Gold Fishin' uses inferred optics to create a "net" over the top of the playfield to prevent people from cheating the game. There are two transmitters that are mounted in blue housings on the rear graphic and three receivers located behind the foul line plexi which are controlled by the MJ2040X controller board, when the inferred beams are broken it sends a signal to the main board to tell it to activate the cheat routine. When a customer reaches in the game and triggers a cheat on the game it will turn all of the playfield bowls red and award the lowest amount of tickets on the score chart, the duration that the sensor input needs to be blocked is adjustable at programming option 19.
Checking transmitters: MJ2039TX
The transmitters located at the back of the game are 5VDC devices. They are pulsed off and on by the
cheat sensor board. On the sensor’s 2 pin connector you will see +5vdc with minor fluctuations. You
can also use an IR detector or low res digital camera to see that the transmitter LEDS are on and
operational. You can check the connections for the transmitters to J4 on the cheat sensor board.
Checking receivers: MJ2039RX and MJ2039RGFX
Each receiver board has a 3 pin connector. Pin 1 is 12vdc power, pin 2 is DC ground, and pin 3 is the
cheat signal line. The sensor signal for the left and right receivers will be +2.5vdc when inactive and go
to +5vdc when the receiver is blocked. The center sensor will have at pin 3 0vdc when inactive and go to
+5vdc when blocked. You can check these signals on the J2 connector on the cheat main board.
Cheat sensor board: MJ2040X
The cheat sensor board interprets the incoming signals and then outputs all three signal as one to the
main board. The connector at J1 is the input power, you should have +12vdc between the orange and
black wire. The signal line from the cheat board to the main board is located on connector J4 pin 2, you
should see 0vdc when the receivers are inactive and +5vdc when the receivers are blocked. The signal
from the cheat sensor board connects to the main board at connector J27 pin 3. The cheat main board
has a LED indicator at location D1. Normal operation for the led is constantly flashing.