Paragon (Bally, 1979) : pannes et cartes de remplacement (MPU Bally)
Does your Bally Paragon no longer start, have its displays off or runaway coils? These symptoms are typical of Bally microprocessor pinball machines, whose original MPU board is now over 40 years old and almost always suffers from a battery that has leaked. Good news: the BallyFA replacement MPU board, Plug & Play and battery-free, brings your machine back to life.
Paragon (Bally, 1979): overview
Released in 1979 on an heroic fantasy theme (barbarian and creatures), Paragon is a large Bally widebody pinball with superb artwork, considered one of the most beautiful ever produced. It uses the Bally MPU from the AS-2518 series.
- Manufacturer: Bally
- Year: 1979
- Electronic system: Bally MPU (AS-2518)
- Type: electronic pinball (solid state), widebody
- Theme: heroic fantasy / barbarian
Common faults (Bally / Stern)
On Bally and Stern microprocessor machines (1977-1985), 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, impossible start-up), 5101 RAM and sockets to replace, MPU/power connectors oxidised or burnt (look for heat marks), displays with missing segments, and a power/driver board (rectifier, fuses, coil transistors) to rework.
Issues specific to Paragon (forum feedback)
- Leaked battery on the MPU: corrosion around U10/U11, to deal with first.
- Very busy widebody playfield: many coils and lamps; harnesses and connectors to watch.
- Displays off or partial: the displays' power supply and MPU to check.
- Runaway or dead coils: driver board (transistors, fuses) to rework.
- Oxidised or burnt connectors: to replace (repin) to make the machine reliable.
- Blowing fuses: look for a shorted rectifier or coil.
Replacement boards compatible with Paragon
- BallyFA — replacement MPU board (battery-free).
- BallyDri — power supply + driver.
- BallyLa_60 — lamp driver.
📚 Further reading: Guide: which MPU board for a Bally / Stern (1977-1985)?
The BallyFA replaces the original MPU board (start-up, logic, battery-free memory) and does away with the battery, the no.1 cause of corrosion. For the coils and the power supply, the BallyDri takes over; the lamps via the BallyLa_60. Plug & Play installation, battery-free, free support. Contact us.
FAQ — Paragon Bally
My Paragon no longer starts.
Check the battery and the corrosion around U10/U11. The BallyFA replaces the MPU and works without a battery.
Coils run away or don't respond.
On the power side, the driver board is at fault: the BallyDri (power supply + driver) replaces it.
Is the BallyFA compatible with my Bally?
Yes, for Bally/Stern microprocessor machines (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
- Power off, visual inspection: look for any battery or corrosion trace on the MPU board of your Paragon; remove the original battery if it is still present.
- Power supply: measure the voltages (especially 5 V) and check they reach the MPU; check the rectifier and the fuses on the power board.
- MPU components: check the 6821 PIAs (U10/U11) and the 5101 RAM, often oxidised by the battery.
- Connectors: repin the oxidised or burnt connectors, especially between the MPU and the power supply.
- Displays: check the displays' power supply; test with a known-good display.
- Final test: check start-up, credits, coils and displays; the BallyFA replaces the MPU without a battery; if needed, contact free support.
