It is another nebula projecting laser astronaut, but this time it's different because it's completely dead and it comes with a cover note. hello Clive Here is an alternative Astronaut Nebula projector. It was purchased from Teu Uh for Christmas but was dead in arrival. Timu said there is no need to return it and have refunded.

presumably they want the E-w to be our problem indeed. I've opened it to look for anything obvious I could fix, but everything looks in order. at least nothing is burnt. So drawing except that I can see pretty sure I put it back together correctly.

The only thing I can guess at is a motor which is a two- pin connector shoved into half a four pin header. but I don't think that should cause catastrophic fear of the entire astronaut unless it's plge reversed. I'm not 100% which way it was originally also interesting the position of the infrared receiver which is inside the backpack. I'm not confident this could ever work.

How does the infrared get to it? It is the same 3+2 wires connecting the head as your for me, but the infrared presses the buttons. That will be interesting, right? right? So it came with this lead, so the first thing to actually do here is get a little power analyzer and just see if it's drawing any current at all if it's like a short circuit or something. So I shall plug it into this little rang analyzer. It's drawing nothing and then buttons.

nothing. Okay, let's rule out the obvious first meter. Is the polarity correct in this Is it even working? This is set to 20 volts. That's perfect.

So is the lead okay, and is the polarity correct? R In here? nothing. That's an interesting start. Hold on. I'm going to get the other lead from the other astronaut.

Just give me a second here. Where is it there? it is? That would be a very, very easy fix, but it never ever works out that easy, does it? I Shall plug this lid in here. hopefully the tip and ring of the crack polarity. Let's plug it in and push buttons.

Uh, the NAB projector is now working. It's the cable that's faulty right? So now we've done that. Let's explore it for is everything working here? Oh, there's the laser Mhm. not a very bright laser.

I Have to say God I Can't even see the laser unless it's oh, it's doing its fading thing right. Okay enough, let's open it up and see what the circuitry is like in theide how it compares to the other one. I took apart right I Shall tie a knot in this one just to remind me this is the Dff one. I could just stick it in the bin right now I may just chop the plug off at the end if it's that end and just use it.

As for the lead, so he says the infrared receivers in here, That's kind of interesting. Let's pop this open. I'm going to need a thin screwdriver for this that is not the suitable screwdriver. This is where I just scatter all my screwdrivers everywhere I didn't plan this did I Um I'm not seeing my screwdrivers one moment please I Found a suitable is screwdriver.

Let's see this infrared sent in here. Let's uh, zoom in a little bit. I Still have a box with uh, good chunk of fanfold computer listing paper in it from the era that I was doing quite a lot of software writing in Uh Ql super basic and uh Doss uh, what was the one with DOs it was a Microsoft Quick Basic I think it was what do we have? What do we have? What do we have? What do we have? Do we have the infrared sensor in in here? It may just see through the plastic. so unscrew that one.

unscrew that there is the infrared sensor. There is a power supply that's interesting. This is different from the other one, so it's got three buttons. uh I'm guessing it's power plus one of the the the buttons are all common to one reference, so this may be a standardized Uh voltage regular.

Supply Excellent. That's intriguing. What are we going to find in the head? Is it going to be the same mechanism as before with the Uh Distortion disc? Just basically. um, spinning inside a little sort of cradle which was quite an interesting construction.

Are these screws coming out? I Think they're coming out. They might not be coming out. They do feel very loose, but they might not just been snug in too tight. Which is good.

Not like those ones you get from China where they've just basically just run it right into. The point of this is completely different. What the heck? This is very different. There's the LED Source projecting down onto something that is then firing out at an angle.

This is very interesting. Can we get this out a little bit further? as this glued in, there is a circuit board. We should analyze the circuit board. There's a laser.

as is often the case. There is a little four pin connector with just two jammed on. I Wonder why there's two drives? Are there two transistors for driving that? It looks like there are two H options or transistors here. I'm not actually even seeing a transistor in one of those positions.

I'm seeing the three for the LEDs right there. Well, let's unplug everything so that one was in the one to the side that's actually a five pin connector this is wedged on. That's exciting. Uh, this is a little connector for the well.

this is the laser on here. These are well jammed and if these been glued in, it feels like it, but they may just be a tight fit. Here is the one for the LEDs and here's the one for the other bit. Let's WAP this out and see what's what's going on here.

This is very odd. A first time for seeing this now. the other one. the infrared receiver was actually mounted below this pattern of holes I Wonder how efficient this one is compared to the other one? I may try them next to each other and just see how bright it is at this point.

I don't even know how it's working. Is it a reflector that it's actually rotating a a chromed plastic disc and is the laser glued in properly? Or is it going to fall out like the other one did? This ain't comeing out too easy. These uh, screws required to come out too. Let's just take all the screws out.

That's usually a good result. now it's coming out. What a weird little mechan. ISM That is worth exploring.

How strange. Yeah, we'll have to open that up. uh and I shall. Also Let's see is the loser.

It's just wedged in again with the defraction disc in front of it. The defraction material just of jammed in there, right? Okay, well we know what we'll do now. I Shall uh, take a picture of Sucker board and we shall reverse engineer it and uh, then take it from there one moment. Please, Reverse engineering is complete.

Let's explore. So the unit is divided into two sections. This, it turns out is a power supply section. that's why it's got the inductor, it's got the infrared which sends data up, and it's got three switches which uses a voltage divider to provide a voltage level up to the top.

Let me Zoom down this uh a bit more so. the incoming Supply comes in the Jack here and there is a capacitor across that for General decoupling. It would have been nice to put a Diod in that, particularly given this is actually regulating down 3.6 volts. but they didn't.

This is the inductor that couples with this A616 3 Z Now, it's worth mentioning that that A616 3 Z is actually Uh Mt 2492. That's a good correlation of numbers there, and this Uh is basically it's a little Buck regulator that she uses the inductor to drop the voltage down by providing pulses and it effectively just kicks back against. it. acts like a a resistor to limit the current, but ALS but using inductive techniques, it just makes it more efficient.

And then there's a Uh voltage divider here that provides the signal back to the feedback pin and by changing the value of these resistors, you can set the output voltage. In this case, they've used 3.6 volts and the reason they've done that is to reduce the dissipation of the resistors for things like lasers and LEDs. Notably, the LEDs The infrared sensor is just tapped directly across that 3.6v supply and this pin goes straight up Um and the potential divider is formed by this resistor down here. and then these resistors are switched in by the Uh switches.

Let me show you the schematics for this section first: I've abbreviated it somewhat incoming USB Supply Smoothing Capacitor Mt 2492 Uh regulator and it produces the 3.6 volts that then goes up to the module. there's an infrared is tapped across that Supply Rail and then it goes up to the module and then the other module and then this is the 100K resistor going to the positive Rail and then each of these resistors is switched to the negative rail when you push the button and it just means the voltage in the switch connection that goes up to the other control module again. H Just when it sees if it says 3.6 volts it knows no buttons are pressed. If it says say for instance, you press this middle button it would be half that it be 1.8 volts that would go to and by looking at the voltage, it knows which button has been pressed.

it means that they could use one line for as many switches as they wanted. and then there's two other Connections in that Uh connector and it's two Zer volt connections. Okay, next circuit board here is the next circuit board the supply comes on here. There is loads of decoupling that capacitors dotted about left, right, and Center all over the circuit board.

There is a 4.7 Ohm resistor and a capacitor to provide a filtered supply for the microcontroller. Uh, the motors. The reason there are so many connections is because it can drive four Motors There's a common positive connection and then you've got 1, 2, 3, 4 each with its own transistor and um, back EMF diode. So there's uh one, uh, the one motor that is used with it 330 ohm resistor cuz it's a standard Npn resistor.

There's the second motor, there's the third motor, and there's the fourth motor. It's just basically four channels I wonder why they've done that? Then for the laser, we've got a 7.5 Ohm resistor in series from the power supply and we've got a A2shb mosfet switching that directly control for the microcontroller. And then for the LEDs we've got another three A2shb mosfets and a resistor in series of each color. So 4.7 ohm for the red, 1 oh for the green and 33 ohm for the blue.

Interesting, There's two positions for resistors here. Wonder why they've done that that? Maybe it was for the red was originally designated put there because the red has a high voltage to drop and more will be disappeared across the resistors. Anything else worth saying? No, that's it. It's one of those things that took a lot less time to tell you than it took reverse engineer, although to be honest, it wasn't that hard.

Reverse engineer here is the controller I'll Zoom down this a little bit. So there's the Uh Supply Comm on 3.6 volts, there's the Zer volts. There's the little decoupled Supply 4.7 ohm leading down to capacitor just to try and filter noise from the microcontroller. of the switching of things like Motors we've got uh, the Npn transistor, the j3 Y switching the motor there times four if you want cuz there are four positions.

the laser has its resistor going to the positive rail, then the laser diode have just drawn one little beam of light there cuz it is a laser and then going down to the mosfet which has a 4K 7 P down resistor but is driven directly from the microcontroller for the the LEDs This circuit is repeated three times. we've got the LED a resistor 4.70 1 ohm and 33 ohm for red, green and blue and then it's down to a mosfet again with the 4K 7 pool down resistor and that is it. Now let's take a look at the interesting Optical module this module here and it's not as good as the other system. It produces a different effect if we take a look at it.

I'll zoom out a little bit here so you can see it in more detail. I'll zoom out a bit more cuz it's very big. Yeah we have a this is the case open here. So we've got the cating lens for the LED circuit board.

The LED circuit board just basically has one of those Standard 1 wat 3 wat type beads on it and that uh goes into the end of this uh cating lens which is a total internal reflection lens and that focuses the beam down onto this rotating disc. The disc is rippled glass with mirror mirroring in the back and it's just straight onto the geared motor so that rotates slowly. The beam comes down, goes through the Ripple, bounces off the mirror, comes back through the Ripple again and I'll show you that effect and then gets diverted uh through this uh front lens and then far out the front of the unit. I Don't think there's any other lensing, that is it.

This is just a a clear cover in the front of this. However, it's not very bright. but see if you actually point the laser down through here into this, that's a very different matter. So I'm going to set that up and I'm going to show you the facts and what they look right right now.

So one moment please, the unit is now running. I shall turn the light off and show you what this looks like and this is it. I Have to say it's not as bright as the other unit. It's a nice module, but it really doesn't quite put as much light through as the other one because the other one is basically just the LED and then it's rippled glass and then a lens to focus that it's just straight out the front of the unit.

This one is trying to fire it through two layers of the Ripple Glass effectively, which produces an interesting effect, but isn't as good. Now let me show you it if I do a little hack and I put the laser through this Optical assembly instead. So I'll let you judge. Is this a better effect? I'm not sure.

Well, it's coming across on camera. It's quite a detailed, complex effect, but because the mirror, the laser is being shot into that mirror and then back out again, it creates a fairly complex morphing Rippling effect that covers quite a large area. It's not too bad an effect, but anyway, watch your eyes, the light is coming back. So in summary, um, quite a disappointing fault that you know the cable had basically resulted in the whole product being condemned as such because it's faulty H but quite interesting to take apart.

Very different to the other one. although it looks identical in the terms of the case. The whole functionality is different. The circuit boards are different.

It's strange that it's using the regulated power supply H to lower the dissipation. That's maybe a better move. This actually seems a more complex Optical assembly than the other one, particularly because it requires the mirrored Uh, presumably glass rotating disc the rippled disc. but it just doesn't pack out as much light as the other one does because Perhaps it is just trying to get too much into a small era.

But an interesting thing. A very interesting thing, and certainly smacking the laser into the Uh into the optical assembly provided good and interesting results. But there we have it. Uh, it was an easy fix.

It just needed a new cable, but um, to be honest, it's not as good as the other one. It's uh, just a bit disappointing in terms of performance. But other than that, interesting circuitry and an interesting Optical assembly.