Designing the Centaur pinball replacement echo card.

[@pietzeekoe]

The combination of an expensive and rare glass pane precariously balanced on an inclined plane, high voltage and, Clive squished up against a wall gave me heart palpitations.

[@SillyKnob]

Me too.

[@JimPugh2014]

@@SillyKnob and me

[@maicod]

nice that you didn't edit out your annoyment when the machine decided to start playing on its own

[@thepvporg]

Yes, it did have "the balls to do it... " :P

[@xorinzor]

agreed, it fits his kind of humor so well haha :P

[@dr666demento]

I know I'd be flipping DIP switches to turn off that ''autoplay'' mode. Both due to the annoyance and to reduce unnecessary wear and tear. That said that ''autoplay'' is quite unique (mimicking video games ''attract mode''). I'm guessing he pots down the audio when not in use - because who'd want to be woke up at 4am with ''I AM CENTAUR!!!''. I was wondering when he do one of his pinball machines, keeping Haunted House in shape is probably even more difficult: en.wikipedia.org/wiki/Gottlieb has been gone for over 20 years now.

[@rambo1152]

Isn't the autoplay sometimes called the "barker" or "barker mode"?

[@peterjensen6844]

rambo1152 yes Barker is the correct term. Arcade games of all types do similar. But most pinball machines don't or didn't beyond the electronic ones just playing audio and effects (like Addams Family). It's rare to ones that actually fire balls.

[@BastiElektronik]

2:20 I really love the way he smiles as he imagines destroying that chip with reverse polarity

[@mitchelwb]

Miss my Centaur. My Say it Again board was still original and still working, but I remember looking at these and being glad they existed if I ever needed one. Had no idea it was your design! I sold mine about a year ago. I only have a few pins left now, and Centaur was probably the hardest to part with, but for the money, I just couldn't justify holding on to it to collect dust in my basement.

[@Fifury161]

Love these trips down memory lane! Thanks for sharing - and what generosity too by sharing your design freely!

[@kevindinsdale8204]

This is a quite amazing insight of your knowledge of electronics. I did not realise how talented you were.

[@buckstarchaser2376]

Spoken like a defeated game boss.

[@maicod]

I want a pinball machine with Clive's voice

[@lfpi07]

That would be an awesome DIY kit :)

[@sophiecutler9741]

Same!

[@SianaGearz]

And i feel it should be dolphin themed and the music theme could be "Big Fishes at Emerald Coast".

[@santi308]

And when you lose that sound of repugnance "Iugh" is reproduced

[@boesesascha]

Attracting mode: "Play me I'm quite interesting"

[@trickysoft]

Thanks Clive, another nice gift to the community.

[@icychill105]

pinball machines are not small and clive being half a head taller than his is amazing, he truly is big clive

[@BoxxerCore]

Poor old Maplin :[ ... I really miss that shop. I would go into the St Enoch Square shop every Friday and potter about.

[@IC225]

maplin....gone but not forgotten, always got stuff from there

[@TheRealBobHickman]

Had no idea that you were into the arcade scene too. Thanks for making this and also making it open source hardware. The world needs more people like you.

[@pifflebunk]

I used to service pinball machines many years ago and still like the old ones better. There's nothing quite like stripping down a playfield for cleaning. I still have a filing cabinet full of pinball service manuals. This video brought back lots of memories.

[@bryanlatimer-davies1222]

Rodney Walker I worked for MAM INN PLAY in the eighties and always gave the pintables a very thorough test after repair ok I just had fun on the company's time

[@MusicalBox]

Saving pinball machines all over the world. You are Centaur's little helper :)

[@therealjammit]

It looks like the SAD4096 used an analog bucket brigade. Basically it had a shit-ton of built in (tiny) capacitors made of silicon. It takes a sample of the input voltage and stores it in a capacitor (not digitally). The capacitor could hold that analog voltage for a little while. Internally an amplifier feeds that voltage on the first cap to a second cap, transferring that voltage to the new capacitor. The amplifier was then disconnected between caps 1 and 2, and another sample from the input was stored (analog again) and put in the first cap. By daisy chaining a bunch of these sample, transfer, dump functions you'd eventually get an output. The teeny, tiny silicon capacitors in the chip would eventually punch through, probably from electron migration.

[@ianhine4012]

Yep remember building reverb units with these

[@flatfingertuning727]

Guitar pedals are still made with analog bucket brigade devices. While there may be not be any current parts that are pinout compatible with the one used by the original board (the ones I know of are 8-pin DIPs) it would probably be possible to make an analog delay that would sound good in the machine. Or one might be able to slap some quarter-inch plugs on the wires from the audio board and use a guitar pedal.

[@nrdesign1991]

Oohh, so it's a time-discrete, but value-continuous device?

[@kargaroc386]

If it breaks from electron migration, would a NOS chip work more or less the same as it would've when it was made? From what I understand EM only occurs when in use.

[@stanleydenning]

That Pinball Machine was Top of the Line in it's day.

[@twjonckheere]

Old pinball machines are beautiful inside and out. I have a friend that works on them as well.

[@rinner2801]

I am quite envious. Thank you also for sharing the design that is very generous.

[@frantickoala994]

@bigclivedotcom as someone who repairs pinball and arcade machines as a living... Thank you for your contribution to the community.

[@FeelOfWartune]

Godlike work, sir. Your seat in pinball Valhalla is firmly reserved.

[@boonedockjourneyman7979]

Outstanding! Great to see your genius again. Your skill at shifting between generations in electronics is rare. Please do more. People need to know that you don't need an Arduino for everything.

[@jrb_sland5066]

Back in the dark ages [late '70s?] I bought a half-dozen SAD1024 chips [I needed only ~50 ms delay for a motion picture optical sound recorder application]. Try as I might, all of my breadboard experiments [including fancy differential/cross-coupled topologies] proved to have more distortion/noise than I was willing to tolerate in the primary audio path. A couple of years later I was able to fit our Vancouver studio with a second hand digital delay line to adequately perform my desired task. All this is ancient history, of course - analog audio has quite rightly been superseded by modern, ~noiseless, ~distortion-free digital mechanisms that are far superior [and cheaper!]. Many thanks, Clive, for reminding me of these early chips - I'll now search my dusty upper shelves to see if any SAD1024s remain...

[@spikekent]

Wow! That is an awesome machine, great work in resurrecting the voice. When it first started playing, the sound filled my whole house (literally) I had previously turned my volume and bass up and forgot to reset it, it made me jump more than I have done for a very long time ... then I rewound and played it again and again. Fantastic!

[@laser-sj]

Clive... just when i was getting bored of you taking LED lights apart... you do this ! Love it

[@schregen]

Clive, you're a smart, cuddly bear! 🐻

[@OtusAsio]

You bring back so many memories by opening this...I used to work with those many years ago (and repare them)...Thank you for sharing...

[@pepperspray7386]

I LOVELOVE the sound from oldschool pinball machines.

[@mulgerbill]

Grew up with that machine, always a line to play at the local parlour. Love your work and passion big feller, your willingness to share and lack of furious meltdown when shitbags pirate your freeware is the icing on the cake. That deserves a donation

[@joinedupjon]

11:00 smirky winking face in the power supply section

[@SomeMorganSomewhere]

Kinda surprised something of that vintage would use a solid-state echo/reverb, I'd have expected a spring reverb unit, though I'm not sure if you could get *that* level of echo out of one. Also "Say It Again Later", brilliant!

[@DrBagPhD]

Centaur's such a lovely table, I'm envious! Thanks for sharing, it was fascinating to get a better understanding of how the table works. I've often considered grabbing a table from the 80's but I doubt I could handle the upkeep for such a complex machine, so getting insights like these is fab :D

[@dieselwalter]

Our hero, just making the world a better place, one board at a time. Cool video, cool project.

[@davestobbart7203]

loved this Vid. as an 80's kid it smacks you with nostalgia and 2 see how these amazing machines work is amazing. cheers BC

[@PhoenixRevealed]

I began my lifelong love of electronics engineering as a pimply-faced teenaged hobbyist back in the early 70s (most digital gates back then were RTL, and TTL was just beginning to show up), and I was around when those old Holtek chips were the latest cat's meow. There were originally used mainly in musical instrument amplifiers to replace the mechanical spring delay lines which were required back then to produce echo effects. Those old devices used an electromechanical transducer to excite a tensioned spring usually about 12" long, and then converted back into an electrical signal at the far end of the spring with another transducer. Think of it as a higher quality version of those cheapo plastic toy echo microphones kids play with these days. Sound quality was awful but it was all they had to work with back then. These "new" fully electronic delay lines also proved popular with musicians for "phasers" and "flangers" which merged a straight-through audio signal with a delayed version to produce "spacey" audio effects. Since these Holtek (and other vendors) delay lines predated economical flash A/D converters, they used an analog "bucket brigade" technique much like CCD video cameras. The "4096" in that part number probably referred to 4K buckets in the line. The idea was to string a series of on-chip capacitors together with analog amplifiers and switching components so the voltage stored on one capacitor in the string could be dumped into the next one, thereby passing the instantaneous signal voltage down the line at the chip clock rate. Each bucket and its switches formed a tiny sample-and-hold cell. Since you can't simultaneously fill and dump the voltage on a bucket cap, you would normally need to dump the last bucket on one clock cycle then fill it from the previous bucket on the next, continuing on backwards to the first bucket in the chain before you could sample another signal voltage from the head and start the bucket shift again. With the technology of the day this would have limited the overall sample rate too much for quality audio on the output, so instead these devices used two parallel chains of buckets, call them 'A' and 'B'. On the clock's rising edge all the voltages in the 'A' bucket cells would be dumped into the matching buckets in the 'B' chain. Note that the very first 'A' bucket would actually be captured from the instantaneous signal voltage. On the falling edge of the clock, all the 'B' buckets were copied back to the 'A' chain, but ONE CELL CLOSER TO THE END than they were on the last clock cycle. This method meant that there was one voltage being sampled at the head and one voltage being dumped at the tail for every clock cycle, rather than waiting for all the voltages to "ripple" down the brigade from the tail back up to the head after 4096 clock ticks. My guess is that these chips proved short-lived because the on-chip bucket caps would degrade. All it would take is one failed (or even just weakened) cap in either chain to break the path of buckets from head to tail. If there was a big enough market to warrant it, these days it would be simple to treat the old bucket-brigade chips as black-boxes and produce new designs which flash-converted the input analog signal into digital (audio quality on these old chips was not stellar so 8-bits would likely be sufficient), and then use fully digital bucket brigades to shift the samples down to a DAC at the tail end to convert back to analog. As long as the specs of the ADC and DAC were properly chosen, the surrounding circuitry would have no idea that the signal was being carried down the brigade in bytes now rather than on caps holding analog samples. Since the bucket chains in these old devices was fairly short (4K in this case) you could probably duplicate the functionality with a cheap modern MCU with integrated ADC ad DAC and maybe a few extra analog components to massage the input and output signals to match the original support circuitry. Ah, the good old days of 70s electronics innovation. 555 timers and 741 Op-amps... fun times.

[@BergRD]

Great stuff Clive and welcome the more tech-heavy stuff!

[@ilaril]

Thanks for the trip down the memory lane! I remember that machine, and I'm the model variant from 1980. Those good ol' machines lasted so long.

[@thedevilinthecircuit1414]

Just like this machine--Big Clive is a legend.

[@matthewcarlrose]

Very similar to the Stern Meteor I used to own! These machines are a real joy to work on! Not tooo complex and they all run on similar hardware! :)

[@bigclivedotcom]

I think most of the pinball manufacturers based their designs on others. But each brand has its unique character.

[@Tedybear315]

Taking me back to when I started my current 'job' over 24 years ago. Used to be a pinball and arcade tech...Still am an Arcade Tech and General Manager now. All Good Stuff!!!

[@bigclivedotcom]

Hey Tedybear,. How ya doin'?

[@marshallpyatt5425]

I am enjoying your other videos, but then I saw this one. My friend has 2 Centaur Machines. I have sent him a link to this video. Thank you.

[@retrobeastgames]

I remember this table, love pinball machines. Great video Clive :o)

[@sparkyprojects]

That old board, you're right, bucket brigade delay line There's a single chip echo unit around now, the PT2399, there's a few ready built devices on Amazon, the one i have works very well.

[@bigclivedotcom]

I did consider redesigning it around the PT2399, but it actually has a high support component count.

[@seannot-telling9806]

Not sure if you have/had Radio Shack. Most here are worthless for any real electronics now. But they had a IC out that was at the time very spendy and later came up with a kit. Here is the data sheet. www.pmerecords.com/Docs/Archer_SAD-1024_Tech_Data.pdf

[@gordonlawrence4749]

Sean Not-telling we certainly had Radio Shack / Tandy in the 80's. I worked for a company that used the TRS-80 for automated test equipment. At some point about 15 years ago possibly they ceased to be in the UK. Pity because the TRS-80 was damn good for it's day.

[@userPrehistoricman]

Unfortunately for the PT2399, you can't get sub-30ms delays. With this Holtech chip, you can just swap out the RAM to be smaller for a smaller delay.

[@4E414D45h]

I like PT2399 very much

[@Snolferd]

This is probably one of my favourite bigclive videos, I love pinball machines.

[@srebrenitarantula9470]

Centaur is the best pin ball of al ages

[@groovejet33]

Your one clever man Clive. I had no idea you were that good. To design your own card, great

[@EVguru]

I built a discrete chip digital delay line echo/reverb/phaser/flanger board many years ago. VCO, 555 timer, binary counter, Audio compressor, ADC, ram chip, DAC, Audio expander.

[@kensmith5694]

A useful thing to know about PCB layouts is that the gerber plot output from many PCB packages can be read by Kicad and with a bit of work turned back into a PCB layout.

[@alexmarshall4331]

Clever bear...can you imagine a guided tour of BC's Manx domain...Willy Wonka meets 90s RS catalogue in Poundland and beyond...don't care that it goes over my head really enjoy the videos 🐻

[@TupmaniaTurning]

Awesome! You certainly know what you’re doing! 👍🏻

[@twocvbloke]

It's always good knowing you've brought something back to life that could have gone the way of the dodo due to iffy designs and obsolete parts... :)

[@juststeve5542]

Could you remind me of this later as I continue day two of rebuilding carbs! ;-)

[@twocvbloke]

Day two? Pff, I've taken much longer than that, but succeeded in the end, and felt good about it despite the frustrations and annoyances involved... :P

[@surfinmuso37]

It's funny - I understand very little, yet I can't stop watching.

[@LakeNipissing]

Excellent video, Clive!! I like how in the Centaur, the games options are done with dip switches. In the 1977 Argosy EM machine I have, it is banana plug jumpers! And the sounds are solenoids striking a mini xylophone. Huge leap in technology in just a few years in the early 1980s. Unfortunately the reliability of "solid state" LSI components wasn't all that great yet.

[@bigclivedotcom]

One of my older electronic pinballs (Bally Xenon) still has an option to emulate chimes instead of the more modern sounds. Which is odd because it also speaks.

[@LakeNipissing]

Watch for a package in the next week or two... I sent you a KZbin PM to let you know, but that system is dubious at the best of times.

[@LakeNipissing]

Kind of the best way to describe them, with a row of sockets with a plug on the end of a short wire to select points needed for extra balls, 3 or 5 balls for a quarter, etc. The connectors used to interface the back glass lighting and score panel with the main electronics under the playfield are pretty primitive looking too.

[@glenngoodale1709]

This has got to be one of your best videos !! Love to see how old things work ....

[@teacfan1080]

Man, I played that game so often "back in the day", what fun! Yours sounds like it's in pristine condition. Loved all the backglass artwork.

[@964tractorboy]

A great machine and video. Thanks.

[@mjrdainbramage]

Clever and generous! Two of the many reasons I love your content Clive.

[@raleighsexton7734]

Much more sophisticated than my old Williams machines! Still love to play them though. Solar Fire and Laser Cue.

[@harryjnr2335]

My dad worked for a machine operater in the 70s and 80s, this game was/is awesome. Would love to see under the playing bed again Clive. 👍

[@Axl_Pose]

Christsakes! your vids usually help me sleep (not boring, your voice is very relaxing). I shat the bed when the machine decided to "play itself"

[@cogidubnus1953]

I love old-time pinball machines, (this one is probably a tad too modern for me!), and I'm delighted to see you share this interest...and moreover actually own an example...kudos mate!

[@onecreativecriminal]

The first pinball machine I played when I was a young

[@jameslucas6589]

Very nice work. It makes me reckon how just like the skill of heart transplant surgery, it is fairly simple once you understand how. That said, I do not have a clue how either is done. Your skills are amazing. You sound great, you do great work. Kudos!!!

[@TheWibob1234]

First time i have seen this guy fully on video. With the accent he looks and sounds like a viking.

[@andiyladdie3188]

Maaan! that machine sound is impressive, outstanding job Big CLive!!!!!

[@jakublulek3261]

Fascinating. I am more into old arcade machines (I used to service them for Capcom USA) but this is still very fascinating.

[@MichaOstrowski]

oh shit... I love this kinda old pinball shit... and you've actually went and fixed it :) you're the greatest :)

[@jamesm90]

Really nice to see a working Centaur, I had the chance to buy one about 20 years ago but bought a Gorgar (the first talker) instead, that wasn't a good move. More Pinball videos please Clive!

[@robj7481]

That's neat what you did. I used to repair pinball machines, including the Bally MPUs and the WMS system 8-12 and WPC. I remember the say it again board. I always loved Centaur for that. Bally had some great games, like Xenon, but ultimately, Bally lost out to WMS because Williams had faster action due to things like their highly responsive "jet bumpers"

[@bigclivedotcom]

I have a Xenon in storage. It speaks French.

[@bdogmccool8096]

I've got a centaur 2 and miraculously the speak again board still works.

[@Talon75407]

Friend of mine has one of these boards from Marco. Great job!! But you already knew I like pinball.

[@noakeswalker]

Nice echo replacement pcb. It's obviously quite popular in pinball circles BC. The displays in this era of Bally machines (others too ?) I now realise are most likely Panaplex - (7-segment version of a nixie for anyone who didn't know) - thanks to Fran Blanche for bringing the fabulous Panaplex display to my attention, after all these years in the dark :o)

[@BPantherPink]

WOW... Great work done then, Clive. Nice of you to have given away the design too. Luvya.

[@Lyndalewinder]

Great video Clive - very interesting and so much better than teardown of crappy Ebay LEDs, keep it coming!

[@GregMcCarthyUK]

Great video. Seriously old school electronics. Can probably replace all of those with a few chips now

[@Centar1964]

I used to repair pinball games back in the early 80's, and this by far was my favorite one...but could never keep that echo circuit working...replaced the echo board a couple times and then gave up....we deployed the game with no echo...

[@SuperFredAZ]

I believe, the original delay circuit was called a "bucket brigade". It is a combination analog switch and shift register. The signal was sampled as an analog signal, then shifted to another device, preserving analog level, after the signal was shifted desired number of times, the analog signal sample was placed on a low pass filter. The signal was essentially the same as it went in, but delayed by the number of shifter register states and the shift clock. The analog signal is passed along from register to register as a bucket in a fire bucket brigade.

[@RonLaws]

Oh god, I visited my nearby Maplin just yesterday to see what they had on sale, so depressing as Maplin was always a big part of my life growing up, that is the last time I will set foot in one. Sad times :'(

[@thatcreepylaugh]

Went in a local one for their Closing-Down Sale. Quite nostalgic to go in and find overpriced stuff (even with 50% off) & nothing I actually want; being disappointed by Maplin's one last time.

[@moss1transcendant]

Your very clever Clive, thankyou for sharing your interesting facts. I enjoy the topics alot .

[@davidf2281]

Three minutes in and I can't watch any more for fear Clive is going to knock that glass off the top of the machine.

[@MrHack4never]

He doesn't break anything in this video

[@tracyscott3261]

Or it slides down the top of the play field. But I had faith he knew what he was doing. Really neat video.

[@visionlightlab6094]

Terrified me also!

[@90vanman]

Back in 1970, in East Ham, London, was a small firm who made a fortune screen printing the glass panels for pinball machines and other display stuff for big retail outlets. I worked in the same building and was fascinated by the intricacy of their work. As you say, the panels are as rare as rocking horse poop and very expensive.

[@bigclivedotcom]

A modern replacement is translites. Colour printed vinyl sandwiched between two sheets of glass.

[@RoscoeTEHClam]

As a bigclive fan and pinball fan, this is the perfect youtube video

[@WilsonBradleyTheOfficial]

Love Centaur... Once of my favorite Tables in VR

[@whoopjohn]

I never got my Centaur's 'Say it again' board to work. Centaur is a great game.

[@0youwannagethigh0]

aHOW COOL is that machine??! Awesome Clive!

[@mUbase]

Thats a lovely design Clive. xxx . I like your "chunky trax" PCB layout.

[@DHzLot3]

I’ve drank many a beer playing Centaur. Wonderful game, great overview.

[@Xplasma1]

"If I broke this back glass it would be very bad news, as it's worth more to me then my kidney was at the time. Goodbye little kidney!" Seriously, awesome video and for a twenty year old design your board looks like it held up quite well.

[@JerryEricsson]

Ah yes, take me back home once again! Back in the 80's I was the Chief of Police for a small town in the oil Patch of North Dakota, when the black gold was flowing freely, before the State shut it down with taxes. Everything was growing, and even the arcade's were becoming a huge money maker with the roughnecks needing more to do then get drunk and be somebody. I had a buddy who worked at the State Scale weighing trucks as they came into the State, his father-in-law, a real cool old fart owned the arcade machine repair and service center, as well as the majority of the machines in that part of the state. He had a small shop just a half block from the back door of our PD, and on slow days my assistant and I would wonder over to his shop and "try out" the machines he was done servicing. I will never forget being insulted by that damn machine, I nearly put a .45 round through the front glass, I was so pissed, the worker who was tweaking another machine nearly fell off his stool laughing, as did my assistant. Ah those were fun times!

[@carlbarlow6942]

Very Cool Clive! I had a Memory Man delay for guitar that used the same SAD components with the variable delay and feedback controls, it was fun but noisy! When those flat neon displays started appearing in the pinball machines we all wanted to play them.

[@TheMB2333]

Nothing like throwin' back a few beers on a Saturday evening and watching the big fella' tear down a pinball machine.

[@jlucasound]

Your design is awesome. I find it, Highly Compelling. ;-)

[@AlFooteIII]

You made your own echo board? You're a pinball wizard!

[@tonyambrose5679]

Nice work. I have a Centaur machine and it still has the original Say It Again board that still works very well. I do worry about it eventually dying though so maybe I'll pick up one of these to have as a spare. Thanks.

[@MrRoan00]

Lovely! Please do more pinball related videos! I grew up playing around in my parents arcade repair shop as a kid, testing out all diffrent machines :)

[@AttilaAsztalos]

I definitely appreciate all the old-school tech involved in the echo card and how much more period-appropriate the Holtek replacement is compared to a modern solution, but to be honest for a generic application these days I'd probably just reach for the first DSP-capable MCU I can find that I might have a programmer for, load the "echo" example and call it a day...

[@GiddeonFox]

I love videos like this, about how the electronics for doing things that we'd consider incredibly simple these days used to be very specialized and state of the art. You mentioned something about doing echo with multiple tape heads and a tape loop, that sounds super fascinating and I'd love to see a video about that if you can find one for a reasonable price :)

[@CentiZen]

Oh man, being a massive fan of you, and a hobbyist pinball restorer, I smashed my mouse so hard to click on this video there is a hole in my desk I guess I shouldn't be surprised - between you, Ben and Jeri, it just seems like something electronics nerds gravitate to.

[@retrobeastgames]

The voices on this table, reminds me of Sinistar the arcade game, from the 80's.

[@MrStabby19812]

Retro Beast Games was thinking the same. " I am Sinistar!," "Run! Run! Run!," "Beware, coward!", "I hunger!," "Ron Howard"

[@retrobeastgames]

It was a cracking game Sinistar

[@Slider2732]

LMAO "Ron Howard". Reminds of the JFK conspiracy in Berzerk 'Got the humanoid, got the Zapruder'

[@TinySpongey]

"Beware I live"

[@amojak]

Hey Retro, here is a track that was created to honour Sinistar!! > kzbin.info/www/bejne/h4aQoISLfZympc0 :)

[@ArmadaAsesino]

New Big Clive video! I don't care what it is, but I have to watch it immediately. Probably my favourite KZbinr

[@braeburnhilliard8340]

Wow, pinball was always one of my favorite games!