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    😱 Repair log: Elvira's House of Horrors (Stern, 2019)

    2019 Elvira's House of Horrors Repair log Stern

    Repair logs are quick summaries of workshop and on-site repairs. If your machine needs a service, πŸ“¬ Contact Us to discuss how we can help!


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    Let's fix this Elvira LE. This one wasn't booting up. Power switch was on but there were no lights on the playfield, no display, nothing! All fuses were OK and voltages were all present as well. To this end, the diagnostic LEDs on the CPU board are handy for determining whether it's a voltage problem or a CPU problem. LEDs were all lit except for VMA and VMB. A typical sign that the CPU just isn't booting up.


    Spike system games are notorious for problems with the game code on the SD card so this should always be the first stop. The card slot breaks, the card unseats itself, or the data on it becomes corrupted. Quickest route for troubleshooting is to replace the SD card and flash it with new game code. Stern's website has instructions on how to do so. Once the new card was in the game, it booted right up. The old card now lives in the bin!


    After some playtesting another issue revealed itself. The up-kicker in the cellar would often fire multiple times even when there was no ball in there. The opto switch appeared to work OK, but I know better than to trust a Stern opto board. The receiver side seemed OK and tested fine with an external light. So it was the transmitting side that was the issue. The transmitter board is under the mansion plastic, and can be adjusted without removing too much hardware as there's a hole in the metal bracket which you can use to loosen the board. Just remove the turret plastic (1 screw) and the main mansion plastic (2 screws). I did this and repositioned the transmitter board slightly so it would align better with the receiver opto. No more issues after that! 


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    🦍 Repair log: King Kong LE (Stern, 2025)

    2025 King Kong Repair log Stern

    Repair logs are quick summaries of workshop and on-site repairs. If your machine needs a service, πŸ“¬ Contact Us to discuss how we can help!


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    Quick service call on a King Kong LE today. Owner had just bought the machine from someone and wanted it to have a quick check-over, as well as some mods installed. Nothing to report after the check-over, as all switches, lamps, coils and motors were working just fine. As I would hope for a one-year-old machine! 


    Helped install a couple of mods including a custom shooter rod and topper. The topper looks great but note that there is a lot of additional work involved in installing it other than mounting it to the top of the cabinet. It comes with a set of plastic characters which you have to punch out of a template and slide into the marquee to create your own message. Each character is on a different piece of plastic, and each plastic has a front and rear backing which you have to peel off before installing. The same applies to the chain links and handcuffs for Kong. Each one of those tiny chain links has backing on both sides which you have to punch out of the template, peel, and connect together. Bring a small blade or a long fingernail; you're going to need it!


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    πŸ€– Repair log: Transformers Limited Edition (Stern, 2011)

    2011 Repair log Stern Transformers

    Repair logs are quick summaries of workshop and on-site repairs. If your machine needs a service, πŸ“¬ Contact Us to discuss how we can help!


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    Minor service on a Transformers (Combo LE). A very popular theme but with only 500 of these LEs made, you don't see them very much!


    Slingshot rubbers were gone so they were replaced first up. Left slingshot was still not firing. Coil was working OK in test mode but the switch wasn't registering at all, so time to look at the assembly under the playfield. A broken diode on the switch was the cause.


    Next: ball hang-ups in Megatron. This is a common problem that was partially solved by code updates. Sometimes, a ball shot into the trough under Megatron won't be recognised. This trough is an odd design with only one entry and exit point, yet it must also be able to stack multiple balls for multiball. The fix here was to increase the pitch of the game a little so gravity helps the balls fall into line a little better. You can also put washers under the assembly to give it some more angle. In most cases the software should compensate by firing the trough coil weakly to "dislodge" any stuck balls. An odd mechanism design!


    The captive ball has a toy Bumblebee car in it instead of the captive ball. However the car was getting stuck halfway up the lane and would not roll down nicely. The main cause of this appeared to be the design of the car. The base has a Bumblebee design embossed into it, which creates ridges that bind on the switch actuator in this lane. Some tape over the base of the car helped smooth it out somewhat, but replacing it with a different car would be the best approach. Unfortunately I don't carry extra Bumblebees in my toolbox!


    Balls were occasionally getting stuck on the top of the left ramp. This is a poor ramp design with a huge lip on the metal ramp that doesn't quite fit into the "slot" on the plastics it joins with. I couldn't create any more space here so some Mylar over the lip was the best solution.


    Of course this is only the first Transformers machine made by Stern. They've just released another one (More than Meets the Eye). Hopefully it will be a while until I have to feature one of those on this blog!


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    Repair log: Playboy (Stern, 2002)

    2002 Playboy Repair log Stern

    ο»ΏRepair logs are quick summaries of workshop and on-site repairs. If your machine needs a service, πŸ“¬ Contact Us to discuss how we can help!

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    Service call to a Stern Playboy a couple of days ago. I took the MPU board in for repair to abate some alkaline corrosion from leaking batteries. Replaced with a lithium cell and installed NVRAM while I was there.


    Little bit of work to do on the playfield, too. The triangle motor wasn't stopping at the correct spots for "Splash" and "Triple Jackpot" awards. The switches underneath the assembly were out of adjustment. The clear plastic above the left ramp was missing. This resulted in shots to the ramp getting rejected most of the time. I fashioned a new plastic out of polycarbonate, drilled the mounting holes, and voila! Not as precise as a CNC cut plastic, sure, but not bad for an on-site repair either! Also installed a custom topper and wired it into the backbox. Changed a few rubbers and replaced a couple of switches to finish things off.


    Welcome back to the mansion!


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    Repair log: Batman: The Dark Knight (Stern, 2008)

    2008 Batman Repair log Stern

    ο»ΏRepair logs are quick summaries of workshop and on-site repairs. If your machine needs a service, πŸ“¬ Contact Us to discuss how we can help!

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    New shaker motor installed! An awesome addition to the game which really makes you feel those shots to the crane.


    Some of the early SAM system games were made with a shaker motor option available, but the cabinets were not always prepared for installation of the assembly at the factory. As a result, you may need to drill the mounting holes and install tee-nuts so you can bolt the shaker motor into place. Ensure proper alignment and fitment as this is not a mechanism that you want to shake loose!


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    Repair log: Stern Stars (1978) and Stern Dracula (1979)

    1978 Dracula Repair log Stars Stern

    ο»ΏRepair logs are quick summaries of workshop and on-site repairs. If your machine needs a service, πŸ“¬ Contact Us to discuss how we can help!

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    A couple of Stern MPU-100 boards came in for service. Both with similar corrosion damage which required significant abatement. Once the corrosion was dealt with, the boards were repopulated.


    A couple of small mods were done, too. Batteries and RAM were replaced with NVRAM modules from Tangles Pin Parts. A nice product from an Aussie supplier. One of the ROM chips was damaged on the Stars board, so I combined the two 2716 ROM images into a single 2764. Some modding of the board was required to accommodate the 2764 but it works well.


    Before and after photos of one of the boards below!