Field guide
Hidden Software Switch (Ron Harris)
How it works
A highly technical cheat where an insider or technician replaces the machine’s EPROM or software chip with a modified version containing hidden backdoors or altered payout logic. The perpetrator accesses the machine’s logic board and swaps the original chip for a doctored one. The modified chip may contain a hidden software switch triggered by a specific sequence of coins bet that guarantees a jackpot or overrides the RNG.
On the record
In the early 1990s, Nevada Gaming Control Board employee Ron Harris altered the Board test program so that it inserted a cheating routine into chips on machines under inspection and he told accomplices how to trigger jackpots. A later CNN account said he retooled more than 30 machines. The 1996 Nevada indictment, as reported by the Las Vegas Sun, charged about $32,000 in slot cheating. A 2006 CNN account said the take was hundreds of thousands of dollars.
Detection & preventionADVISORY
The paid halfHow a monitoring room catches hidden software switch (ron harris), and what stops it recurring, written for the desk, not the reader.
Detection and prevention is the paid layer. It opens on all 400 methods with the downloadable edition, or with any paid plan.
Every subscription tier carries full access to the Cheats & Scams Library, Professional upward: the detection and prevention notes on all 400 methods, plus the searchable edition as a download.
Already subscribed? Sign in and this opens.
Sources
- Nevada Gaming Control Board — Excluded Persons: Ronald Dale HarrisRegulator document
Sources last checked 2026-08-14
Published as a detection reference for surveillance, compliance and gaming-operations professionals. Thresholds and tuning are set by the property. Nothing here is instruction: the method is described so it can be recognised.