CRT TV Music Visualisation MOD - Crude Oscilloscope Beam Dances To Audio

[00:00:00]Hello and welcome. Now today's going to be an interesting one [music] because I kind of don't know what I'm doing yet.

[00:00:06]I kind of do, >> [clears throat] >> if you know what I mean. So, I'm going to mess around with a CRT, yes risky, CRT TV, an old one which I got from car boot sale, and turn it into a visualization. Tinkering with an oscilloscope back there and repairing it and the end seeing the final result. So, that gave [music] me a taste for, you know, I want to create a visualization.

[00:00:40]>> [music] >> Also because this past few weeks I've been messing around with the Amiga and the genlock, and you know, [music] the camcorders and CRT camcorders. So, this, yeah, and I've been trying to create more footage and more interesting visualization for my music [music] videos. And because I just love messing around with analog video and yeah, analog visualization.

[00:01:17]So, yeah, that's going to be the that's the phase I'm going through this summer. So, yeah, let's let's go with it.

[00:01:26]Because the first things first, I'm going to open up this CRT.

[00:01:31]Because this is where It's a CRT digital clock radio which I literally got from the car boot sale for like £5.

[00:01:44]The pads which I remember, oh my goodness. It's like these things, I mean, they're not the most ergonomic comfortable things, but I don't know, I kind of prefer I always preferred the Sega over Nintendo. You know, sorry Nintendo fans, but I I was a Sega girl.

[00:01:59]>> [laughter] >> Yes. Oh my god, it's there.

[00:02:08]Look, it's actually quite playable on this diddly screen.

[00:02:15]Got to play this thing.

[00:02:22]I'm going to turn it into something that I'm going to actually use.

[00:02:30]Okay, so I've just disconnected this bit here, which is the alarm alarm clock circuitry. [music] To be honest, this is quite simple, although please be careful. I'm going to discharge this right now because it still is a CRT even though it only operates at 12 volts.

[00:02:45]It's 12-V input there. All right, so I don't need this to operate at 240 volts.

[00:02:50]So I'm going to actually remove this. Now, even though it operates at only 12 volts, this thing here, which is the line output transformer or flyback, you know, transformer, this takes the voltage and increases it all the way up to, >> [music] >> I'd say, 10 kilovolts, ish.

[00:03:09]And that is what, you know, powers the CRT and makes it actually light up. The only thing I need access to, I don't need to mess around with that circuitry. The only thing I need access to [music] here is actually the yoke, which is this um here, the actual coils wire here, which [music] guide the beam until it where to go, you know, so it creates creates the image on the screen. Okay, first things first, I need to discharge this.

[00:03:34]Okay, so that I'm going to connect to ground and touch that screwdriver onto the electrode.

[00:03:46]It didn't arc, so it wasn't charged.

[00:03:50]Okay, don't know what that is. Might some soot from here.

[00:03:58]Okay, that's easily removed.

[00:04:03]Fantastic.

[00:04:04]Don't need the mains that I brought here anymore.

[00:04:10]Very dusty in there.

[00:04:27]>> [music] [music] >> Okay, so I mean it works, but unfortunately only with mains >> [music] >> and not with the 12-V bench power supply. Why I don't know, maybe the connection is loose, but at least the thing itself works.

[00:05:09]Here we go.

[00:05:11]You heard that.

[00:05:13]The tubes need discharging. Cuz that could really do some damage.

[00:05:20]Okay, honestly, I've no experience of going inside a CRT and performing this kind of a >> [music] >> mod on it. Something I do very carefully, but I think I've been uh looking in the wrong place. Yeah. I'm trying to look for the access to the yoke X axis and Y axis, and I've been thinking it's these, but it actually isn't.

[00:05:42]Now, the closest thing to this what I've done, what I'm trying to do now is uh those small magic eye tubes they used to use uh for, you know, indicating before, but now I've done a project like this. It's probably is before I went on YouTube. I did it in 2012. So, everything was accessed on those tubes. There's no There wasn't any yoke like this. This is the yoke.

[00:06:07]The access was uh via this, and this looks familiar to me. So, my mind went straight to this end of it.

[00:06:18]>> [music] [music] >> Like that. So, okay, the access to the yoke is probably going to be from here.

[00:06:34]It's not, right?

[00:06:37]There's two coils.

[00:06:38]So, these The access to these actually is not there, but here. Cuz it's these four wires. They're going underneath here, underneath the tube, and they're clipping into the board there. Right, okay. So, I've unplugged the yoke here.

[00:06:58]The yoke is the part which creates the shape of the image. So, it's like an electromagnet on I'll explain this a bit better later on. I'm just kind of excited to get into this uh at the moment.

[00:07:09]Okay, so here I have my signal generator or function generator, waveform generator, whatever you call it.

[00:07:15]Channel two channels, right? Channel one [music] and channel two. So, you can send two separate waveforms. Okay, so the first two, the red and the blue on this yoke are one of the axes.

[00:07:30]Right? So, they they're a pair.

[00:07:32]And the second one, the gray one and the yellow one, are another axis. Channel two, let's connect it to the yellow and the gray.

[00:07:43]Channel one it's connected to the blue and the red.

[00:07:49]Okay, so I've set channel one 10 hertz 5 volts.

[00:07:56]And exactly the same channel two, right?

[00:07:59]And they're both turned off. So once I turn that on, it should appear as a dot in the center.

[00:08:09]Okay, plug that in.

[00:08:11]The CRT warm up.

[00:08:13]Let's turn on channel one.

[00:08:17]Here we go.

[00:08:18]It's going side to side.

[00:08:20]Turn on channel two.

[00:08:24]Channel two's reacting more than channel one. I need to test the impedance of the coils here, right? Because I'm putting this all the way up to 12 volts peak to peak.

[00:08:38]So at least they're reacting. Okay, so the impedance of one of the coils is different from the other one.

[00:08:45]The yellow and the gray 9.5 ohms and the red and the blue 9.5.

[00:08:53]That's quite a difference.

[00:08:55]Okay, so the red blue pair is um X axis.

[00:09:00]And it requires quite a bit of voltage to kind of I think I'm having too much fun with this just messing around. So when you increase the frequency on the um X axis, the horizontal.

[00:09:14]50 hertz. Okay, so it's 100 hertz vertically, right? Triangle wave. So horizontal is um sine wave 50 hertz. Now if I were to increase that to 100 and match it it creates an oval.

[00:09:32]This is starting to get into Vectrex territory now.

[00:09:35]Okay, you can see I'm going to have a lot of fun with this.

[00:09:38]>> [laughter] >> I'm building a TDA 2822M amplifier for this.

[00:09:49]Okay, so next morning and I've been building an amplifier circuit to use with the yoke.

[00:09:57]Uh to put the signal through that and then yoke, I think hopefully it'll be good for impedance matching.

[00:10:03]Uh basically the amplifier I built is the um TDA 2822M amplifier, the same one which I built for the SID boombox.

[00:10:15]If you remember that.

[00:10:17]Some of you will remember that uh series. It's probably the biggest series on my channel ever with like 22 parts or something like this, probably more.

[00:10:25]And uh yeah, it was the biggest project I've done. So, here is the amplifier.

[00:10:30]You know, it's worth [music] giving this a go first. I don't even know if this is the the right amplifier to use with a yoke. By the way, off camera, I actually extended the wires of the yoke. This is the X axis, Y axis. So, I don't have to keep putting my hand too close to there. Okay, so the blue one directly here at the bottom, that is the output directly from the function generator, so the input of this. So, these two are the both the output channels of the TDA 2822M. Okay, so the amplifier is working. The blue one is 1 V.

[00:11:09]The output of it on each channel is 1 2 actually 3 V. Now, let's see how Now, let's see how this works out when we connect it to the actual yoke itself.

[00:11:20]Okay, disclaimer, right? I'm doing this for educational purposes. This is not a tutorial. I don't want anyone out there hurting themselves messing around with the CRT, right? You got to know what you're doing. So, I don't recommend messing around with a CRT. [music] So, 1 V peak-to-peak barely does anything.

[00:11:40]Oh, okay. There's more happening on here.

[00:11:43]So, it's the impedance.

[00:11:45]Okay, that TDA chip is getting really hot.

[00:11:49]I mean, it's creating an interesting shape on there.

[00:11:58]It's sort of like that, but it's on the Y and the X axis, but this is obviously not accurate representation of the wave.

[00:12:06]I know that. Yeah, but it's just the fact that I want any sort of visual visualization, and I want something some sort of abstract shape to dance to the music. I'm not This is not for accuracy at all. Thing is, I've always loved visualization of any sort. I mean, the first starting with the VU meters, you know, things like plasma globes and lava lamps, optic fiber lamps, and you know, all sorts of things like this. I've always been into them. I'm a very visual person. And this is just my kind of thing, especially if it's analog. Analog just feels more organic.

[00:12:39]Something about it, something special about it.

[00:12:43]I am a TV.

[00:12:45]Okay, so I'm here this beautiful hot summer evening surrounded by amplifier circuits, trying to get my head around which one to actually use with this. Now, the yoke, imagine it to be like you know, a speaker, right? It's just a coil of wire. Now, whatever that speaker is doing whatever the coil of wire is driving. In this case, it's driving a cone to actually produce sound. Now, that uh yoke there, that is working in the same way as a speaker.

[00:13:19]Except that's not driving a cone. That is driving a beam to create an image. The concept basically is the same.

[00:13:28]It's the coil of wire is basically electromagnetism. [music] But the thing is with this, right?

[00:13:32]Almost put it back.

[00:13:34]This is Oh, 4 ohms. I thought it was 8 ohms. Okay. So, this is a 4 ohm speaker.

[00:13:40]Usually, you know, they're 8 ohms and 16 ohms. And if you've got those you know, high impedance headphones, it can be 32 ohms or might I don't know, maybe higher.

[00:13:51]Actually, yeah, higher. I think my Beyerdynamics are 100 and Just a minute.

[00:13:59]What?

[00:14:00]Ohmage. Ohmage. Ohmage. Impedance.

[00:14:06]>> [music] >> Okay, so these are my Sennheiser headphones which I've had for over 10 years now.

[00:14:11]I think way over 10 years.

[00:14:13]>> [music] >> And these are 40 ohms. They require a good amplifier to drive them.

[00:14:19]Impedance is complicated, but if you want to For those of you who don't know, if you want to explain the simple way, they require more more ohms to push through the resistance. It's a higher resistance impedance, AC resistance.

[00:14:35]Yeah.

[00:14:36]Putting it really crudely and simply.

[00:14:38]These are my more recent Beyerdynamic 990 Pro headphones. These are 250 ohm headphones, yeah. I use these for my studio work, mixing, mastering, you know, things like this, music creation.

[00:14:51]And these are yeah, they require a good amplifier to actually drive them. I've gone on a tangent, clearly.

[00:14:59]As I do, always.

[00:15:02]Now, in comparison, these poor little darlings are actually 4 ohms each, yeah?

[00:15:08]No, I'm not going to do this. I started going into like talking about impedance and headphones and speakers. We're not talking about that right now. We're talking about CRT deflection yokes, right? So, then, the vertical axis, the Y axis, right? That is 9.5 ohms. That's sort of normal. It probably feel like to an amplifier, an 8-ohm speaker, right?

[00:15:35]The X axis, the horizontal one, is 0.1 ohms. It's practically a short.

[00:15:43]Yeah? That's the thing. This is the one that's been causing the the problem.

[00:15:47]This is the one that when I used it used my um TDA TDA 2822M >> [music] >> circuit to drive it. And yes, I Let me show the one which I built. I'm more proud of that one, right? Because I rooted around some [laughter] my my electronics trying to look for amplifier circuit boards that were already built. And I found the 2822M, didn't I?

[00:16:16]But I built one already.

[00:16:18]So, yeah. Now, as far as I know, the output of the the circuit, the uh TDA 2822M, is 8 ohms. I'm not sure if it's six or something like this. So, the Y axis is fine, yeah? With this.

[00:16:36]The X axis, however, the one is 0.1 ohms. That makes this overheat, right?

[00:16:42]So, it's like a There's an impedance matching thing going on, you know, happening here. And that's what's been driving me nuts.

[00:16:51]So, what I did last night, I looked around for something the lowest um impedance amplifier. It turns out the class D amplifiers tend to be quite low impedance. Now, this class D amplifier here, it's able to drive 2-ohm speakers. That's the lowest I could find. Obviously, it's not every day that you're going to drive a CRT deflection yoke, yeah? With an amplifier, so they're not going to cater for that.

[00:17:19]Now, I don't know if putting a 2 ohm resistor in series with the yoke, you know, will protect the amplifier. I don't know what effect that will have on the image, if it will See, this is how I do electronics. I just mess around. I try different things, and I just end up getting a result, and then I just then I learn. I learn from it, yeah.

[00:17:42]That's how I do it. That's my way of learning everything in life. That's how I always have done it. I'm not conventional at all.

[00:17:50]Yeah.

[00:17:53]Okay, so I've got everything connected.

[00:17:56]The yoke X axis is left output, and Y axis is right output, right?

[00:18:04]So, I've got them connected, and power's connected, CRT on, and function generator up and running.

[00:18:15]Ooh. This is perfect.

[00:18:18]And it does more than Okay.

[00:18:22]I think this is the perfect amplifier for it. However, what I want to do, yes, it's low impedance, right?

[00:18:29]But it's driving 0.5 ohms when I think the lowest on its spec is 2 ohms.

[00:18:36]So, I'm going to just put a 2 ohm resistor on just to kind of take the just to make it easier on the poor thing, yeah.

[00:18:49]It has actually balanced it a bit. It It's made it appear more like a circle. Let's see if everything's right. No, it will be cuz there's an identical signal going into the left and right channel of this, right?

[00:19:03]>> [music] >> And if I were to balance the um the resistor, you know, the resistance, maybe it'll appear as a full circle.

[00:19:14]That'd be uh more accurate.

[00:19:17]That'd be way better.

[00:19:19]Let's try that.

[00:19:22]You just experiment, don't you? It's how you discover things.

[00:19:30]It's sort of changed its phase a bit.

[00:19:34]Maybe 10 is too much.

[00:19:37]You know what? I'm sticking to the 2.2 ohms on the output of the horizontal, yeah, on the x-axis, because I'm happy with that. I'm happy with the visualization. It's kind of like frontal.

[00:19:51]It looks like it's a square wave. It's not perfectly square. It looks funky. It looks like somebody going like that.

[00:19:58]>> [laughter] >> Honestly, the amplifier is perfect.

[00:20:03]Get yourself, if you're going to do it, if you're doing this. People have done this. This is nothing new, by the way.

[00:20:08]People have been doing this, you know, for years, yeah. [music] It's just me.

[00:20:11]I've got the CRT and I just thought, "Ooh, I want to mad scientist moment has reached goals."

[00:20:22]This one is a bit mad. I got an I got an extra one, cuz they're not they're not that expensive. It was like two for 10 pounds, something like this.

[00:20:30]And they're based on the PAM.

[00:20:34]I'll put an affiliate link in the description below. And the um first comment or something like this, yeah. To this.

[00:20:43]Because they're really good. Normally, I avoid costly amplifi- amplifiers. Yes, I know they're efficient, but they tend to have, because it's digital, some sort of digital conversion going on, or some sort of, you know, it tends to have a little noise and um I just like the old traditional class AB type, or A or AB type, like vintage. I mean, I'm not saying no to them because you know, a lot of things these days [music] have class D. [snorts] My Bluetooth speakers, I'm sure they have a class D. I'm sure lots of things have, you know. So, I'm not against them or anything. Okay, so I am back now and this time with my music player connected to this. And let's see how music looks on this.

[00:21:38]Wow.

[00:21:44]It responds to bass very well.

[00:21:47]>> [music] >> Don't forget, I'm going to do a separate volume controls for left and right, yeah?

[00:21:57]So, I can adjust the X and the Y axis.

[00:22:03]This is just like testing. Wow.

[00:22:16]This is interesting.

[00:22:23]The bass looks like coils. It's It's interesting.

[00:22:29]>> [music] >> This is so cool.

[00:22:47]>> [music] >> Wow, look at that.

[00:22:52]>> [music] >> It's almost symmetrical.

[00:22:56]Yeah, definitely what I want to do is adjust the um X and the Y axis on this and uh yeah.

[00:23:06]Wow, it looks like Spirograph almost sometimes. This is so cool.

[00:23:24]Oh, this is not I've got more that I want to going to do. This is not this is just the beginning of this. Yeah, right.

[00:23:32]And um the possibilities of a modular synth as well.

[00:23:35]Yes.

[00:23:40]Let's try a more [music] like let's try a chip tune. Yeah, like a C64 synth.

[00:23:49]Oh, that's funky.

[00:23:52]Do you know what it reminds me of?

[00:23:53]Do you know that Winamp um uh thingy visualization visualizer it kind of goes like that it's like in a circle and it does that. I don't know there's something like that it it brought Winamp into my memory.

[00:24:08]Wow.

[00:24:13]It's just This reacts better to um stereo because obviously it's left and right.

[00:24:46]My favorite bit of the track. Yeah, this bit. I love it.

[00:25:08]>> Okay, so there's a JavaScript oscilloscope uh thing. You can draw. Let me try and draw an M. Just something simple.

[00:25:22]No.

[00:25:23]It's because it's X and Y are the wrong way around.

[00:25:29]Let me swap the outputs.

[00:25:31]Where's the stupid screwdriver gone?

[00:25:34]It also depends on if the coils are the right way around as well.

[00:25:39]No?

[00:25:42]Plug in your oscilloscope's audio output into an oscilloscope right X axis, left Y. So, right is X, yeah. Okay, so here I've put left as X. Makes a difference.

[00:25:54]>> [laughter] >> Cuz I should have done it upside down, though.

[00:25:57]Back to front or round to some weirdo or whatever the freak it's doing.

[00:26:02]>> [laughter] >> I've basically gone on to Neil Fraser's GitHub page here.

[00:26:09]I'll link it in the description below.

[00:26:12]But, you can literally draw anything and um it'll appear on your oscilloscope.

[00:26:18]This is This is trying to be a clock. I admire the fact that it's actually trying to work.

[00:26:24]Yeah.

[00:26:25]>> [laughter] >> Like, if you were to take it out, you'd hear the sound.

[00:26:32]Do you know that motorcar in those old games? Those punk style games.

[00:26:46]>> [laughter] >> Basically, it's converted the clock image into the sound on on an oscilloscope it will look like that.

[00:26:57]On the on a on a normal oscilloscope, right? I'm just impressed at my little TV here, the fact that the poor thing's attempting it. Bless.

[00:27:08]I mean, it's not accurate, but it's it it's trying.

[00:27:15]I think that's really cool, though.

[00:27:18]I've tried different configurations.

[00:27:20]I've tried removing the resistor, you know, with the resistor and the different value resistor.

[00:27:33]Suppose this is a square wave.

[00:27:39]I don't know why I was curious about that. I just was.

[00:27:43]Okay, so this is successful, and this is just the beginning.

[00:27:48]See, I'm going to continue now just messing around and seeing what else I can do.

[00:27:55]>> [music] [music] >> A very special thank you to my top tier patrons. Rich Garbutt, Axel Dominator, Jason Maddison, Corey Ostman, Brian Mitchell, Mark Boseck, and Monochrome Minako.

[00:28:25]Thank you all so much for your support.

[00:28:27]I really appreciate it.

[00:28:32]>> [music] [music] [music] >> Woo.