Definitely. NEVER put your fingers behind the rubber HV cup fixed to the tube - I once did this on the back of an old colour TV more than a day after it had last been powered, forgetting that the inside coating of the tube would still be holding a charge. The force sent me flying across the room and I guess I was lucky not to have been killed.

That's just theoretically, forget what you study, I always work with this kind of stuff and there is no problem, the only dangerous parts are the big capacitor but not a thing to kill and the THT output, nothing else

You're more than welcome to make a video proving what you said :)

Can't agree more. The only time I took apart an old CRT, I made sure I took all the safety precautions and discharged he CRT. The spark is surprisingly large, and could definitely be a lethal shock. Stay safe out there!

There is "only" 25Kv on this modern color CRT.

I just remembered that I left the original yoke connected but set to one side. Then I slipped another yoke onto the CRT that was connected to a stereo. Important to the HV to keep a load on the horizontal output.

Henry Pitts When I made this test on a 1969 color TV, which still used vacuum tube to drive the horizontal/high voltage (+25kvolt), it appeared to work well with horizontal yoke unplugged. in case of overload, such as short circuiting the high voltage, the tube plates were glowing red but survived. With fully transistorized TV, any small stress and the high voltage transistor is destroyed. Not really friendly to curious experimenters.

@@Henpitts You must have done the _exact same thing_ that my highschool electronics teacher did! ;)

Can you help me do that with an old mega watchman TV please Henry?

Lissajous pattern? The logo of the Australian Broadcasting Corporation.

So did you connect the CRT deflection coils X and Y axis to the Left and Right channels of an audio amplifier? As i just wanted to know if that was how you sort of got a 3D affect on the CRT display.

@@ewansbuzz127 Yes, left and right to X and Y. To an old school transistor and heavy transformer amp. As a note decays subtle changes to the frequency takes place, and the left and right are out of phase, resulting in what appears to be a rotating loop or infinity sign. Best to find an actual oscilloscope to observe the phenomenon.

Superportvein neater than most native English speakers huh

Superportvein he is also left handed, which adds surprise.

Ozzeip Piezzo really? you learn something new every day I guess. thanks

A lot of native speakers learn to write when they are like 4 years old, and then never attempt to improve it :P This is true for a lot more languages than english.

ikr, thats the power of a gel pen

Thinking quickly, Dave constructs a homemade megaphone using only some string, a squirrel and a megaphone

it is the same: "using gears to make more gears"

Well not really He used a function generator

*sOuNeeDaNoScIlOsCOpEtoMaKeAnOsCiLloScOpE cLiCkBaiT!!!* (and yes, i know, it was a function generator and not an oscilloscope)

Oscilloception

ukposts.info/have/v-deo/bXaKemusn3mrooE.html

Marek S that sounds awesome and would probably be more interesting for most of us

You could do this also on an oscilloscope. Nothing changed. And also mentioned and Scott replied.

I think they mean a spectrum analyser, maybe? Like you get on EQs?

As he stated, it couldn't be used to perform any accurate representation as the crt was not tuned to perform this function.

This is a good idea. CRT give much better view of the music than a few LED Using a color CRT, I suggest the following: 1 - disconnect the horizontal, but replace it by an equivalent inductance. Most TV require a continuity on the horizontal deflector as protection for the CRT. The high voltage fall to low level if the horizontal is disconnected 2 - connect the horizontal to a 6 volt transformer. We want a 50 Hz or 60 Hz sinusoidal wave, not the saw tooth wave shape of a typical scope 3 - disconnect the vertical deflector, connect it to your audio output of an amplifier. The impedance is around 8 ohm to 16 ohm, similar to a speaker 4 - disconnect the 3 wires that control the red, green and blue of the CRT that comes from the main board going to the PCB on the rear of the CRT. Apply 3 volt DC. This allow the beam to be constantly ON instead of flickering with the video data. You may still get an annoying black portion which is the retrace blanking. This can be removed by increasing the total brightness, a voltage control located on the high voltage flyback. If there is potentiometers on the PCB on the rear CRT, increase these as well to eliminate the retrace 5 - Use a magnet (from hard drive or micro wave or speaker) near the read of the CRT to separate the 3 colors. Modern CRT have such excellent convergence that the lines would be just a boring white. Move around the magnet until you find a location where each color separate, while avoiding to mix the color. You want the 3 saturated red, green and blue, not a mixed half ass of yellow, purple all jumbled. 6 - You may want to swap the horizontal/vertical since the horizontal can be swept 300 times faster. In that case, rotate the deflection coil by 90 degrees. This modification of a color CRT display music in a really majestic way. When the music contains lot of bass at 50/60 Hz or any higher multiple, very nice lissajous shape appear. The 3 colors are much more interesting to look at, compared to the boring green of a typical scope. If you own a function generator (as you mention in the video), replacing the AC transformer by the output of the generator, going thru an audio amplifier, you can set the scan frequency to the dominant frequency of the bass for each music you play, allowing these lissajou figure to appear. A further improvment would be to use a phase locked loop to detect the bass frequency on the fly. Displaying the locked frequency would complete the design for a tool that reveal the musical note for each base tone.

there is a thing called notification

"People with too much time" Damn I wish I had even enough time to study

K1ngjulien_ people with no life 😂

don't you think that you have no time for you own interest because you are working on somebody else. somebody else like the one who created experiments like this.. before there where business and jobs there are people who do the testing and invent things for their own satisfaction not for money.

K1ngjulien_ me

Damn that sounds cool, I want to see one of these modified units

Gijs gotta love that high frequency sound. Mmmmm

look up DH3-91

Gijs I have the same feeling

I wish there is a speaker to salvage in the that tv...

they normally have a sharper picture, which leads me to think something was wrong with the one in the video, appeared to be out of focus which is usually not a good sign (symptoms of a weak crt), maybe it can be adjusted.

Thanks, I will try to keep it up.

"scoot"

craftxbox Aha

U Liked Your own comment?

i didnt?

craftxbox "i" Oh,that grammar...

Cool, if you want, you can also check out my version on my channel :)

your TV oscilloscope is the best on the entire internet! Congratulations!!!