I BOUGHT A PAC MAN MACHINE THAT THE MONITOR STOPPED WORKING ON. EVERYTHING ON THE MACHINE WORKS EXCEPT i CAN'T SEE ANYTHING ON THE TUBE. I WOULD LIKE TO FIX MY MACHINE

If this is a CRT type of arcade video game, it most likely uses an old-school flyback transformer, and a bunch of electrolytic capacitors. Check for cold or dry solder joints on all the boards (with the unit unplugged), and retouch any suspicious ones; especially the pins on the flyback, the CRT neck board/socket (if applicable) and in the power supply sections, where heat may be generated. Also check to see if the filaments light up in the CRT neck. It's also a good idea to check the caps in the power, horizontal and video sections as well - look for bulging or ruptured electrolytics, and/or burned resistors. Some arcade games (e.g. Asteroids) use a HV diode rated at around 25-30kV (it is located near the flyback and may have an insulated plug at each end). These can crack, short or simply go open circuit producing a "no display" symptom. If your game has this, check it before condemning the flyback or caps (the diode also doubles as a HV fuse). Do all the basic checks/visual inspections that you can thoroughly first before going any further with repair and/or restoration. It could be something really simple and easy to fix and/or obtain parts for (at reasonable cost if necessary).