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Tech and Marketplace => I need help with my game! - Technical Discussion => Topic started by: Mike Rofarad on July 20, 2017, 07:06:36 pm



Title: Need Help Identifying Part - Arachnid Super 6 Plus II Arcade Style Dart Board
Post by: Mike Rofarad on July 20, 2017, 07:06:36 pm
Hi everyone. I just picked one of these up the other day for a good deal. The previous owner stated that the game worked, but that it would start smoking soon after it was turned on. I had him fire it up for a few minutes and sure enough, the unit started smoking near the CRT monitor. We opened the access panel and I noticed it was coming from the board controlling the monitor. I figured it was something I could repair since I am a bit handy with electronics work. Anyway, after I got it home I removed the monitor and controller board to determine exactly what was blown. It was a blown resistor running part of the focus circuitry for the monitor. Not only that, but since this was a double-sided circuit board, part of the board below the resistor was scorched as well and actually glowed a bit when I reapplied power. Apparently the high voltage generated from the nearby flyback transformer was arcing between the circuit traces on both sides of the board. Below is a pic of the board showing the space where I have already removed the burnt resistor and the hole in the board where the damage occurred:
(http://i65.tinypic.com/35a192s.jpg)

I found the schematic for the Omnivision monitor circuit that matches mine. The blown resistor is labeled as R78 and is shown to have a value of 1 ohm, which I know has to be a typo. I don't really want to guess on the correct value since this part of the circuitry is on the 600v output of the flyback. Is there anyone out there who has one of these games and can open the access panel and tell me what the value or band colors are on this particular resistor? The correct resistor would be on the very left hand side of the monitor control board (right behind the CRT monitor after the panel is opened), sandwiched right between the small disc capacitor near the flyback and the small diode near the edge of the board. Any help would be greatly appreciated!