Flipper Nitro Ground Shaker

Nitro Ground Shaker (Bally, 1980): common faults and replacement boards (Bally MPU)

Does your Bally Nitro Ground Shaker fail to boot, have dead displays or runaway coils? These symptoms are typical of microprocessor Bally pinball machines, whose original MPU board is now over 40 years old and almost always suffers from a leaked battery. The good news: the BallyFA replacement MPU board, Plug & Play and battery-free, brings your machine back to life.

Nitro Ground Shaker (Bally, 1980): overview

Released in January 1980 on a drag-racing theme, Nitro Ground Shaker is a Bally solid-state pinball produced in around 7,950 units. It uses the Bally MPU of the AS-2518 series.

  • Manufacturer: Bally
  • Year: 1980
  • Electronic system: Bally MPU (AS-2518)
  • Type: solid-state pinball
  • Theme: drag racing
Bally MPU board (BallyFA) — Nitro Ground Shaker
The MPU board drives the whole Bally pinball.

Common faults (Bally / Stern)

On microprocessor Bally and Stern games (1977-1985), the recurring faults come from ageing: leaking battery on the MPU (corrosion of traces and sockets around U10/U11, the No. 1 cause of dead boards), tired 6821 PIAs (U10/U11) (oxidised legs, no boot), 5101 RAM and sockets to replace, MPU/power connectors oxidised or burnt (look for heat marks), displays with missing segments, and the power/driver board (rectifier, fuses, coil transistors) to rework.

Issues specific to Nitro Ground Shaker (forum feedback)

  • Leaked battery on the MPU: corrosion around U10/U11, to deal with first.
  • Dead or partial displays: display and MPU power to check.
  • Runaway or dead coils: driver board (transistors, fuses) to rework.
  • Oxidised or burnt connectors: to replace (repin) for a reliable machine.
  • Targets and mechanisms: outhole and target switches to clean.
  • Blowing fuses: a shorted rectifier or coil to track down.
Checking a Bally board with a multimeter — Nitro Ground Shaker
The multimeter: essential to check the power supply and diagnose the MPU.

Replacement boards compatible with Nitro Ground Shaker

BallyDri power and driver board for Bally — Nitro Ground Shaker
The BallyDri: replacement power and driver board, Plug & Play installation.

📚 Further reading: Guide: which MPU board for a Bally / Stern (1977-1985)?

The BallyFA replaces the original MPU board (boot-up, logic, battery-free memory) and removes the battery, the No. 1 cause of corrosion. For the coils and power, the BallyDri takes over; the lamps via the BallyLa_60. Plug & Play installation, battery-free, free support. Contact us.

FAQ — Nitro Ground Shaker Bally

My Nitro Ground Shaker won't boot.
Check the battery and corrosion around U10/U11. The BallyFA replaces the MPU and works without a battery.

Some coils run away or don't respond.
On the power side, the driver board is to blame: the BallyDri (power + driver) replaces it.

Is the BallyFA compatible with my Bally?
Yes, for microprocessor Bally/Stern games (1977-1985). If in doubt, contact us.

Should I keep the original battery?
No. The BallyFA works without a battery and removes the No. 1 cause of corrosion.

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

  1. Powered off, visual inspection: look for any battery or corrosion trace on your Nitro Ground Shaker's MPU, especially around U10/U11; remove the battery if it is still present.
  2. Power supply: measure the 5 V and check it reaches the MPU (rework the power/rectifier board and fuses if the voltage drops).
  3. Grounds and connectors: rework the oxidised or burnt MPU/power connectors (heat marks) between the boards.
  4. MPU components: check the 6821 PIAs (U10/U11) and the 5101 RAM, often tired or corroded by the battery.
  5. Displays: never plug or unplug a display while powered on; test with a known-good display.
  6. Final test: check boot-up, credits, coils and displays; reminder: the BallyFA replaces the MPU and boots without a battery. If needed, contact our free support.

See also

Sources & further reading

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