Bigger Boob Tube

Have an tiny old TV laying around? Why not follow this instructable and create your own personal movie theater with it? Through these simple steps you can project an image of this television screen onto your wall that can be up to 70" across.
Materials:
1 Small (preferably under 15") TV
1 Mirror at least size of TV screen
1 Cardboard Box of similar dimensions to TV
1 Magnifying Glass
1 Roll of Black Tape (preferably duct tape)

*Optional Materials*
1 Speaker w/ speaker wire

Step 1 Measure your TV and locate a suitable box

You want to measure the perimeter of the TV, not just the screen. My TV was 10.25 X 11 inches, and my box was 10.75 X 12 inches. You want the TV to snugly fit inside the box, allowing as little light to escape as possible. But don't worry if its not a perfect fit, thats what duct tape is for. The box should be roughly twice as long as the TV because you control the focus of your image by moving the TV back and forth. After you find an ideal position you can shorten the box for spatial issues.

Comments

[Ideal_Ideas91]

Ha Ha! Pointless Step As My TV comes with a Headphone jack! So all I need are some headphones, scissors, and a speaker! (I Know some tvs dont have Headphone jacks But I wanted to say HAHA, And I Did.)

[HAZMAT2364]

wouldn't the image be reversed?

[HAZMAT2364]

Would you be able to make the projection come out the front of the box? if so, how?

[Ranie-K]

An idea (I wonder if it would work?): How about adding the arm from an overhead projector over a CRT screen (laid horizontally)? You should be able to scrounge an old overhead projector and an old 14" CRT monitor for nothing. No cardboard or anything -just the arm from the overhead projector epoxied to a CRT monitor. Perhaps also epoxy a few pieces of junk so the CRT monitor will lay stable "on it's back". What's your thoughts?

[joeny1980]

This has been around the net forever, I was very surprised when I searched instructables and never found this project. It is typically called a "100 inch tv". I have personally made it. I wonder how this poster's results are because his design is not typical. You need more of the lens exposed b/c the lens is a light collector. So he must have a VERY dim picture. I could be wrong though.

There is a great thread about it here:
http://www.greenspun.com/bboard/q-and-a-fetch-msg.tcl?msg_id=0038A5

But here is my own comment from that thread:

"I just came back to post my results from my experiment with my new ghetto projection tv. To those who say that it is total crap, u must not know what your doing b/c it works. Now let me first say, of course noone "expects too much" from a projection tv made out of cardboard.
I only wanted to try it out and see what happened. I tore apart an old boombox cardboard box wiht a razor blade, yard stick (barely used it), and some duct tape. i didnt bother painting it. i threw this together in 10 mins. i didnt want to waste time if this thing didnt work. i hooked it to my 13 inch tv, at 3 oclock n the afternoon, 3 windows in the room, shades up (in other words: it was NOT dark). and ta da, i got a pic. i didnt make it huge maybe only like 4 feet or so (bigger than any tv i have), i can see how if u get bigger it might not be sharp unless in perfect darkness. But u ppl who are taping aluminum foil on windows and all that are nuts.

My rig was pretty crappy, i mean youi could see the light coming ouit of the edges and it still worked! not good enuff to watch but if i cleaned it up i think it will fulfill most ppl's expectations. im gonnna make it nice and out of fiber board probably. i want to build it into a coffee table or something. and yes its true ur screen gets screwy when u turn it upside down, i aint gonna do that , im gonna first get a sharp picture first THAN work wiht mirrors, i know it can be done. i used the very same box and and filled the space with a towel and used it on my 9 inch tv, it was just as good.

one thing ppl were sayin was , they took the fresnel lens and just held it in front of the tv and it worked better. i can see that may be true. the reason I think is ... is because u kinda jam in the lens (taped to the board) and it bends the lens causeing blur. u definitly need the box itself though , i think just to catch all the light and to stop the light from coming out from behind the lens and shining on the wall.
"

[Sincere]

if anyone is really interested in building your own projector check out the forum at lumenlab you can build HDTV 1080p projectors if you wanted to. Or just build a cheap one using a psone screen. Here is a actual picture that one of the guys built. Gears of War 1080P!
http://www.wavetel.us/~jonjandran/gow.jpg

[killerjackalope]

my 50 inch LG would be less pixelated but is easily beaten for space and room focus as the LG dominates the room off or on it's masssive and literally partially eclipses the sun in the living room but it heats the room to a nice temperature

[novice_geek]

A WORD OF WARNING TO ANYONE WANTING TO MODIFY THEIR TV... Because of the high voltages inside of a TV (which are always there, even when the set has been unplugged for a long time), you should NEVER disassemble a TV unless you are 100% sure of what you are doing. Also, be careful, as there might be some kind of radiation inside of the TV (if you start trying to take the tube apart, which you shouldn't be anyway). Just remember... if you do want to do this, take your time and be careful! Another option would be to connect that speaker to whatever device is providing the input to the TV. if you are using cable TV, then I would recommend using a VCR or something to change channels (and you can use the remote that way), and you can grab your audio off of that. Good Luck everyone, Novice_Geek

[davidlaska]

Has anyone tried laying a laptop LCD screen on a Overhead projector. The laptop would have to be next to it and there might be some cabling in the picture but maybe some models are less. Crop it out with cardboard or etc. I know the overhead projectors are expensive units but I picked one up at a second hand store for a few bucks and parted with it before I got this idea.

[boy-builder]

How big is the hole suposed to be that you make in step 2?

And can you use magnify glasses that are like 3 in diameter?

[Weissensteinburg]

Could you show us an image of it on the wall?

[knewman]

Well there is a problem, I tried to take a picture of the image but it was too dark to be captured correctly. When I tried to up the exposure time the image became blurry to the point where it was pretty much just a bright square of light on my ceiling. So sorry no pictures :) (I tried to edit my instructable last night to say this but I guess it didn't save?)

[Weissensteinburg]

Did you try using a tripod? I'd really like to build one of these, but I want to know what i'm getting into ;)

[joeny1980]

Weis... do some googling you'll find images from these types of builds. But they are difficult to take, they are pretty dim. Read my post above to understand expectations. Its worth messing around with if you dont spend more than $10 on materials.

[mark101]

Bad plan when you cut even/straight across.You should always stagger your cut 1/4 or half inch away from each other. That way if your insulation falls off you still don't have a short circuit when the wires touch(the metal on one wire is too far away from the other metal).

[little_genius241974]

I have done this before...great minds think alike?

[j626no]

hmmm...nicely done. how clear is the picture though i wonder? would a flat screen TV or even and LCD (brighter) monitor make it any better? I've got tons of boxes lieing around and thanks to trebuchet i know that all i need to purchase is a new FRESNAL LENS.haha. great job!

[knewman]

An LCD would probably make it brighter, I'd like to try it with one of those. The picture is pretty good but remember it is limited because I used a plastic fresnel lens (which isn't exactly ideal for this project) rather than a convex lens (usually found in a magnifying glass).

[indyguy]

Nice instructable. Fresnel lenses are definitely handy. This is not a bad idea for the type of visual source you are using. I would like to note though since you are using a 15 inch TV, with a 15 inch LCD screen you can make your own LCD projector. A great website www.lumenlab.com is dedicated to such a topic. If you already have a LCD screen (laptop or stand alone monitor) the rest can be done QUITE cheaply. Plus you get to use tools!

[knewman]

I actually have an old laptop around with a nice 12" LCD that I would have used, but I'm having trouble getting it to separate from the machine in one piece. Maybe when (or if) I get it off and add a tuner to it I'll update this instructable

[royalestel]

I'm going on the record here to say 1)Thanks! This is way simpler than the lumenlabs project and it's crazy enough, it might just work for my needs! And 2) That, my friend, is definitely Frah-nel lens, but in France and Quebec they spell it Fresnel. Heheh. Silly French spelling rules. Glad we don't have any wierd grammar rules like that in English. That would be wierd. . . Weird . . wired? No, definitely weird. Ah, whatever, I'm in a great mood--I'm totally making this! Thanks again!

[knewman]

Oh wow! Thanks for the comment and good luck making it.

[mikesty]

Fresnelolololol :D Dude, good idea, but for the speaker thing, you ought to pipe the cable into a receiver of some sort, that will also act as an RF modulator. This way you can plug devices (DVD/consoles/whatever) into the receiver where it will be displayed on the TV. It should also let you pipe audio data out to wherever you want it to go. Where'd you get that lens though?

[knewman]

The lens was available at my local staples for about 6$. Thats a good idea for the speaker, I'll have to try this when i have the time.

[trebuchet03]

It's worth noting that the magnifying sheet you are using is known as a Fresnel lens ;)

[knewman]

Ah thanks, I probably should have noted this.

[meddler]

This is neat, could you use wood like plywood or do you need the slight give in cardboard to get things to fit?

[knewman]

I think your measurements would need to be a bit more exact to use wood (something that I wouldn't be too good at heh) but I see no problem with using wood. It would certainly look much nicer!

[lennyb]

nicely done. i wonder if the image would be brighter if you make the aperture {hole under the lens} wider. may try this one myself. and since everyone one else said it or something like it...."wass iss loss mit der freshnel lens mein herr'

[bmlbytes]

I've seen this on the internet all over the place. And yes the other 2 are right, this is a Fresnal lens that you are using. Good luck though.