Hi he was sayin yeah, what are we doing today? Save you the - I do wanna look cool look at this. This is my original kit from when I was about your age Sagan how old are you seven? seven? Awesome! This is the Tandy / A RadioShack Science Fair 201 Electronic Project kit and this is my original one I actually had as a kid. This is for those who want to know. this is how I learned electronics or you know I started out learning electronics.

wasn't actually this one. did you know that I had the 50 in one first. Yeah I did. but I don't have that anymore.

There was the 50 and one was the first electronics kid I ever got I was probably like 5 or something and then I have the hundred and fifty and one and then the 200. he won but only the 201 remains. It's a bit teddy, it still works and how does it work? So yeah, why is. Why is we've got spring terminals? Yeah and we hook up all of the individual components.

We're gonna have fun! So we're gonna build up some a couple of projects from this yet. and I think we're gonna have to strip some wire. So we got some wire. Yep.

Wire stripper. Alright, okay so you can show us how to strip the wire. So first see the tiny hole there. those tiny little gritted holes There you don't split, you just find the size hole that you you think you need.

Put the wire in that hole and out there. And then there we go. We stripped it well done and now give it a little twist on the end so that yes I just hold it in your fingers and give it a little twist like that. Alright so you're gonna tell us about all the individual components on here.

you go for it. So so when this one 240 section here where we've got the resistors, those little things, they're got the resistance. and and on the 41 to 44 we've got. yeah I call them Dodi's Dodi's days.

I Used to call them Diode. Ease that their diodes are back. Yeah yeah. God And then in the input transformer here in the orange section, then the output transformer in the other orange section, and of course the batteries in the green section.

And of course you need antenna antenna right? Yeah, so you build radios and stuff and tenor rod the transistors in the other pink section here. What are these little brown things? They look good because capacities in this other brain section and capacitors they come into? Well we hear two different types. we've got the brown ceramic ones and the blue electrolytic ones. I Hope they still work after all these years.

Yeah, fingers crossed. Well we go. Then down this bottom bit here we've got the turning orange bit, then the control orange bit the meets our blue bit the LED digital display like emitting Diode sorry this the Select it's a switch. Yeah so let's switch and we've got the key.

yeah which is just a physical like plastic. Okay, it's like a mosque. Okay, you just push down on it. Yeah and then we've got the lamp which is probably just down and then we've got the SDS CVS sell CBS sell.

That's it. That's a really difficult thing to say. that's a cadmium sulphide photocell so that's a light detector. it's just a text line.

and then we've gotten the speaker down there, you speak adjuster. and of course we've got T1 and T through the terminals. and these not the original lids on daddy actually they actually had little surface mount ones actually a right recess into there and I don't know I Used them for some project and I replaced them with just standard LEDs in there so that I had from my jump in. So there's our seven segment display we're gonna control which has a switch on it.

nice meter look at that. Did we say the integrated circuits? Oh we forgot the integrated circuits. Which ones are we got? We've got the integrated circuit quad 2-input band and the integrated chocolate your JK flip-flop. Yeah Now the really good part about this of course is the not only like the spring terminals which made it easy to I do it but the book the comprehensive book that it come to the come with me to the world of nor gates flip-flops transistors and lids.

haha Trust me for a like it's like a seven-year-old Sagan's age back in the well I won't say when but back in the early days before the internet and before all the other distractions and gizmos, this is what the curious kids played with. It was really cool. Anyway, we have 200 different projects see and then it starts by identifying all the components there and then all about troubleshooting as well building projects, Getting started keeping a notebook and encouraged you to keep a notebook which I did don't know where it is now back in the day and yeah it's very cool and looks like well with all the terminals that then I showed you tells you there's a big change coming because first of all it just makes you build them up by route basically just like visually like that. And of course you know you don't get to learn about schematics, circuit diagrams do you sayin? No! But now turn the page.

Yeah we can start learning about circuit diagrams and they get more and more complicated. Multiple counter by 200. Wait right there. 199, 200, 300 and then explain that Courage's you to explore electronics on your own.

Fantastic! So which one are we going to build? Say yes. Well we're going to start off very easy on the rain detector number four. so we're gonna do it visually. First are we, even though you didn't you know about circuit diagrams, don't you? Yeah, here it is.

rain detector. That's the one you wanted to build. Yeah, All right. So that looks pretty simple.

if there's not much in there we're using now. Output Transformer Yep, we're using some capacitors, some resistors, and what are we? What else are using in here? Say him. We've got transistors, transistors and we've got a switch and and the speaker. So I think it's going to generate a time.

What do you think it will detect rain? But there's no rain outside today, so no rainfall coughs. Oh, so we're gonna get a jug of water instead. Cool. And what do we have over here just in case, just in case anything fails.

we've got the vales and the essays that I throw it out before. Oh, let's do it Okay, Say yeah, lets water it up. Okay, so guaranteed A Wyoming Secrets. Oh, you're gonna fall in the wiring sequence.

Oh I Thought you'd just follow the visual. but yes, it does actually have a wiring sequence if you want to actually do it in order. but you don't have to do it in order so you can just. But it was easy for sure when I found that visually you would end up missing a few if you did it visually.

So I think in the they learned the wiring sequences was a guaranteed way to get it. You know, working and then you wouldn't have to troubleshoot it. But as I've said before, the best way to learn electronics is to fail and troubleshoot it. So hopefully it doesn't work.

Sagen, troubleshoot it. Yeah, actually. I think that's already this. Yeah, it's pretty simple.

just follow it visually. So 24 to long 1 to T 1 so we're gonna bend that back. twist it. Yeah, the ones actually that we'd got with the kit.

they actually came pre-tin The wires were pretend on the end. That was handy. so the stranded wires are bit. yeah knowing knowing that we made because Danny lost a lot I lost all the wires didn't I almost all of them.

There's still some left. Yeah, these white ones and these black ones. Now we're doing the center tap of the transformer. Yeah, We? yeah, that's called the center tap.

that's the negative term. Oh, you got two wires in the same terminal? Now you can get a bit tricky. You gotta make sure one doesn't fall out. Center Tap of the transformer? Cool.

I got it. You got it all right. So we're connecting our speaker to the output if the output transformer. Yeah, the second that's called the secondary side.

sorry, let's the other wire of the speaker. That was a bit going. Danny Okay, oh that's gone. That's head that's dies.

That's had better days hasn't it? Yep, Oops, Well it's It is many decades old. So many decades and I'm sure was used in to build hundreds and use hundred the times to build up circuits. You've got a circuit building kit at home as well. Don't you say it doesn't use spring terminals? uses like being tabs and thingies and snap taps? snap - but but still as like the same components.

Yeah, and and what kind of gates do you know about the Or gate and and gate? Yeah. can up a transistor? Now stay and that's the emitter. See the little ego? Yeah, yeah, that's the emitter of the transistor. But we can't see that because we don't really have a circuit diagram to work from because we're going visually are we? so? But when we have a circuit diagram, you'd be able to see it.

Why did you just hook up there? So yeah, competitor and a transistor. Cool. We connected the base to a capacitor here. I Think we're building an oscillator.

Sagen I Got two capacitors in this circuit and it looks like and this capacitor goes back to the collector of the transistor. Okay, now the short wire. We have no more light cool and our collector of our transistor goes over to drive the transformer over here. so it drives the primary side of the transformer.

It's called double contacts. A Tricky: I Always had lots of problems with double contacts. I'm not working well. It was driving the driving the low side of the primary of that transformer there.

Oops. I Thought that was an NPN transistor. It's not. It's PNP See the arrow going.

It's a PNP transistor. NPN So that's why It's on the battery. The positive of the battery goes over to our switch and then our switch goes to the emitter of the transistor which is a high side transistor which drives the transformer. Cool! Now the trick I found with the double ones is not to put it on the same side because it it always come out.

You stick it in the other side so that this one couldn't fall out. So that's a little trick I Learned Okay, we haven't finished building the base of our transistor there so that's going to go up to the resistors. So I Remember, put it on the other side B symbol there Terrific! One more terminal of our transformer Saiga which is not hooked up. that's the high side of the primary.

the transformer. where does that go? I think I need a bigger one I don't think I Always found that the kid actually had pretty like it. came with all different sizes that are all color-coded and you always had enough. You weren't left wanting from memory and then you lost a lot I lost a lot of wires but then we cut off the right sizes.

again. All right. I Think we might be close to done. So yeah okay I know press to easy.

Zoom what's easy Of course used batteries and I never knew this at the time. but of course we've got TTL transistors of course 7/4 series and you know they though parenting from you know over six files directly from the batteries. There's no protection or anything from this. Let's go find some I Believe division of Tandy corporation Fort Worth Texas and I Thought it would be really cool to use my first multimeter.

This is the Micro No 22 201 you'd to joules 20k ohms per volt. Thank you very much. This is what I used with this actual kit when I was a kid. So I saved up my pocket money and this was my first multimeter and it still works.

Unfortunately, it uses the two millimeter probes I don't have any, but I do have original Micron Tur probes here, but their standard four millimeter banana terminal so they don't work. But the good thing is Sagan Look at this trick right? They actually go in backwards like that so we can use them like that and then do this. Let's measure some batteries. Yeah, fans only need six out to twelve.

We don't actually have any new ones around when we run up, so we put this on DC volts. Yeah, yeah, so we go around here. It's got five DC volts. Yeah.

so when the meter goes all the way to the end, it's five. You see how it's got from zero to five on that black scale? Yeah, DC Okay, what voltage do we want? About one and a half? So you want it to go to one and a half? Yeah, it's good. Sorry, might be too much over one and a half. Yeah, Okay, so let's try it.

Okay, let's measure one because these are running and you've got. Yep, yeah, you got the polarity correct. Let's go. Oh Yep, that is one and a half volts.

That's it. Ah, that's a good one. Winner winner chicken dinner. Yeah, that's a winner winner.

Okay, let's look at this guy. Oh nothing. It's just dodgy contact. Try and press harder.

There you go. That's good. Yeah, my fault. I Have thoughts: Try this circle.

one well backwards. Oh sorry. That's all right. I I Can never remember.

Yep, that's one volts as well. You see how I could get a deke contact. then it sort of the needle. Wiggles And what you've got to do cuz it's not a mirror on it.

You see how if I tilt that, you can actually see two different and you can see the needle and the mirror image of the needle. Yeah, you've got to tilt it so that they line up like that. That's called parallax error. You want to avoid that to get the most accurate reading possible on your analog meter.

Yeah, that one's not quite. That's not too great. That's about 1.2 volts. Okay, wait a minute.

and of course we can test them Sagan A different way, can't we? We can test them by. Let's take this good one. Can we drop it? And if it goes thud like that and doesn't bounce then it's good. We already measured that one.

this one here. we just measured as dud. Yeah, well. it was one point two ounces.

I'm what about this while we're having legless? It bounced. Do it again. Yeah, yeah, it bounced. Said that one will probably fine.

Try it. Well probably fine is not 1.5 will probably find it's a 1.2 or 1.3 No no, no, it's 1.5 Why did it bounced? That's interesting. I think he better do a teardown. Yeah, that's why it's not bouncing.

That's an extra heavy duty. It's not an alkaline. It's got different chemistry inside. So oops, that doesn't work.

But that one measures good doesn't it? Yeah, So good. All right. Lucky Lost battery. You will win after they go test.

Olli I was to see how they are. It's going to the 25 volts scale. The scales weren't great on this. Let's have a look.

where's Al fondo on the back terminal there and it is. So we're on 25 volt range and it's over on 5 volts. Yeah, so we're good to go ready. Oh Actually put it down.

We'll turn it down to 5 volt range. 5 volts. Oh, we're actually 4 and a half. Yeah, we go.

That'll still work. Still very good to go. That's interesting. This is four and a half folks on there.

Do they actually have a diet diet protection in there? I Don't remember. We're gonna have to take this apart afterwards. What do you think? So yeah? Ted But of course we gotta put. okay.

so yeah. Beautiful. Alright, let's switch it on. Say yes.

yeah. so we've got our controller. Oh, it's already on. there.

we go. so switch it on, but it's not gonna make a sound wah. I'm trying to do our rain detector. Maybe my fingers aren't good enough? I Think we might have to.

Can you get a wire and just short out those two there first? Go. That's a bit disappointing though. It means we don't have to troubleshoot anything. but let's put it in some water.

Do you think it's gonna work with the water noise? You might have to troubleshoot it? Well, those terminals in the water. Yep. stick both terminals in there. That's interesting.

It's in the water. Yeah. what? So the water has enough resistant, one low enough resistance, and it tells you in here somewhere there you go. If you want to read the blurb about that particular circuit, it teaches you about that.

water is conductive. Sounds like somebody practicing to whistle and what if you separate them if you're stuck them out of what far apart? Try it. hold them far apart and then bring them together slowly and see at what distance it changes. You hear that yeah, changes frequency.

and when they touch sheet of and what it touches each other, see that what's going on when you touch each other. Linda What The teeth? Yeah, but it's gone. it's gone lower volume. so I'm catching them.

It was laughing before. So what's going on? and now it's not working. And though when I touch the tube wires they feel they're always touching the water, it's gone silent. Something's happening to our circuit.

Oh no. troubleshoot. Finally. this is what we hope for.

I troubleshoot. What's our first troubleshooting step. Sagan: measure the battery, measure the batteries. Yep, we're good.

We're good. We go just cold. try again. try to see it's really low in volume.

So just check all our wiring because with a physical build like this, a physical circuit build often. But why I could have come loose but it's still oscillating cuz it's still making a noise. Yeah, well when they're not touching each other in the oh there we go. oh say again.

I think I found it. Look, this is one of the original wires and I reckon it's got a Dicky contact. so do we have another one? Okay, well what we can do? maybe as we can join two new one so you want to put that on there and I'll put this on here and we can join them together. We can actually put them into a terminal like this.

It's called a float internal. Okay, so let's just put it in there. It doesn't matter, it won't hurt our chip because nothing else is connected. Now let's do it again.

Try it, Try the circuit again. and now put them right to the side. Yeah, it doesn't work. moving slowly closer together.

Very bad signal right? Oh, when they cut and the warna hug do I get any your touch them cool. We didn't say yeah. well done mate. That was awesome work and we got a little fold in there as well that was an old Dickey Contact Boys I'm Denny Since we forget that, that means we can add that into the book those two wise into the book.

we could just like and still walk Ethan It did still work. Yeah, but it doesn't. That actually doesn't change your schematic. So if you have one like a schematic on other pages like this, it wouldn't It wouldn't actually change, but it'll change your wiring diagram because you have different numbers, but the electrical schematic would remain the same.

So cool was that fun second. Yeah, I've only just say part 210 air time. Let's do it. Say it.

tear down. So can you undo these screen look and screw there. screw there there challenge yeah hi sorry Oh I'll join you. Let's go.

these are really too tight man. I We will put it back together because is a great Peterson it it is a great kid isn't it? Yeah, you can I don't you can't buy this exact I don't think you buy this exact one. You can buy similar ones but it's still called 201 but there's other companies that make them now. and I remember tearing this down as a kid and of course, okay, is that? Yep.

Hey, you lift it up. well actually grab the transformer there. no careful, all because we've got some There we go and even more lies underneath. Yeah, they all go to the front panel.

it's a little bit. how are you doing Wow Look at that picture. the ETS tear down. Pretty easy.

tear down and not much. It's just a battery box and uh, and thousands of wires. Yeah, that's about all it is, isn't it? I don't we? We'd sticking up to see that the IC is on its own little circuit board down in there and I'm It's all cardboard. It is cardboard.

Is that amazing. It's just cardboard. Yeah, that's all it is. Yes, cheap construction, but it works wonders and it's held up for all these decades.

It still works. It's a great feeling. Yeah, how does the 201 Science Fair electronic kit from the late 70s and early 80s? Is that a thumbs up? or a thumbs down? Double pop up? Actually. I'll do it for 10 1, 2, 3, 4, 5, 6, 7, 8, 9.

And what do we say at the end of the video I say you catch you next time.