Fixing A 1980 Atari Centipede PCB Another Tech GAVE UP ON! Classic Arcade Game Board Repair

[@ginkumpow3726]

Recognizing the symptoms of something not working is way more valuable than completely understanding how it works.

[@LyonsArcade]

That's a good point :)

[@smeatr0n]

Love these videos, I’m picking up a centipede next week which hasn’t been powered on for 30 years so I’ve started doing my homework in case something is funky when I get it home. Thanks for documenting this process!

[@MrMattDat]

Very cool. They used to make kits (pins & removal/installation tool) to replace those AMP pins. Now, finding one of those kits from the 80s is the challenge!! (BTW, very nice job fixing that connector!!)

[@LyonsArcade]

Thank you Matt! I'll bet somebody still has those pins..... thank you for watching!

[@MrMattDat]

@@LyonsArcade In watching the rest of the video, I like your solution better. Stronger with more material connecting. Great job!!

[@utubechannel8670]

This was a really interesting fix. You guys proved you don't need much basic electronics knowledge to fix basic electronics. Just enough to get by is all you need. The descriptions of what was going on in the circuit were almost complete nonsense, but you fixed it and that's all that matters. Top marks for enthusiasm.

[@LyonsArcade]

you sound like a really fun guy at parties

[@utubechannel8670]

@Joe's Classic Video Games I am. HAPPY new Year!

[@garbleduser]

My friend Donna Bailey coded Centipede. She is an amazing person!

[@LyonsArcade]

I always tell customers Centipede was coded by a woman and she must have known something because it's a very popular game with women! I always thought maybe it was the colors.... tell her we said hi!

[@garbleduser]

@@LyonsArcade Will do!

[@jussikuusela7345]

Nice fix! If I understand the counter right, it is a binary divider. Technically the "2" output would change state every time the chip receives a strobe pulse, the "4" output would change state every time the "2" output cycles once, and so on, so every output would pulse at half the frequency of the previous. The probe even produces a "beat" tone that somewhat correlates to the frequency of the pulsing in a certain range. The composite output woud have some of the H sync pulses masked out by the V signal and the AND gate, so every time a few consecutive H pulses are missed the monitor would restart drawing from the top. Now that there is no gap in the H signal the monitor will just constantly draw the stuff that comes out of the color lines. Also it will draw transitions in video RAM content, as normally the V blanking would turn drawing off while the video memory is edited. So it makes full sense to use the same counter signals to access the video RAM during the V blanking. Otherwise you would occasionally see part of a character in its old location and the rest in the new location.

[@LyonsArcade]

Thank you for the explanation Jussi, that makes sense (kind of) to me!

[@jussikuusela7345]

Was "a bit" wrong (twofold) and edited. Every divider stage would change state when receiving a full on and off cycle from the previous one.

[@joemieszczur9735]

great video. for those wondering, the line over the words on the schematic means: "active low". which is just basically inverted output, when its "on" its 0V and "off" is whatever the high voltage is. "not" is a great way of explaining though.

[@LyonsArcade]

Thank you Joe I appreciate you watching!

[@InMyHead]

I have MISSED these arcade repair videos!

[@LyonsArcade]

They're back :)

[@Joentje-fv9ho]

You say you are no "technical guy" but I think you are doing it great, greetings from a professional electronic repairer ;)

[@gavinw5592]

You probably already know this but those AMP connectors and pins at 2:38 appear to have availability at Digikey. Look for 583859-3 and look to the bottom of the page for associated products. Thanks for the continued content...

[@LyonsArcade]

Thank you Gavin!

[@TheTkiller9999]

Hey I just noticed that if you pause the video... the monitor looks correct.... you can see the high scores and the mushrooms etc.... (maybe you can use that as a troubleshooting technique in the future)

[@LyonsArcade]

Thanks Theodore, I'd never tried that... good idea! Thanks for watching too!

[@davevario]

FYI Line over a label means "inverted" as in the opposite state.

[@LyonsArcade]

Thanks davevario!

[@ronaldjensen2948]

@@LyonsArcade And in electronics school they taught us to say "not" instead of "with a line over it". ;) "horizontal sync not"

[@memyopinionsche6610]

Just wanted to say great job on the F14 TOMCAT. Looked a lot better than I imagined.

[@LyonsArcade]

Thanks, we appreciate it!

[@wackyworldofwindios3476]

good morningJjoe. you sure have saved a lot of old Atari's. Great job.

[@LyonsArcade]

I love the Atari stuff the manuals and schematics are so thorough they're really fun to fix.

[@KaPH33n]

I use the b/w output to display an image on my pvm with my test bench. You can also just cut an rca cable and plug it into an old tv. There's two test points to attach gnd and video. It's nice because you can see if it boots with just 5v and a tv.

[@juliusheide3643]

i don't know if you are aware, but if you pause the YT video at 10:00 is like you say, the 3 images you speak are there still and very clear.

[@LyonsArcade]

Thank you Julius!

[@NivagSwerdna]

How exciting... haven't seen an Arcade PCB repair for a bit... yay!

[@LyonsArcade]

Thanks Nivag!

[@Tranarpnorra]

You can go so far with experience but a good schematic is a godsend when troubleshooting. Nice work Ron! Especially since you always put yourself down as a not educated repair man. =) I would hire you just because you have the thinking faculties/knack for it compared to many people I have met that ARE educated with some piece of paper to prove it. And, yeah, they were not up to the task, paper and all. Thumbs up as always.

[@LyonsArcade]

I keep saying this, but I had an old man tell me one time while he was laughing "A good education will teach you how to spell Experience."

[@Tranarpnorra]

@@LyonsArcade Haha, good one.

[@yesitreallyisme]

seems to me that a few repairers have tried to fix this old girl, to my shame I bought a broken one but never got around to fix her and was a coffee table for a few years before I sold it. Well worked out another one repaired and given a new life by the pair of you.

[@LyonsArcade]

Yup, it's good to see them back up and running, thanks for watching man!

[@raywood8187]

Imagine the syncing feeling the other tech had when he couldn't fix it. An oscilloscope would be nice to have to look at those little square horizontal waves and see what's really going on in there.

[@LyonsArcade]

Yeah I hate when I can't fix them, i'll bet he was disappointed... oh well the board lived to see another day! Thank you for watching Ray!

[@b.o.353]

My wife loves Centipede. Whenever we get to an arcade that has one she has to play. Then when she’s done I’ll always play and beat her high score BUT I never tell her. Happy Marriage. Silent satisfaction.

[@LyonsArcade]

It's a really fun game, very well designed!

[@paulmichaelfreedman8334]

I have the same but with millipede. I tweaked the CRT emulator specially to play Millipede on MAME with a 26" 5K LCD (and trackball of course). It looks **EXACTLY** as if it's a CRT, it looks so real my brain even curves the screen as if it's bulging like the 80's CRTs. Every CRT RGB phosphor pixel is emulated with a grid of approx 20x20 LCD pixels.

[@AvengerII]

I have noticed women seem to like Centipede quite a bit. It was one of Atari's golden age (1977-1983) games and even today it plays well. I used to have it for the Atari computers... I owned an Atari 800 for years. Centipede was one of the 400/800 games my parents bought for me on cartridge. Back then, the personal computers were MUCH better for games than the older generation consoles like the Atari 2600 and Intellivision. I think the Colecovision was one of the first quality consoles that did close to arcade-perfect ports but it was released not long before the game crash of 1983. I'm amazed we haven't had a video game industry correction since 1983. We're long overdue because the current industry is being VERY OBNOXIOUS towards its customers. This won't affect the retro-industry as much. There will always be a place for old hardware and games. Most of us will never own these old arcade machines but there are enough people who own businesses (bars and mini-arcades) or just want to have these machines in their homes for nostalgia.

[@funcamp_ltd.]

@@paulmichaelfreedman8334 are you using hlsl for the crt effect? What are your settings?

[@paulmichaelfreedman8334]

@@funcamp_ltd. Yeah, HLSL. too many settings to put down here, sorry mate. My config contains every single setting possible in MAME, so it's big. But if you send me an email, I'll see what I can do for you.

[@andymouse]

Nice work, I love this game, one day I'm gonna get one, after I get a Defender !.....cheers.

[@LyonsArcade]

Defender is so cool. Way too hard for me though :)

[@jasonlarnach6770]

You don't just fix stuff, you FIX STUFF.

[@LyonsArcade]

That's very kind of you to say Jason, thank you for watching!

[@establishment1188]

I flipped centipede for the atari 2600 as a kid, it flips through all the colors and looks like the beginning but you are still playing and have control. I remember thinking it reset but noticed that the controls still worked.

[@buddyweiz]

As long as you say "MicroFarad' everybody is happy! 😉👌 Nah, just kidding! Say whatever you like! Cracked up a can of beer and enjoying the ride! Keep up the good work! Cheers! Oh yeah, Hello from Finland, the city of Turku!

[@PlumGurly]

The line over it (or a / before it) means the signal is inverted, so active low. On binary counters, that is one way to divide frequencies. So the CPU clock is likely sent to the counters, and the correct frequencies are tapped off. A counter count once per high/low transition, so the lowest bit would be half what goes in, and the next one is half of that, etc. Now, the reason both directions were screwed up is that the vertical is derived from the horizontal. Notice the line going to the other counter pair. That is the carry out on one chip and carry in on the other. So the other bank divides the 15,750 Hz or 31,500 Hz (whatever the horizontal is which could be between the 2 numbers I gave, like around 22-24 Khz) down into the 60 hz. So if the higher frequency counter is messed up, all the other counters past that will also be messed up since they chain the carry signals. Having one bit messed up would cascade to all chips that are connected through the carry in and out lines.

[@senilyDeluxe]

When I saw the picture it reminded me of a Quadrapong I did once (which had only 120 games on it and of course no CRT burn). Here the video address generator was broken in a non-noisy way so I could get the picture to sync up to four playfields horizontally and two vertically (or something). I couldn't find schematics for it so I went looking for counter ICs and... just piggybacked them. Turned out, they used 7493 in the middle of the board and one of them gave me one playfield when piggybacked, so there you go. And then we spent the rest of the evening playing Quadrapong. Awesome game, a lot more fun than a the player PONG table we had! Also iirc the first game where you had "lives".

[@LyonsArcade]

I've seen that happen on Centipede and Pac-Man, where you'll get multiple screens because one of the signals is missing, very weird!

[@senilyDeluxe]

@@LyonsArcade Yeah, had a Galaxian where there was no picture and no Carry Out from the first H-counter. Then I got two pictures with half of each missing ("ARE GALNS ION: TROYEN" instead of "we are the galaxians mission destroy enemies") and the game played at twice the speed, the first vertical IC was only counting 0-7... (and the LS174 in the bottom left corner with the weird failure mode of just slightly high impedance inputs, rendering the entires screen red (with bits of blue).

[@pezjohnson]

Smooth and swimming. Thanks for sharing the process. Great video was always.

[@LyonsArcade]

Thanks Pez we appreciate you watching buddy.

[@Mazwreck]

Great repair, I stopped taking on "had a go" pcbs due to various reasons. A couple ive had in the past were that messed up, work done and parts replaced for no reason only to find the issue was a socket issue.

[@LyonsArcade]

Yeah I run into that often, sometimes on my own stuff (LOL)... depending on the severity of the problem, after awhile I stop trusting stuff I've already swapped!

[@Mazwreck]

@@LyonsArcade This board you fixed reminds me of this Jail Break bootleg i had for ages, Had a sprite issue anyway long story short was a failed 74LS245 but it looked ok on scope, Tested Ok on 4 ic testers but just wouldnt not work correctly in circuit. Just for the heck of it i tried it in a other PCB that had a socket 245 and caused problems on it also.

[@FloppyDiskMaster]

I’m glad your thumbnail got Filter stuck in my head lol

[@LyonsArcade]

AWAAAKEEE ON MYYY AEO PLANNNNNNEEE kzbin.info/www/bejne/bmTGh2iXi52SlaM

[@nickkrug8157]

Just Pleasant and awesome at the same time !!!!!!!

[@waltergooeyblob]

Hi Ron, great videos! With that faulty counter the frequency/tone was increasing with each pin whereas the good one was decreasing 😀

[@LyonsArcade]

I didn’t notice that! Good stuff thanks…

[@WinrichNaujoks]

I love PCB repair videos!

[@LyonsArcade]

Well we LOVE that you LOVE the repair videos Willi, thanks for watching!

[@SeersantLoom]

This logic probe looks quite useful. It could be improved quite some ways: - the tip (just a screw?) looks nasty nasty. I like fine sharp tips much more. Especially if they are easily replaceable. - while 2 LEDs for low and high signal and tone generator are fine and cheap, I would suggest stepping it up a little. There are small/mini OLED diplays and quite fast microcontrollers with built-in ADC-s and they cost maybe 10-20$ max. So you could build a little oscilloscope right into the probe! It does not need to show exact voltage or frequency or support extreme voltage ranges, just a approximate waveform would do.

[@LyonsArcade]

That would be cool to have, thank you Seersant!

[@BTom16]

I love your channel. Thank you for the great videos!

[@LyonsArcade]

Thank you Tom, I appreciate you watching!

[@patrickmorrissey2271]

You say you never went to school, but you're pretty good at this....

[@LyonsArcade]

We try!

[@northtustinsteamworks5172]

Great job!! I'm living vicariously! Little battery operated oscilloscopes are super cheap now. Time to upgrade your tools?

[@bperkins]

Nice to see an arcade repair. Thanks!!

[@LyonsArcade]

Thanks Bob, we appreciate you watching as always!

[@johncrunk8038]

I have a box full of "bad" counter chips. Most of them are not bad, but had a bad solder joint. But you may as well replace it if you have to get out the iron.

[@10100rsn]

Pin 15 on N2 is the one that feeds the next counter. The other lines feed the address to the ram so the right data goes out to the monitor. Probably the output on pin 15 or one or more of the input pins on N2 went bad. They definitely sounded different after the repair. Hope to see it fully restored. The wave should be square not smooth...

[@kevinjbakertribe]

Yes - that is the carry out signal to the next counter. The counters are synchronous - both chips are run off the same clock, but the second counter only counts when the first counter indicates "carry out" just before it goes back to 0. I suspect that carry out signal was defective, causing the second counter to count incorrectly.

[@PlumGurly]

@@kevinjbakertribe Alternately, there was a dead data line, making the count wrong, causing carries to output too soon.

[@opticaltrace4382]

Sure you could hear the difference on the probe. I was screaming at you that the lines were stuck 😂

[@LyonsArcade]

I could hear the difference, it was very imperceptible :)

[@rickpontificates3406]

Easy to tell if it’s a monitor problem by scoping the composite sync and checking for 15,360 Hz. If you have good sync then the video should be locked in clean, whatever the image happens to be. SKIP those unreliable edge card connectors and hard solder wires directly to the fingers of the PCB and switch the connector to an off-board MINIFIT JR type connector

[@robwebster7406]

Thanks for the vid, if I remember rightly when the line is above something it’s active low and when the line is at the bottom it’s active high 😏

[@LyonsArcade]

I think that's right... but most of them dont' have a line at the bottom

[@naytch2003]

Love to build my own arcade machine one day..hope y'all are staying cool during the heatwave you guys are having up there🔥

[@LyonsArcade]

Donnie bought had a heat stroke yesterday painting, he took it easy for the rest of the day :) I'm stuck in the AC so i'm doing just fine, thank you very much!

[@naytch2003]

@@LyonsArcade a terrifying thought just came to mind..gnomesteader in shorts lol

[@Sarge395]

The master at work.

[@LyonsArcade]

I wouldn't call myself a master but that's very nice of you to say Sarge!

[@nathansmith8183]

This is such a great video! Thanks! When you think about audible frequencies, you'd expect the lower frequency to have a lower pitch. When you first tested the old counter, the pitch was actually going up with lower frequency pins, and after you replaced it the pitch went down as it should be. By the way, does AMP stand for Amphenol? They were very big in the telecom market, maybe there's a source for new pins/parts in that part of the universe.

[@LyonsArcade]

Yes that is the same Amp, they did a lot of the connectors for the jukeboxes too! Thank you for watching Nathan and the tip about the frequencies...

[@levelmeans-flat734]

Another awesome video!

[@LyonsArcade]

Thanks Level!

[@jmziprick1]

13:24 I'm an engineer and I love these videos lol

[@LyonsArcade]

Thanks Jeremy, we appreciate you watching :) Nothing wrong with engineers thank god we have 'em... just something wrong with SOME OF THEM lol

[@rfdave3980]

If there was no hsync coming out of the d latchs why would you change the second counter if the first counter feeds the d latch?

[@LyonsArcade]

I don't remember the specifics of this repair RFdave but i'm sure you've got it all figured out better than I do, thanks for watching!

[@rfdave3980]

@@LyonsArcade No Joe I don't just curious is all. I thought you may have know a reason. Thanks for the Videos. Interesting to watch.

[@drjmansplace5174]

Ever tried Mouser and Digi-Key for parts?

[@LyonsArcade]

I have, we usually order from Newark because they're here in South Carolina, so if you order standard shipping you still get it the next day. Thanks for watching DrJman!

[@drjmansplace5174]

@@LyonsArcade Shopping local is a great idea. I too shop locally whenever possible.

[@stevepearson7745]

Nice song reference for the title. Trying to sneak one by me.

[@johncantrell614]

Is that a screw you are using as the probe tip on your logic probe, or is that tip threaded to screw a slimmer tip on it? Was thinking it might have been a field repair for a broken tip….. By the way, if you are self taught in this stuff, you surly have done a good job in how you learned it, I do love watching the nice, logical, step by step approach you use in your troubleshooting!🙂📟🕹

[@LyonsArcade]

Yes the tip broke off this one so I put a small screw in it works pretty good but I might grind it sharper :) Thank you for watching John, we'lll do another repair video soon :)

[@johncantrell614]

@@LyonsArcade I don’t know why I kept noticing it, other than the one I bought to try to learn on had a nice pointed tip on it for getting into tight places. But then again as an active marine electrician, I have seen quite a few of those kinds of field repairs on meter leads, and other things that were not pretty, but “good enough” 😂. But hey, beats buying a new one if there”s nothing wrong with the rest of it! 👍

[@rickpontificates3406]

Ahh, the NOTORIOUS jumbo capacitor on the Atari power supply! Always made me laugh how Atari literally filters the output of the bridge rectifier with a SINGLE CAP!

[@PlumGurly]

It is funny that there is a brand called Big Blue, and yet, their capacitors are black.

[@daveweston5158]

Hi Ron! Point of curiosity; When troubleshooting a board set, like this one, and you run across a suspect, non-socketed chip for which you have a replacement in stock, and on hand, as a matter of course, do you simply socket the board, and replace the chip, or do you first piggyback the known good chip onto the suspect chip, to see if that corrects the problem? I've seen both approaches, and both are certainly valid, but I was wondering if you had a preference.

[@LyonsArcade]

I try to figure it out with the probe, and then if i'm relatively certain that it could possibly be the problem, I swap it. The problem with piggybacking them is if you have a stuck output or input it might stick the same input or output when the piggybacked chip touches it, so it doesn't always work and you're left in the same position where you don't know. So if I'm thinking it may be one I usually just swap it, sometimes depending on the situation I'll piggyback it just to see if it changes anything on the screen or not...

[@robertthompson728]

Leetle Son of Beach chip! ;)

[@LyonsArcade]

I got 'em! Thanks for watching Robert!

[@simonphelon7221]

Can't beat a Big Black Capacitor.

[@WinrichNaujoks]

Just try not to lose it.

[@yowl00]

Nice. Have you got one of those usb scopes, I ask because it looks like you preferred to replace a few chips rather than look at the output signals? I don't know how good or fast they are, just asking as you have lots of experience.

[@LyonsArcade]

Oh that'd probably be a muuuuch better way to do it

[@slyfoxkgar]

When you pause the video, you can see the 3 redraws of the same thing. maybe should try that some time to get another look at it. does not fix it.. but may give you more info

[@LyonsArcade]

Thank you slyfoxkgar!

[@robinbirmingham9221]

We live in a backward world, Ron. I'm a proud southpaw as well.

[@LyonsArcade]

My man

[@NivagSwerdna]

Most modern-ish multimeters now have a Hz setting.... you can use that on the H and Vs and check frequencies... hoping for 15kHz at H256 and 60Hz at V256... or something like that... doubling as you go down. Just sayin'.... did I just say... "I wouldn't have done it like that"? No I didn't. Good job!

[@LyonsArcade]

Ahhh, that's actually helpful I didn't know that. I'll bet my meter might have that...

[@frankgagliano9677]

The mpu board looks like a mpu board from a pinball machine except a lot bigger, is it? Is the power supply the same way? Great video Ronnie, Gorgar is still talking.

[@LyonsArcade]

It's not the same exact design but yes the same general concept! The power supplies in arcade games are a little simpler, they only need the voltages to run the game board, and the sound amp... on a pinball machine you need different voltages for the board, the sound, the lights, the coils, and the displays... so the pinball board necessarily is more complex.

[@edward4191]

Ron , I am wearing my Play at Joes T Shirt and I was wondering do you actually have an Arcade where you can actually play games or do you just sell and repair Machines and Games ?

[@LyonsArcade]

We just sell and repair them, but we have a bunch set up in our shop that people can 'test' :) Our store is a vintage video game store, we sell all the old console stuff and also Arcade games and Pinball Machines and Jukeboxes, plus we repair them. Vintage video game stuff, we either sell it or fix it or whatever... thanks for repping our t-shirt, we appreciate it Edward!

[@edward4191]

@@LyonsArcade Love the T Shirt ,no problem !!

[@gibbonsdyson5337]

N2 was reversed based on the sound of the pulses.

[@LyonsArcade]

Thank you for watching Gibbons!

[@youvsyou945]

Right on man, keep them arcade repairs/restores coming! One of my fav. channels, great vid...thanks. Man that's weird that amp connector/pins was on there.....All my Atari Games had the 44 pin molex stock(like the smaller pcb connector there), that can't be original.

[@LyonsArcade]

it was original, they kind of went back and forth on the earlier games... we run into it every fourth or fifth machine, that connector just succccccks!

[@youvsyou945]

@@LyonsArcade WOW, that's neat....thanks for commenting yeah the pin surface area seems small compared to the molex...., I've never came across one with that connector, My Tempest/AD/Space Duel had the molex.....Very cool game here, Atari made high quality cocktails for sure and Centipede will always be a classic/fun.....Have the Team Play Centi/Milli/MC which always gets lots of play when I have folks in my arcade...will always be a fun game! Not a lot of burn on that tube, man this is going to be a nice game when y'all are finished....Look forward to the next video with it fixed. Thanks again for the vid and commenting!

[@elitster]

Favorite game

[@LyonsArcade]

It's one of the top few for sure!

[@jasonmushersee]

i think there's a version of centipede on my old nokia phone. i know what you mean, good schematic makes allllllllllllllllllllllllllllllllllllll the difference

[@LyonsArcade]

I probably mentioned it, but the early Atari schematics were even better than this, they even told you what each line was DOING, much less where it was going! If you ever get bored download the schematics to Stunt Cycle, the early Atari game that was kind of an Evel Knievel rip off.

[@snotbubbles3276]

Damn your shop is a pig sty. Love the content.

[@LyonsArcade]

Tell me about it :)

[@mykalimba]

31:45 I'm not convinced that you really understand how that circuit works. That's a digital circuit (at least the part you're looking at in the schematic), so there's no analog wave that's happening there. Everything happening at that stage is happening (or supposed to be happening) in a square wave, not a "swimming" sine wave.

[@LyonsArcade]

Hey genius I can’t make a square wave with my hand so you’ll have to use your imagination a little bit

[@donsurlylyte]

you have to buy bigfurcated to get the big bifurcated

[@808zhu]

Don't trust prior work. Sorry - not sorry.

[@LyonsArcade]

Pretty much! In this case however it was all done right but I still had to check!

[@808zhu]

@@LyonsArcade You've got the touch.

[@Jimmy83-i3g]

Watching

[@troyleong7412]

Cool fix. Why is the language in Spanish? Can that be changed to English???? COME ON PEOPLE!!!!!!!! ;)

[@LyonsArcade]

Yes depending on what the dipswitches are set to on the game you can change the language, I think it does English French German and Spanish! Thanks for watching Troy!

[@nicwilson58]

Throw the logic probe away and get yourself an oscilloscope

[@LyonsArcade]

I don't throw things away and I have three oscilloscopes on the shelf behind me, anything else you want to complain about? Thank you for watching Nic.

[@Jimmy83-i3g]

Hay Ron help meeeee!!! Lol Iv emailed you