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Tech and Marketplace => I need help with my game! - Technical Discussion => Topic started by: Gonk on November 15, 2015, 08:53:50 pm



Title: Zoo Keeper Video PCB Short
Post by: Gonk on November 15, 2015, 08:53:50 pm
I purchased a Power Supply from Arcade Shop with the Taito adapter. I hooked up all of the PCB's and when I power the PCB the LED's flash for a second but then shut off. The power supply also seems like it gets overlorded and the +5 only reads a half of a volt. When I disconnect the V1 connector then the power supply reads the correct voltage.

What is the best way to find the short? I am very nooby with PCB repair and any help would be greatly appreciated! Bill

If the V1 connector is unplugged then I don't have the short.
(http://i76.photobucket.com/albums/j38/wbfick/ZKPCB6_zpsftmafegu.jpg)

I did find some damage on the board (C85 and two IC chips), I have ordered new parts from Mouser.
(http://i76.photobucket.com/albums/j38/wbfick/ZKPCB5_zpsqranmrgd.jpg)




Title: Re: Zoo Keeper Video PCB Short
Post by: John's Arcade on November 15, 2015, 09:03:38 pm
Few random thoughts....


#1 - Unplug the coin door. Does that fix it?
#2 - Do you have the coin door bypass rom installed?
#3 - If #1 doesn't work see if you can isolate it to one of the PCBs by unplugging them and testing one at a time.


Title: Re: Zoo Keeper Video PCB Short
Post by: Gonk on November 15, 2015, 09:15:38 pm
Thanks for the reply

1. I don't have the coin door plugged in
2. I don't have a coin bypass ROM installed, I do have the coin PCB plugged in.
3. I believe the short is an issue in the video PCB, when I disconnect the V1 connector the power supply goes back to normal voltage.

Here is my test setup, I don't have the boards installed in the cabinet.

(http://i76.photobucket.com/albums/j38/wbfick/ZKPDBoverview_zps6byvnoe1.jpg)





Title: Re: Zoo Keeper Video PCB Short
Post by: iankellogg on November 16, 2015, 08:39:08 am
As john said, try to find out which pcb has the short. the fastest way to start would be to use your multimeter on resistance or continuity check and measure 5V to ground on each board unconnected with the rest.

The absolute best way is to try to burn the short and find it by either a thermal camera or by sensing the heat. but if you had the equipment to do that i don't think you would be asking this question ;)


Title: Re: Zoo Keeper Video PCB Short
Post by: John's Arcade on November 16, 2015, 10:12:17 am
I'd get that coin processor board out of there. Probably not the cause of your short but I would remove that variable:

http://arcarc.xmission.com/Arcade%20by%20Title/Zoo%20Keeper/Info_%20How%20to%20run%20Zookeeper%20without%20the%20coin%20processor%20board.txt