Dragon (Gottlieb, 1978): Troubleshooting and System 1 Replacement Boards
Your Dragon by Gottlieb has phantom credits, a corrupted credit counter, stuck continuous sound, or insufficient 5V? These symptoms are typical of Gottlieb System 1 pinball machines whose original boards are now over 40 years old. The good news: our battery-free replacement boards, Plug & Play, bring your machine back to life.
Dragon (Gottlieb, 1978): Overview
Released in 1978, Dragon is a System 1 machine with a heroic-fantasy dragon theme and alphanumeric displays. It uses the Gottlieb System 1 electronics.
- Manufacturer: Gottlieb
- Year: 1978
- Electronic system: Gottlieb System 1
- Type: solid state
- Theme: medieval-fantasy / dragon
Common Issues (System 1)
The Gottlieb System 1 shares a well-known set of weaknesses regardless of the game:
- Leaking battery: the NiCad battery soldered to the MPU board corrodes traces and components over time. This is the #1 failure — remove it immediately.
- Poor grounds: the original ground wiring is undersized and causes resets and erratic behavior (ground mods are virtually mandatory).
- Corroded connectors: Molex connectors, especially the 46-pin MPU-to-driver connection, lose contact and require re-pinning.
- Power supply: unstable 5V (often the legs of transistor Q1 or the R4 trim pot), tired rectifier bridges, and overheating transformers cause crashes.
- Displays: digits that fade, flicker, or freeze at zero. Never connect or disconnect a display while powered on.
Dragon-Specific Issues (Forum Reports)
- Phantom credits: you insert 4 credits, start the game, and the 3 remaining credits vanish; the counter can also freeze on an impossible value (over 15).
- Corrupted credit counter: after a loss of power to the CMOS RAM, the credit display no longer matches reality and simply clearing the audits isn't enough.
- Stuck sound: a single continuous tone comes from the speaker, sometimes even after replacing the sound board — investigate power supply and connections.
- Insufficient 5V: check that the power supply delivers a proper 5V and that it reaches the MPU; below 5V the behavior becomes erratic.
- Missing protections: add the recommended fuses and check the protection diodes, often absent or worn.
Compatible Replacement Boards for Dragon
Dragon runs on the Gottlieb System 1, a platform known for its fragility (leaking battery, weak grounds, corroded connectors). Pinballs Store offers battery-free replacement solutions:
- Gosof — replacement sound board.
For a dedicated System 1 CPU/driver board, contact us: we'll point you to the best solution for your Dragon. Plug & Play installation, battery-free, with free support.
FAQ — Dragon Gottlieb
My credits vanish or the counter freezes.
A CMOS RAM power-loss issue (battery). Remove and replace the failing battery memory; a modern battery-free CPU with NVRAM eliminates it — contact us.
I get one continuous stuck tone.
Investigate the sound board power supply and connections — it can persist even after a board swap. The Gosof replacement sound board is a battery-free option.
Do you have a replacement CPU board for my System 1?
Contact us — we'll point you to the best battery-free solution for your machine. The Gosof already covers the sound board.
Do I need to keep the original battery?
No. The NiCad battery is the #1 cause of corrosion on System 1 — remove it. Modern replacements are battery-free.
How long does installation take?
Our replacement boards are Plug & Play: just a few minutes, no soldering required, with tutorials and free support.
Does a battery-free board retain settings and high scores?
Yes. Modern replacement boards use NVRAM: no battery, no corrosion, and settings are preserved when powered off.
Step-by-Step Diagnostics
- With power off, visual inspection: look for battery leakage or corrosion on the MPU of your Dragon; remove the NiCad battery immediately if still present.
- Power supply: measure the 5V rail; if low, re-solder the legs of transistor Q1 and check the R4 trim pot.
- Grounds: apply the System 1 ground mods (ground wires to the CPU and driver boards).
- Connectors: re-pin the oxidized 46-pin MPU-to-driver Molex connector and the connectors under the battery.
- Displays: never connect or disconnect a display while powered on (it can destroy the display driver chips); test with a known good display.
- Final test: verify startup, credits, solenoids, and displays; if needed, contact free support.
Useful Guides
- How much does pinball machine repair cost? A price guide
- How much is my pinball machine worth? Value and estimation
- Pinball machine leg sizes: the complete guide
- Which board for a Gottlieb System 80, 80A or 80B?
See Also
- Joker Poker (Gottlieb, 1978)
- Count-Down (Gottlieb, 1979)
- Solar Ride (Gottlieb, 1979)
- Torch (Gottlieb, 1980)
