Dracula (Stern, 1979): faults and replacement board (Stern M-100 MPU)
Is your Stern Dracula refusing to start, showing dead displays, leaving drop targets that will not fall or firing runaway coils? These symptoms are typical of Stern microprocessor pinballs (M-100 MPU): the original board is over 45 years old and almost always suffers from a leaking battery. A battery-free replacement board gives the machine a second life.
About the Dracula (Stern, 1979)
Released in January 1979, Dracula is a solid-state pinball from Stern Electronics designed by Harry Williams, with roughly 3,612 units produced. The playfield offers three flippers, three active bumpers, one passive bumper, a spinner, a horseshoe lane and seven drop targets shaped like gravestones. It uses the Stern M-100 MPU board.
- Manufacturer: Stern Electronics
- Year: 1979
- Electronic system: Stern M-100 MPU
- Type: solid-state pinball
- Theme: horror / vampires
Common faults (Stern M-100)
On Stern M-100 machines (1977-1979), the recurring faults all come from ageing: a battery leaking on the MPU (corroded traces around U10/U11, the number-one cause of dead boards), tired logic circuits (5101 RAM, 6821 PIA, no boot possible), oxidised or burnt Molex connectors between the MPU and the power supply, displays with missing segments, and the power/driver board to overhaul (bridge rectifier, fuses, coil transistors).
Dracula-specific issues (from forums)
- Reproduction “gravestone” drop targets that are too soft: current repros twist by around 45° against half that on the original targets, which leaves balls rattling around on the bank.
- Seven-target drop bank that will not reset: check the reset coil, a seized mechanism or the corresponding driver transistor.
- Three flippers to maintain: the extra flipper adds another set of EOS contacts and coils to check when diagnosing.
- Spinner and horseshoe lane: dirty or misadjusted contacts, a source of erratic scoring or no scoring at all.
- Battery leaked on the MPU: deal with this first — the corrosion attacks the traces under the U10/U11 sockets.
- Oxidised Molex connectors in the backbox: re-pin them to make starting and the displays reliable.
Replacement boards compatible with the Dracula
Important: the Dracula uses a Stern M-100 MPU, close to but distinct from the Bally boards. Confirm the right board before ordering: contact us with the references of your boards.
- BallyFA — battery-free MPU.
- BallyDri — power supply + driver.
- BallyLa_60 — lamp driver.
Plug & Play installation, battery-free, free support.
FAQ — Dracula Stern
Which replacement board for my Dracula?
The Dracula is fitted with a Stern M-100 MPU: contact us with the references of your boards and we will confirm the right solution (battery-free).
My drop targets do not drop cleanly.
Reproduction targets are softer than the originals and twist more. Choose repros as close as possible to the original Stern targets.
My drop target bank will not reset.
Check the reset coil, then that the mechanism moves freely, then the corresponding driver transistor.
Should I keep the original battery?
No: a battery-free board removes the number-one cause of corrosion.
Does a battery-free board keep the settings and high scores?
Yes: non-volatile memory keeps settings and scores when the machine is switched off, with no battery and no corrosion.
What is the warranty?
6-month warranty (parts and labour) against any fault not caused by misuse, plus 30 days money-back. Free technical support.
See also
Sources
Is your machine down right now?
Tell us your machine and the exact symptom — we'll tell you which board you need, or whether you need one at all. It's free, and Valère answers personally.
Describe my fault →Not ready to order yet?
Get our troubleshooting guides, restoration tips and new product news — about one email a month, never spam.
