The Music visualizer is actually a second build based on an earlier design[Thanks Roger]. The build was influenced by Zyra’s How to make an oscilloscope out of a television. The hack is quite simple, patch the output of an amplifier into the vertical deflection coils of the CRT. This is a good use for that old TV you may have laying around but don’t want to recycle it just yet. While on the subject we had covered the Mac SE/30 audio visualizer in 2006. For those looking for something a little more hard core, here is a bit about Homemade cathode ray tubes.
Simple(ish) sawtooth oscillator (/|/|/| etc) and triggering circuit = great success.
i did something like this with an old macintosh (70 cents at a thrift store!) when i was in high school. you can wire both axes to your stereo for swirly lissajous-type patterns or leave the horizontal connected to the computer for a regular oscilloscope type readout. there are controls for focus, brightness, etc. in the guts of the computer. removing the case is a bitch though if you don’t have the right screwdriver :P
of course now i don’t need it because i found an old tektronix analog scope at another thrift store…
hey i did this before him! its on my freakin website under minitv!
^ NOTE googfan’ sig is a reported attack site. Please remove that comment.
@submission. Sweeeet
@bcoblentz
Did you dig the signatures inside the case once you got it off?
… We control the horizontal, we control the vertical…
Pretty old
@addictronics
my site does not attack you. every time i update my site someone, somewhere injects my index.html with code. the code doesnt do anything but i dont want it there.
ANY HELP IS GREATLY APPRECIATED!!!!
@addictroinics
just fixed it. wiped my server and re uploaded everything.
Who still has CRT’s? and who wants to get a dose of radiation as the bundle goes out of specs, how about putting an xray plate behind you can dub it a homemade xray machine for creds? :)
@wwhat
crts put out a very small amount of xrays. cover your nuts and your fine.
@wwhat Lots of people still have crts lying around. They’re pretty toxic if landfilled, but it’s hard to find a place to properly recycle them. Turning them into art/conversation pieces like this seems like a good way to save them from the trash. However, I do think the safety warnings on these links are insufficient. Is it really enough to just say ‘watch out for the caps’? I think the instructable should include directions for properly discharging them before starting the mod.
this hack, while always fun and cool.. is older than me (30 plus).
great selection of music by the way.
And I want to add.. *discharge the CRT before working on the monitor!!!!!!* the crt is in effect the largest capacitor you will ever likely lay hands on. respect the lethal voltage potentials.
love this! i did it last night, but it’s aligned wrong. :) it goes vertically on the screen, and i can’t get it to go horizontally. oh well. i managed to get everything i added on to the TV to fit into the original case (using lots of hot glue and shipping tape)! fantastic!
CRT’s do indeed put out very little xrays, when used within specs, but when out of spec things can go wrong, and the thing is designed to have the beam scan along the entire surface and to have the acceleration of the beam kept within a voltage range, now the voltage is limited by the parts too so it can’t get that out of hand normally, assuming you don’t change the protection, but when all the electrons land on one spot, well that’s not how the design is meant and it’s not what is protected against.
And the older the CRT the more tricky it gets probably, I’d be careful and advise measuring it to be sure.
@reefer:
Turn the screen on its side.
recently my band played a show with 3 tiny travel tvs and one 14″ i would stand on, all doing this to the vocals, all vertical though, it’s easier and weirder. i had to gut the amp from some computer speakers to drive the coil well from line level though. easy and cheap at thrift stores, thank you digital changeover!
@gromit i did, but thanks for the advice anyway!
you can see my diy-scope at: http://www.youtube.com/watch?v=jFgBR993JXA
ps: i know the sound is screwed up in my vid, i’ll add closed captions later
We have done a pile of these whit color CRTs:
http://www.flickr.com/photos/dnny/3697467909/
although this is an ancient hack it is still awesome. my only criticism is that there is nowhere near enough emphasis on the fact that if you just dig into one of these crt’s without proper precautions you could KILL YOURSELF.
just as a heads up.