Play Meter

TECHNICAL TOPICS By Douglas Douglas McCallum McCallum By Clearing away Cl earing a way monitor problems problems monitor By far the vast majority of our Wefind findourselves ourselveswith withmore moreand and We By far the majority Motorola of our monitors are vast Motorola's. more video equipment these days, more video equipment these days, monitors are Motorola's. Motorola makes a really good product in my and, in many spots, the arcades and, in many arcades a really goodare product in my estimation . There basically two especially, thesespots, gamesthe are the main makes especially, these games are the main estimation. There are basically types in use: the older type withtwo the source of revenue (Space Invaders, source (Space in use: older XM501/701), type with the plug-in PCB the (models geez!!).ofSorevenue now more thanInvaders, ever, it's types XM501/701), (models geez!). So to now more than ever,up it's. plug-in important keep these games and thePCB newer type with most of the with most of the . type (XM5000/7000) theonnewer important to keep these gamesThey're up. and Let's look at monitors. parts the PCB Let's look at monitors. They're on numbers the PCB starting (XM5000/7000). Model with five five fairly reliable and most failures can be parts numbers starting with fairly reliable mostcategories. failures can be Model have 19-inch screens and those with lumped intoand certain have 19-inch screens and those with lumped into certain categories. VIDEO IN - HORIZ OUT II f O FLYBACK VERT SIŻE IN VERT LIN 5 +/30 v +130 11'/V +100V REG. CONTRAST BRIGHT VERT HORIZ HOLD HOLD TEC Monitor TEC Monitor haveaa23-inch 23-inchscreen. screen . 77have an increasing We are also seeing We areofalso seeing by an TEC, increasing espenumber monitors number of monitors by TEC, especially in Atari products. Occasionally cially Atari you in may runproducts. into one Occasionally of Midway's of Midway's into one may run jobs. you homemade Recently a new homemade jobs. Recentlyhasa shown new monitor by Wells-Gardner monitor haswith shown up and by it'sWells-Gardner almost identical the with the identical it's almostbut andMotorola, up older not enough so's older Motorola, but not enough so's we can swap PCB's. can swap PCB's. we Monitors workthe thesame sameso sowe'll we'll Monitors allallwork go over some general procedures go general procedures andover thensome look for for convenient test and then look test points. The industryconvenient has done us a points. The industry has donethe us 12 a big favor ; they standardized 12 theswap standardized big pinfavor; input they connector so we can pin input connector so we can swap monitors around at will, so long as monitors around will, sosize. long The as they're the sameat screen they're the same screen size. The only exception to this is the occasion only exception to this is the occasion where the game requires a 5-volt where the game requires a 5-volt supply-not all monitors have them supply-not all monitors (nor do audio systems,have butthem that (nor do comes audio up systems, butoften). that situation much less situation up much lessproblems often) . Let's comes approach monitor Let's approach monitor problems symptomatically, in a trouble shootsymptomatically, in a trouble shooting guide ... ing guide ... Raster, but no picture: Raster, but noevidence picture: of game logic Is there 1.1. Is there evidence game problogic (sounds, etc .)? If not,ofthere's (sounds, etc.)? If not,generated there's probably no picture being ; find ably picture being generated; find out no why. out why. 2 . Do the "Pin 1" test-turn up the 2.brightness Do the "Pin test-turn up way, the and 1" contrast all the brightness all and the way, disconnectand the contrast logic PCB, touch disconnect theinput logic PCB, and touch pin 1 of the connector with a pin 1 ofobject the input a metal like a connector paper clip .with If you metal object like a paper clip. If you see some sort of dark and light see some sortscreen of dark lightis pattern on the , the and monitor pattern on the screen, the monitor probably OK. Look for continuity is of probably continuity of the videoOK. leadLook back for to the main PCB. the video lead back to the main PCB. f 1l