using TV to display audio signals

SuperKoopa · Posted: Fri Jul 21, 2006 2:39 pm Post subject:

thanks for informations.

sincerely i don't understand what speakon is:D

Can you tell me the audio input coordinates? (I mean Voltage amplitude required power...)

dnny · Posted: Sat Jul 22, 2006 2:43 am Post subject:

blue hell · Posted: Sat Jul 22, 2006 3:29 am Post subject:

SuperKoopa · Posted: Sat Jul 22, 2006 4:09 am Post subject:

thanks!

i have a bunch of old computer speakers (power is 3-10W)
do you think i can drive the coils with this?

somewhere in this topic i've read that old TVs are betther than modern.
On ebay i have found this

(never post a ebay link it's so unaesthetic)

isn't pretty?

do you think i can take the risk of bending this?

[Blue Hell: made the link shorter, you can use edit to see how]

blue hell · Posted: Sat Jul 22, 2006 5:35 am Post subject:

dnny · Posted: Sat Jul 22, 2006 7:35 am Post subject:

you need to try - or you can wait that someone comes to your door and makes it for you. Smile

dnny · Posted: Sat Jul 22, 2006 7:48 am Post subject:

SuperKoopa · Posted: Sun Jul 23, 2006 6:43 am Post subject:

hey dnny!

have you ever tried all the other possible connections?

have you found other interesting visual effects?

dnny · Posted: Sun Jul 23, 2006 10:13 am Post subject:

v-un-v · Posted: Fri Jul 28, 2006 5:08 pm Post subject: This thread must be made sticky!

Thanks to Dnny who recently provided a link for this excellent thread and I was able to enjoy it once again

I've made it sticky because I feel it would be a great shame if in a couple of years down the line, it were to be lost in the great topical thread dungeon! Laughing

(If you see what I mean?!)

dnny

Hi Tom thanks for the stickyness.

i have got many questions to my e-mail about this so i think people are building these units. So ...
if you have build one please post comments and pics here.
+ if you have any questions please post them here.
this way others can learn from our mistakes and success.

daniel

SuperKoopa · Posted: Tue Aug 01, 2006 9:44 am Post subject:

hi! dnny

My tv is just arrived today and i have some problems!

This is the story from when i opened the tv box to now.

1)i have disconnected the coils from the board
everything okay, there was a dot in the center of the screen.

2)i have connected Horiz. board output to Horiz. yoke.
everything okay . There was a very bright horizzontal line in the center.

3)i have connected Vert board output to Vert yoke.
Crying or Very sad

i seen a very low brightness vertical line.

4) i have connected my stereo output to hor. yoke and it works but the brightness i so low!

5)i have thougth that this was caused by the protection system , so i tried every coils and transformers my home and i i've found different results.

5.1) a bit more brightness obtained from a secondary (15V 30VA) of a power transformer
i don't want use this, it's huge and too much heavy!

5.2)very good brightness obtained with a 8 ohm (3 W) computer speaker Shocked

this could be the optimal solution but it warms soooooo much!

what kind of dummy yoke you have used? where you have found it?

pleeeeeeease! help!

dnny · Posted: Wed Aug 02, 2006 3:39 am Post subject:

Hi Super - nice to hear that your TV arrived and you have opend it successfully but...as i said earlier:

SuperKoopa · Posted: Thu Aug 03, 2006 12:28 pm Post subject:

dnny · Posted: Thu Aug 03, 2006 10:20 pm Post subject:

SuperKoopa · Posted: Fri Aug 04, 2006 7:28 am Post subject:

I haven't built it yet but this afternoon i must go to Cagliari (55 Km from my city) Exclamation

at my favorite (and the only a bit eqipped with diy stuff in sardinia) eletronic shop to buy some RCA jacks and other stuff for my SL.

i will add an old stereo computer speaker amplifier and ten RCA jacks to make this unit completely patchable!

in this way you can amplify also the vertical board signal and put this to Horizzontal coil plugs to obtain a modulated horizzontal line (not vertical like in the classic version)

osc.JPG

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dnny · Posted: Fri Aug 04, 2006 12:17 pm Post subject:

sounds interesting - please post updates when you have completed this project.

Chrishipgrave · Joined: Nov 05, 2006 Posts: 4 Location: UK

I've tried to do this with my colour tv. Tried every combination of wires from jack to yoke and just get a dot?

Also, i re-connected the board cables back to the corresponding yoke cables and there is just a horizontal line (should get normal tv).

I've read that newer tv's don't work for some reason, i guess mine was too new? Anybody know about this?

Also now, even though i just get a horizontal line, i should still be able to get it to work shouldn't i?

Chris

dnny · Posted: Thu Nov 09, 2006 5:48 am Post subject:

there is a neat how to on geek technique. org
on how to make Mac se/30 audio visualizers

Posted Image, might have been reduced in size. Click Image to view fullscreen.

Posted Image, might have been reduced in size. Click Image to view fullscreen.

dnny · Posted: Thu Nov 09, 2006 5:57 am Post subject:

hi Chris

i have never tryed whit a color set, but if you get the horizontal line it should be enough. keep the horizontal line and then ad amplified audio signal to the vertical coil and that should get you the effect.

on some newer TV's the problem is that there is some kind of error detection and if they detect any error they will automatically shutdown.

Kerr_Avon

Buy an oscilloscope. They are cheap.

I'll give you one possible proviso on that: On a colour set it could give you multicoloured fun that an oscilloscope would not, especially on an old delta gun set with three audio coils arranged around the tube neck, driven with maybe L, R, and L+R. But bear in mind the much higher power of the EHT on colour sets especially the old delta gun monsters. And don't forget to make sure you keep all your circuits completely isolated from any metal in the telly including the chassis bits which look like ground - as they are frequently at full current 1/2 mains voltage relative to mains earth or neutral.

If you didn't fully understand that - don't open the set.

Chrishipgrave · Joined: Nov 05, 2006 Posts: 4 Location: UK

hi all,

I've finished circuit bending a black and white tv, but the signal is quite small so i've got a small amplifier which needs 10-30v DC and was wondering whether i could power this from the TV?

does anybody know how i could do this, or is it too dangerous?

Thank you
Chris

Kerr_Avon

No don't. And see above where it says "If you don't know what this means, don't open the back." The set might not be isolated. This means that the 0V rail inside the TV is likely to be at half mains voltage. Also I repeat, it's pointless for monochrome, as perfectly good old oscilloscopes are about 20USD.

Chrishipgrave · Joined: Nov 05, 2006 Posts: 4 Location: UK

Ok, i used a seperate DC adaptor to power the pre amp and it worked fine for a while.

After about 3 minutes of playing music through the preamp and into the TV i felt the pot on the preamp and i was really hot. So i took it apart and the IC chip has got a big crack all the way along it!

Does anybody know why this would of happened? I'm guessing it's something to do with the TV rather than the preamp because it was a kit bought from maplin.

Thank you
Chris