Changing the EPROM chip

Introduction
These instructions explain how to change the EPROM chip.
You must remove/install the ROM chip properly, otherwise the game will not boot up, and possible damage may occur to the EPROM chip, and/or the game's circuit boards

Preparation
You will need a small flathead screwdriver to pry up the EPROM chip from its socket. Take precaution against electrostatic shock to the circuit board and EPROM chip(s) by grounding yourself before handling them.

Step 1: Remove the old EPROM Turn the Pinball power off! Always remove and replace chips ONLY WITH POWER OFF, AND THE PIN UNPLUGGED. Locate the old EPROM on the circuit board. The replacement EPROM MUST be installed with the same orientation as the original, or it will not work properly. NOTE the end of the chip that has the notch on it. The notch is also painted in white outline on the circuit board to ensure proper orientation. Insert the tip of a small flathead screwdriver in the spacing between the PROM and its socket. Avoid making any contact with the other components on the board. Make sure that you don't insert the removal tool between the socket and the PC board, this will pry the socket and the chip off the board and will damage the board! Pry the chip upward gently as you insert the screwdriver, keeping the EPROM level as it is raised from the socket. If the screwdriver is too wide, such that fully inserting it between the EPROM and the socket would make contact with the pins, insert the screwdriver only partially and pry up one end of the chip slightly, then pry up the other end of the EPROM. Repeat this process, keeping the chip level as it is raised. If you are replacing the old EPROM with a firmware update, place the old EPROM on the anti-static foam block beside the new EPROM, for storage. Avoid damaging the old EPROM so that it can be used again, if necessary.

Step 2: Install the new EPROM Grasp the new EPROM by its ends (try not to touch the pins) and remove it from its foam holder. Note that the notch on top of the chip should point toward the notch drawn on the silk screen of the circuit board or the chip socket. The pins of the chip are preloaded (spread wider than the separation between the rows of pinholes) to assure that they will make good contact when the chip is seated. Thus, you cannot insert the EPROM if it is level with the socket. Tilt the EPROM sideways and place one row of pins into one side of the socket so that the pins are resting at the top of their respective pinholes, then tilt the EPROM toward the socket until the other row of pins makes contact with the top of the holes. The tops of the holes are angled so that the pins will be guided inward as gentle pressure is applied. However, before applying pressure make sure that all the pins are indeed aligned, and that they are not hanging over the edges of the socket. If the pins are spread too wide, prod each pin gently into place with the screwdriver as you press the EPROM into the socket. Note that when the EPROM is fully inserted, a tiny gap will remain between the bottom of the EPROM and the socket. You assume full responsibility for any damage that may be caused to your chip or game.