFA80_Plus Light — the 80B is covered on the CPU/MPU side. On the audio side, support is for now limited to a few titles (Bounty Hunter, Chicago Cubs Triple Play, Tag Team); for the other System 80B machines, keep and repair the original sound board and contact us (an audio solution is in preparation).

To plan for when fitting on 80B: in full transparency, on a System 80B like the Excalibur, the original display ribbon cable is sometimes a little short to reach the GottFA80 Light in its new position: a small display wiring extension may be needed. You also often need to raise or slightly reposition the neon/fluorescent tube of the backbox to clear the board. Nothing complicated: we provide the advice and support free of charge.

Plug & Play installation, battery-free, tutorials and free support. Contact us.

FAQ — Excalibur Gottlieb

A target bank no longer responds.
Check the bare common wire, which may have broken. Then check the switches; a new MPU makes the reading more reliable.

The sound cuts out.
Repin the sound board and auxiliary power supply and repair the original sound board. For 80B audio, support is limited to a few titles — contact us.

My displays are blank.
Correctly connect the grounds to the transformer and reseat the ribbon cable. A replacement MPU makes the display interface more reliable.

Is a wiring extension needed for the board on 80B?
Often, yes: on the Excalibur, the display ribbon cable can be a little short and the backbox neon/fluorescent tube sometimes has to be raised to clear the GottFA80 Light. Our tutorials and free support guide you.

And what about 80B sound?
Audio support is for now limited to a few titles (Bounty Hunter, Chicago Cubs Triple Play, Tag Team). For Excalibur, keep and repair the original sound board and contact us; a solution is in preparation.

How long does it take to install a replacement board?
Installation is Plug & Play: a few minutes, no soldering, with tutorials and free support.

Does a battery-free board keep the settings and high scores?
Yes. Modern replacement boards use non-volatile memory: no more battery, no more corrosion, and the settings are kept when powered off.

Step-by-step diagnosis

Power off, visual inspection: look for any battery or corrosion traces on the MPU of your Excalibur; remove the NiCad battery if still present.
Power supply: measure the 5 V and check that it reaches the MPU (resolder the regulator or Q1 if the voltage drops).
Grounds: apply the « ground mods » between the boards (CPU, Driver, power supply, sound).
Connectors: re-pin the oxidised Molex connectors, especially the MPU↔Driver link.
Displays: never plug or unplug a display while powered on; test with a known-good display.
Final test: check start-up, credits, coils and displays; if needed, contact free support.