Multiple Monitor & PCB Repairs on a Space Invaders Deluxe Arcade Game

ladies and gentlemen this is Joe's classic video games back with another cool arcade game repair video for you today this is a game that we had a while back as space invaders we seems like we get space invaders in all the time space invaders deluxe that we sold to a gentleman friend of ours who has arcade and he's been operating it for a while I don't know how long he's had it but so he's been saying that it's got some issues where it's resetting or it doesn't come up or sometimes it'll come up and play and then we'll stop working after a while order so what we're gonna do is we're gonna troubleshoot it a little bit and see if we can figure out what's going on with it so the first thing I'm going to do is we'll pop the backdoor off and look inside just to make sure everything's in place before we plug it in so we took the backdoor off and one thing I see immediately as this came loose so this is the ground it's supposed to go from here up to the tube so you have this little thing here and this goes right there BAM not sure that would have really caused a problem though but that's what's going on and then you have the game board here everything looks plugged in properly this particular one has had a new power supply put in it you can actually put a switching power supply in these cabinets in place of the original style there's a screw sitting there and of course we got our two fuses here so I don't see anything that's out of the ordinary where you wouldn't want to plug it in so we'll we'll plug it in and see what we get out of it we plugged it in and these have an interlock switch a lot of games do basically when the back door is on it holds the switch in which gives a power and the reason they do that is so that in case the back door gets pried off or falls off or whatever kids won't get electrocuted playing in the machine so whenever you're servicing on one you need to pull that out which is the same as it being pushed in so usually it's in the middle when the door is on it holds it in or you can pull it out if you're servicing it so we've got it out and then the power switches up here on top of the cabinet so we'll turn it on or we'll try to I didn't sound good our light is on so it's making a bunch of noise it doesn't sound that great let's see if we get anything on the monitor these monitors take a little while to come up and do their thing no I think our monitors messed up I don't see any neck glow on it so basically normally the neck should be glowing orange and it's not and things look a little crooked it may be that the tube is screwed up let's see if we can play it without seeing it I hit the start it's up and playing kind of Sam sounds are a little messed up all right so the game is playing it's just you can't see it and it's making a strange sound whenever you turn it on so let's turn it back off let's look a little closer at that neck on the monitor that doesn't look good at all man what are they doing to me here so whoever put this back on can you see that one pin how it's bent over out of the way it's not in the right spot I don't know if it's focusing properly see the one pin is bent sideways so that's definitely an issue so I'll try to carefully Bend that back and then slide the the socket back on it and see what we get so I straighten up the pins best I could and I got the socket back on how it's supposed to be but whenever you turn it on you don't get any monitor so I have hooked up our multimeter to the monitor power and the monitor is getting power it's just not coming on so next thing I'm gonna do is pull out the monitor chassis and see if there's a few or something that burned up okay so I pulled the monitor chassis out this is a Motorola kV 700 a black and white monitor chassis the fuses are under here but they're not blown so this thing as you saw wasn't doing anything so start looking at it and there I see this this transistor here q18 that has like oil all over it let's see what I've even did with it drop it well it's here somewhere anyway it's a tip TI p32 a transistor and so this is a TI P 32 C transistor so I look it up to see if this 32 C is the same as the 32 a and so looking around yeah this is just kind of a higher power version but the pins don't line up right and so the middle ones a base and once a collector and one that's an emitter and it's labeled on the board collectors on one side emitters and outside the bases in the middle well on the tip 32 it's not like that the base is on one of the ends so I'm thinking why is there a tip 32 in there that doesn't even make any sense that you know they didn't have them back then so and so this is an old monitor that's from the 70s so I find the schematics and look it up and that's supposed to be what Motorola called an a 2 J transistor motorola used their own transistor numbers and then didn't tell anybody what they were right so you can't buy an a 2 J transistor you have to figure out what it was well somebody has worked on this monitor and put a tip 32 in there and it ain't right that's not what's supposed to go in there so an a 2 J other people have figured out is actually a 2 in 4,400 transistor so somebody for whatever reason and this is all in the power supply too by the way so without this working nothing would ever power up somebody has put the wrong transistor in they're working on it whenever I took the the monitor out all of the screws were missing out of it so somebody's had this board out of there working on it so they must have sent it off to somebody and they didn't know what they were doing and then if you look look I haven't looked this one up yet so we got the same thing going on there someone has put a tip 32a in right there which that's not the right transistor band doesn't add up see how it says on the board collector on one side and emitter on the other side that's not how a tip 32 a is even configured so that chips probably wrong so I checked all the fuses are good the the the three transistors mounted on the side are still good no problems I can't find any resistors that are burnt up but then as I'm working through the power supply section I can't find the diodes are fine resist respond resist respond as I get over here that's the wrong chip I'm in the wrong transistor so that's a big no-no so it might have burnt up some other stuff these this one resistor that connects to it here it looks a little weird so I'm gonna check that on the schematics so I'm just checking through the power supply section and see if I find more stuff that looks like it's been tampered with there replaced and checking all the resistors to see if anyone's burnt up because we got a situation where there's no power so I get this big resistor burn up you know the power we can get through it and so you wouldn't get any action so either something like that's going on or this transistor being the wrong one that could have definitely done it so I'm gonna keep working through it and see what we run into basically the way these work is they create a power a voltage that comes onto the board and then it runs the the flyback which creates several other voltages that runs everything else so if that main voltage coming in a screwed up nothing will work and we still could be in a situation where the the tubes broke or something so but we got to get this at least glowing first where we plug it in and it makes a bunch of noise or something to tell us that the tubes screwed up but I'll keep working through it and see what else I can find so there's the two transistors look how this thing's got like grease and oil all over it all you know what happened there I guess it burn up I don't know but I don't even know what happened they had replaced one of the power supply transistors with the wrong one and then they had replaced one of the horizontal deflection circuit transistors with the wrong one Salomon you look in the manual and it tells you Motorola's code number and then if you search around online you see the cross-reference so this is supposed to be a 2 in 3440 and they had put in a tip 32 which isn't anything even similar and then that one was supposed to be a to end 4,400 and they'd put in the tip 32 same thing Oh and I looked around I couldn't find any resistors or anything else fried so it could be that we've got a situation where the tubes bad or broken and it screwed up some stuff on the board and burn up a couple transistors and they found them but put the wrong ones in and so now whenever we turn it on we're not getting anything because those transistors aren't right or something I don't know but I know one thing we're gonna go try it back in the machine so we'll see if it does anything okay so we have mounted the monitor back in I'm gonna hit the power switch let's see if it sounds different now the tubes cracked if we're getting power if the tubes cracked what you'll hear is like it's like all kinds of crazy stuff coming from the tube which is basically air hissing in where it should not be so let's see what she does may hit the power switch okay I hear how voltage yeah look real close at the neck do you see the neck look let me see if I can get a good video on it you see the orange in the neck that's what you want that's the heater voltage well I'll be damned well our tooth wasn't broke it was just for whatever reason they had put two of the wrong transistors in dad's crazy I don't even understand how that happened so you saw what happened you saw the let me turn off the lights because it'll look better here and I'll show you the neck glow a little better maybe links it from the back better with the lights on okay so you saw what happened it wasn't working monitor wasn't doing anything I checked real close a couple of the pins were bent on the neck board I'm on the tube so I replaced I straightened out the pins and put it back on we're getting nothing no net glow nothing so I take it in the backroom start looking they've obviously replaced two transistors and that was all that it looked like it been replaced that they had replaced the two transistors with the wrong damn transistors weren't even close they had gunk on those two transistors that look like oil or something took the two transistors out put the right ones in BAM the monitor comes right up that's one of the weirdest ones I've done folks let's see if we can adjust the brightness knob is right here on these so basically you turn it up until you can see the background and then you turn it back down that's about as bright as you can get it awesome so let's point it up and I believe it sounded to me like the thump-thump thump-thump thing is gone right so we have done how many videos now showing you how to fix Space Invaders sound problems looks like this is gonna be another one so no thumping so nope no background sound so what i'm gonna do is i'm after you make like 30 shots or something something like that excuse me how do you make like 30 shots or something is when the guy comes out okay so the explosion sound works the UFO sound works hmm so the thumping came back after a while so what's a let's look at that sound board a little bit close to safe or something not making good contact or something so here is our second is the board that makes all the sounds it has a sticker up here where it's been repaired by eldorado games about ten months again so at one point this thing worked fine so you can see they replaced a chip here which is actually I think that's the preamp and then this is the sound amplifier then you've got a chip here in a socket so I'm wondering let's look on the schematics there's a basically this motherboard sends a signal under the board and it makes off sounds work so let's look on the schematics and see what area does that if it's this socketed chip it may just be dirty or something but I think it it might read this one so let's check out the schematic see if we can track down why the thumping doesn't work and then comes on after a while and just for completeness sake this is the the schematics of the manual that I was looking at q18 is one of the transistors that they were replacing you can see this is in the power supply section which creates 273 volts in the 12 volts so this transistor is a 2 J and they had replaced that with a tip 32:8 we put the right one in and then come down to this is q8 this one had also been replaced with the tip 32 a but it's not a murdered roommate it's an a 5 F which is a 2 in 3440 completely different nothing like it so we replaced this one with the right one and apparently that's what fixed it so let's scroll through to the sound alright so we've done several videos on how to fix sound in space invaders so basically what you have in the schematics is these are signals coming from the main board and they go through a big socket on the edge of the thing so it could be that it's trying to send the signal through and it's not making good connection because that sockets dirty or something so we're gonna remove the daughter board and plug it back in just in case and then the signals run over here and they run to these two chips not showing that good so it runs up here to this chip which is a 74 174 at efore and it runs to this chip which is a 74 174 at e5 I believe that says okay and so the data lines run to both chips so if it was a bad connection down here these are the four lines that make the thump thump thump thump thump thump thump right here right so if it was a bad connection from the socket you would probably lose one thump you follow me because there's four different lines that trigger the four thumps and they all run through these resistors and they all run through these diodes and then they run over here to this 556 timer chip and then they run through this m3 and there's a couple caps here involved in things like that okay and then those same data lines the same ones that make it do the thumb thumb are these d4 d3 d2 and d1 lines they also run up here now d1 comes over here and it let's see what it does I don't see what it does d2 d2 runs through here and makes the missile sound well all of that's working fine and it never fades in and out d3 comes through here and it makes the explosion son sound well that's always working fine and it never fades out and then d4 comes through here and it makes the invader hit sound which works fine it never fades out so that kind of proves that d1 d2 d3 and d4 all work fine so then you you come down here to e5 and you get the same thing going on and then you've also got d0 is handled by E 5 so d0 runs the saucer hit sound well we haven't hit the saucer so we don't know if that's working right or not so it could be that this chip is acting up right because everything's common to this chip or it could be that this timer chip is acting up because the four thumps are common to the timer chip 556 chip or it could be that these capacitors are acting up because they're common to that too so what we're gonna do is we're going to pull it out we're going to swap these capacitors because that's real simple to do and then we're gonna pop it back in and see if that makes it work another thing that kind of makes me lean towards the capacitor is that it's heat related so when that first comes on it doesn't work right but then after it's on a little while it heats up a little bit it starts working right that's classic capacitor stuff capacitors change their capacitance value if they're going bad after they've been on a little while and stuff you know so kind of sounds like caps so we're gonna replace those two caps first and then slide it back in those would be real simple to change to will slide it back in and see if that fixes our problem and then I'll play it to and see if I can hit the saucer before the thump fades in so you know what I mean so like if the thump is missing and the saucer hit isn't is missing well then it kind of points towards this chip because that's all this chip handles but if the saucer works the whole time but the thump doesn't work for a while then it has to be something that's just common to the pumping but we'll pull it out first then we'll watch those two capacitors because that'll be easy so here is our timer chip our 556 chip someone has already replaced that is the one that makes the thump-thump thump-thump happen along with these four diodes here thump thump thump thump thump thump thump them and the caps that we are talking about that are questionable are these two caps actually right here because if you look on the schematics they're after h3 4.7 tantalum 10 MF tantalum which is these two caps so we're going to swap those first and then if you look real close at this 556 see how it's not soldered in there all that great see that top pin that's connecting it to the to the 5 volt I think so that would also cause a problem if that's like an intermittent connection so we're gonna re solder all that stuff now we could just replace that chip but once they've replaced it and that's a fairly new looking chip somebody's done it in the last couple of years once they've replaced it it's probably fun you know you're probably not going to have the same chip die on you right after it's been replaced you can see that bottom that bottom trace looks a little weird too so we'll reflow some of that stuff we'll swap these two caps out with nice new electrolytic caps and then we'll pop it back in there and see if that fixes our issue where it doesn't do the thumps whenever it's first turned on okay so I think we've got it so I've got it turned off all I did was replace those two caps irie flowed the solder on that 556 timer chip and I put it back in the machine so we're gonna turn it on and I'm gonna coin it up before the monitor even warms up we're gonna try to start it immediately to see if it's a you know if the thumping is is there from the very beginning yeah okay so we haven't tried all of the sounds yet [Music] [Music] [Music] [Music] the only one left is the extra man if you get one and the sounds are a little weird like this one when it shoots and hits them it sounds a little different than some of them that's because of the way the sounds are created it's not a digital sound it's an analog sound so it's we gotta get our even winter free [Music] [Music] [Music] [Music] alright so I test it again after the customer left just to make sure that everything was as I thought it was and it was true whenever I got a bonus missile base which is what they call it it did not make a noise now look at this it's h4 number the 556 timer which is the same one that makes the thump-thump thump-thump so we're onto something here people we've got our thump-thump thump-thump back but we don't have our bonus missile base but I just restored that chip so I probably messed something up I don't know I don't know if it was working beforehand though but so what I'm gonna do is I'm gonna go and use a multimeter and check all of these connections and then I'm also gonna check this cap right here - that doesn't look right all those money's already replaced it so I'm gonna check all the connections and everything and then worst case we might have to swap that chip again but I think it's just gonna be a bad connection and then if you look the output of it is right here it goes into this m3 this h3 chip which is also what this one goes into so we've got a problem with either h4 or h3 on both types of sounds I'm just gonna check all this with a multimeter and we'll see if that fixes our problem by the way this is the worst sound to have a problem with because it takes you it takes you a while but you have to play it for three or four minutes to get a bonus missile base to see if it's working or not but will a will multimeter it all out and see what we come up with so I went ahead and just replaced the chip it didn't like the way it looked I put a socket on it too like it should have had before and put a new one in and so we're gonna try it out we won't know if the problem was the connections or the the actual chip but we'll see if this fixes it hopefully so we need our thump thump thump sound to still work because it's controlled by that and we need our extra missile base sound to still work we're back up and running let's see if our thump still works yes now I was saying earlier if some of the sounds sound a little different it's because they're analog sounds they're not a digital recording so they're made with resistors and capacitors and little amplifier chips and you saw you saw the resistor is a slightly different value [Music] so we get three bases see it's a bottom shortly we will win another one but do you see how that happened was that the right sound was that the right sound so the noise I heard was from that but it also gave me an extra base but I didn't hear the sound so I still don't know unbelievable so you get one of 1500 points so we're gonna die and then try it again I think it's still messed up [Music] all right [Music] [Music] [Music] [Music] [Music] [Music] all right 15 other points here we come here we come people yes I got another base no sound we got to go back folks we got to go back so if you look on the schematics it actually works through this h3 chip twice before it makes its thing and I checked all these resistors all the resistors are the right value are close enough and then the thumb thumb thumb thumb also went through the h3 it very well could have been h3 so we have swapped age three it's a 74 11 so we'll we'll see if that gets us anywhere hopefully keep your fingers crossed people this video is gonna get really long if this doesn't fix it [Music] [Music] okay folks we've got two bases here we go we're close here we go all right how sweet it is [Music] it was the 7411 chip scene in a million times pretty wild huh but we got it going there so there there we go so we fixed the monitor and then we fixed the thump-thump-thump was missing and the other one was missing now it could be that that 7411 chip was the problem with both and it was just a after it was on a while that got a little better who knows but I think we're good now so if you liked the video give us a thumbs up now oh I was gonna say earlier I didn't fully explain it when these came out so the way they make their sounds as analog so they have resistors and capacitors and stuff Center do they do it with voltages running through an amplifier chip right so my whole point is resistors so say if say it was designed where in this one spot it needs a 1000 ohm resistor well they're never exactly 1000 ohms they have a tolerance so most time are 5% or 10% which means it can be 900 ohms or it could be 1100 ohms if there's a 10% tolerance well if you have a 900 ohm resistor in it and one board and an 1,100 ohm resistor in another board those two are going to sound slightly different wherever that resistor is because it's it's changing voltages and waves and things like that so if you get one of these and like this one the sound is a little bit different than some of the other ones I've heard if you get one of these and the sounds are just slightly off on some of the stuff you're not ever gonna be able to fix that because it's just minor little things so there you go leave your comments below tell us what you think give us a thumbs up like we said for taking the trouble to film it for you and we hope this helps you fix your space invaders or space invaders deluxe if you get one in and we'll see you on the next video