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Electrical engineering
Course: Electrical engineering > Unit 9
Lesson 3: DVD playerWhat is inside a DVD player? (1 of 5)
In this video we explore the housing and functions of a DVD player. Created by Karl Wendt.
Want to join the conversation?
- How does the dvd player know theres a disc in it?(7 votes)
- Because the laser must be able to read the disc.(14 votes)
- Also what is the difference between analog and digital, like the red, yellow, and white cables, versus a HDMI cable?(3 votes)
- To expand on APDahlen's excellent answer, let's take an oldie but a goodie- an Xbox 360 s. It has output to both- HDMI and an adapter to White, Yellow, and Red. However, if you plug in those to a TV which supports both, the HDMI will crush the three colored cables simply by being better at transmitting signals - for example, analog can't transmit 4k 60fps signals, but digital can. Of course, now the 360 has less graphical power than, say, an XB1 or a gaming pc, so you'd sometimes be better off looking at a less resolution screen (because of huge aliasing), but that's a story for another day.(2 votes)
- Can you do a video on how a TV and phone work?(3 votes)
- Easy- a TV probably has an lcd screen, which was talked about in the Digital camera episode. A Phone is harder. A smartphone is like a smaller, less powerful computer. I'm not sure about normal phones, though. Maybe search it up?(2 votes)
- how is the CD read?(2 votes)
- The laser picks up the bumps and groves on the the CD. I forget which one is which but one is 1 and the other is 0. Which is binary code.(3 votes)
- What type of micro chip does this DVD player use?(2 votes)
- Something extremely low-cost and weak, I expect.(1 vote)
- What would happen if you used a play station 3 DVD player?(2 votes)
- Any dvd player will read any disk- as long as it's not the other type (blu-ray vs infared, infared vs blu-ray). A PS3 dvd, like one you'd find in a Desktop, laptop, or the one featured in the video above, would work. I'm not sure, but I think the latest generation (XB1, PS4) can read both infared AND blu-ray. Gotta read up on that.(1 vote)
- why did the cd was mencion(1 vote)
- Why most dvd players get stuck and does not open again and I have to buy a new one every so often?(1 vote)
- Because you probably shake them around? If not, you consistently buy the same one and it's bad.(1 vote)
- how do they mold the buttons in place and still have them pop in and out(1 vote)
- no interactive transcript?(1 vote)
Video transcript
- [Voiceover] All right,
today we're gonna take a look at this DVD player. We're gonna see what's inside
it and what makes it work. There are several key components to this. We'll be looking at the power supply, the control board and the CD tray, as well as the laser itself
and the external housing. So let's go ahead and get started. This DVD player is actually very low cost. You can buy it for less than $30 and the way they've been
able to reduce the cost, part of it is that the
actual chips inside it needed to make it run have come down in price, and part of it is that
they've been able to simplify the components on the board tremendously. There we go. All right, you can take a
look at the insides there. This piece of metal is,
again, was just a flat sheet, was run through a press which created these tabs here and the tabs lock in the
housing under the front part. It also had these
indentations stamped in it so the screws would sit flush. And then the holes were punched
in it and it was folded. Okay, so you can see
inside the DVD player here. I do have it plugged in. Never safe to plug in an
electronic device when it is open. So, do not try this at home unless you have a professional with you. But I did want to show you
what happens when the DVD or the CD gets pulled into the player and kind of how it works. So what's gonna happen is
the tray's gonna come in, and you'll see this back
plate here lowered down to make room for that tray, and then you'll see it spool up. Then the laser will move
across, or, the laser assembly will start sliding across the DVD and you'll see that happen here. So, you can see the power's
on, the LED indicator's here. I'm gonna go ahead and close
the tray to bring it in and then press play, and you
can see it spool up there, and what's happening is power's being fed from this board here all the
way over to the control board and then the control board is
telling the motors what to do and gathering information from the laser. And then it's sending
it to these ports here, which go out to your TV
and show up as a signal. We're going to try and remove
the front panel of this unit. There we go. All right. So the front panel basically
is an injection molded plastic piece. It houses the slot through
which the CD tray comes out of. It also houses a window that the infrared from the remote control can penetrate to tell the thing what to do. And it has another little spot for an LED that indicates whether the device on and, or whether it's turned off. And then on the top, there are a number of different buttons. Those buttons are separate
pieces molded in there. There's an eject button,
a play/pause, a stop and a power button, so
fairly simple design. And this piece is probably
made out of ABS plastic. I don't see an ABS mark on it. It has these tabs, which snap
into the rest of the frame and make it easy to attach,
and fairly low cost there.