|Jungle Lord / Williams 7 Driver Board Update #3
|Posted by: AceBHound on Sep 9th, 2010 8:59 PM
|Got the 74F02 Quad 2-Input NOR Gate ICs today -- to replace the IC8 (used for Special Solenoids on the Williams Driver Board). I tried plugging the board in yesterday without IC8 in the board since I was still waiting on receiving the parts -- and it blew the solenoid fuse again. Today when testing on the bench I noticed with the new 74F02 chip in (see blue circle in picture) I received led pulses correctly now on connector 2J12 (Special Solenoids Drive) on the driver board, whereas with the bad IC some of the 2J12 pins were showing locked on solenoids. I then decided to remove IC8 chip again and sure enough the pins were locked on. So it seems with the way the blanking signal is between the CPU board and driver board and components on the driver board, just removing a component like the 7402 doesn't mean the coils won't lock on. In fact, instead of only a few coils locking on it locked all the coils that IC8 would normally control. So now I have one working driver board!
I also noticed the low audio was due to non-amplified audio since the soundboard connector for the volume knob potentiometer was upside down. I didn't do that -- but definitely teaches you to always attack problems from the simplest thing first since it's easiest to isolate and will save you loads of frustration when you figure out you didn't have to tear into a board with a soldering iron. I replaced a flipper spring, adjusted the flippers some and replaced a few light bulbs and played a few games. Still have more work to do, but great to finally get one driver board working and be able to play a game! Getting closer to taking on the King of the Jungle!
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