Ben Heck's Mechanical Television Part 2
ฝัง
- เผยแพร่เมื่อ 14 เม.ย. 2016
- In this episode Ben continues to make a mechanical television using old records, a flash light, a drill motor and some Photoresistors.
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Well that was a colossal waste of my time. If i wanted to see failed projects I'd go down to my basement.
+riffraff60 not a waste of time but I am with you regarding basements
if i wanted to see failures, i'd look at my son
It goes over basic principles, and 31:17 shows that it can render something. This is the kind of project that requires precision engineering rather than prototyping techniques, so I really wasn't surprised by the outcome. It was interesting.
AIDS Bjorn yea exactly, it's incredibly simple as far as materials so it requires incredible precision in order to work properly
xMurrCattx loved your reply haha
Definitely want to see the Mechanical TV revisited. Probably the most interesting idea for an episode in quite some time. Go big or go home!
Totally agree. Very disappointed to see them give up on it.
+Mooncabbage I second this. This device changed the world in a way that was almost magical for most human beings I'd love to see it working in the naked... Maybe it actually used magic?
I agree please revisit
I would like to see them pick it up again as well. A lot of hobbyist knowledge about tv was circulated in the 1930s but most of it is unusable today.
I agree that the way the image is created is a kind of "magic" to us in a fully electronic age. It is not just lo-def. It looks like nothing else because of how it's made.
It's really close to working. The picture generator (receiver/viewer) is correct. However, the camera end of it isn't correct. Two suggestions...
1. Cameras don't project light, so pull the flashlight out, and shine the full light on the subject being filmed. Try the camera out before doing number two.
2. Either centralize the photo diodes, or use a larger photo sensor (like a solar cell, or ancient selenium photo censor). Make sure that the photo sensor(s) is in the same position on the camera as the viewing port on the receiver.
That should give you an image, however you may need really strong light for better imaging.
Wow, you gave up on the project? Seriously? ... and for the doorknob, just use copper -_-
Imagine making one of these in the 1920's with out all of the technology we have today, and have it work.
Shows how brilliant Logie Baird was, he in 1926 (or around that time) managed to build his ''televisor' with an old coffin lid and bits bought in and around his local high street 90 years ago, without any previous knowledge or help, only with know how of the Nipkow disc as a starting point.
+mart fart Not only Baird managed to build a working camera and monitor, but he also developed quite unique way to transmit the signal. The modulation (AM) was made possible by use of a disc with multiple slots obscuring the light. It was playing the role of a RF generator.
100% revisit this in the future, to think I was minutes away from asking you if you've ever filmed a failure/incompletion and shown said failure/incompletion in an episode.
Actually the best door knob desinfecting device was in Home Alone 1 where he put the heater on door knob :D
Felix's Guide to Install Arch Linux. Episode 1 of 200.
+ cpp_hleucka Arch fanboy detected
+cpp_hleucka latest version of vim, yea, that shit changes alot
+cpp_hleucka personally, i run slackware and love it. if i need a new version of anything i just compile it, but yes its all about preference and would suggest anyone to at least give linux a try
Felix's Corner was a great idea!
The BBC were recently able to recreate a mechanical television system, when they recreated the first night of regular television broadcasting (80 years!) in the world. So it can be done.
It was a really interesting programme - it's called "Television's First Night". You can probably find it on the BBC iPlayer.
Revisit this project! Using stepper motors as Ben said might help.
+Erikgasm Actually the way to go would be to use brushless motors - steppers are way too slow for the speed this needs.
You're over complicating the system. Stick to the original design, and it will work. Use AC Synchronous motors to drive the Nipkow discs. Use a simple valve (or transistor) amplifier to boost the signal. Though your "transmitter" seemed to work, it would benefit greatly from a more powerful light source than an LED flashlight. Try an old Halogen movie light. The original system used carbon arc lamps.
He is busy buying some tools to break apart...
Radiomovies, Radiovision, Television by Charles Francis Jenkins-1929. Also, his book Radiovision has lots of information. The first book has mechanical details and tube circuit schematics. John Logie Baird did it in England about the same time.
You could use a brass doorknob. The copper in it is a natural anti microbial.
+RickMakes
Yeah, but that only works if he never ever use the doorknob..
The salt in human sweat actually forms a corrosive layer that prevents the electrochemical process that kills the microorganisms.
+MiniDemonic mind blown
+MiniDemonic Would that still occur on a (cost prohibitive) pure copper doorknob?
+kevin trask It's all about silver, myaaan...
***** The studies I've seen on it was made on alloys, not sure about pure copper.
the most impressive was to see the amount of work that has gone to something which didn't worked. this encourages me to continue to learn trough failures
Don't let the negative comments get under your skin! To me, this show is about teaching DIY, and so showing your failures (and how you deal with them) is very important. Show folks that failure is not only OK, but essential on the path to success. Don't be afraid to fail!
1. Thank you for showing a failed experiment--I need this to stay sane as I ruin project after project :)
2. All hail Felix
3. This team is awesome and I hope the tv comes together eventually!
Love this project! It reminds me of an idea I had for a mechanical computer that would be punch-paper based, had a mechanical TV display and Vinyl jukebox style sound playback...
Oh yes. Please revisit this. I'd love to see it work.
I've been watching the channel for well over a year now, first time I have commented. I am really disappointed this is being left here. Perhaps back to the drawing board and a whole new approach is needed. As a project it's probably the most interesting that has been tackled. I would really, really like to see more time put into this one.
I think breaking the project up into the two halves is probably a better idea, and tackling them as individual units, rather than trying to jump in with two episodes and completing two quite complex pieces of machinery.
As others have suggested, I think it's certainly worth setting up a monitor so the information that is being collected can be displayed, and having simply an on or off value is a terrible idea. When you have such little resolution already the series of grey/ brightness is the only element you have going for you as is.
Looking forward to the next episode, but I really want to see this revisited.
Come on Ben, finish that mechanical TV! Don't let it defeat you. If it takes 4 episodes, I'll keep watching.
Felix's corner is getting better and better.
But it's not like he's up staging Ben. it's a complementary thing
Complete what you have began. Don't give up.
I would have used DC motors anyway or brushless motors. Stepper just can't reach high enough speeds; instead of a microcontroller, you could have used the Phase and frequency comparator of the first stage of a PLL, ignoring the VCO. This way you could have driven the motors with PWM. I know it would have got more complicated, but it would have been worth it, as most of PLLs integrate almost every component needed to have a DC output that can then be used for the PWM comparator. I've gone into several of this issues as I was trying to build a mechanical laser video projector and although it didn't work in the end, the speed controller made this way was performing pretty well.
Interesting idea.. I want to see part 3 of this. As for ideas I have none.. lol
2 episodes, 40 minutes for a quick text saying "Project failed"?
I'm all for science and stuff, and it was awesome watching this. Though I do feel a little bit cheated, I learned enough from these two episodes that it was worth it.
The original mechanical tv did not use projected flying spot. It focussed an illuminated subject onto a sensor and the scanning disk was placed between the lens and the sensor (or the subject and lens). If you want to sync dc motors then use the back emf control method, Very simple circuits can be made to do this and you can create very stable speeds..
Lol 14 min to find out they couldn't build it.
For synchronisation: maybe add one hole that always has a light on it, so you can use the blinking of that to get the timings right?
And for door knob sanitizing: bare metal is already antiseptic, so a metal door knob is already self sanitizing.
I can see that idea working! Using a mechanism like that to sync it? awesome.
+Bart Stikkers Only copper alloys are antiseptic as far as I know.
+1blisslife Add my vote to that; basic timing light. Great idea. Still need to build the system tight enough to make it tune-able though.
Ben Heck always take something sample and make it complicated.
This project really intrigued me. It was a real buzzkill to find out it didn't work at the end. I'm sure you guys did your best and it would be great to see this revisited successfully.
I'm glad Felix has a segment now. I really enjoy his content. He compliments Ben very well. As for the project, I'm bummed that this didn't work but I'd love to see you do this again in the future with ideas from people smarter than I am. :)
I enjoyed the two episodes, was hoping to see it work, oh well can't win 'em all. Hope you do try again. Keep up the good work!
Way to go, Felix! Incidentally, I'm watching this on Arch :3
It's definitely not a distro for people who whish their computer to abstract away all the complexity and "just work" but for someone who seeks a deeper understanding and who has the patience and time resources to first discover how they want the system to be like and then to go set it up that way.
Absolutely you should revisit this and finish it. I would do the record sync with some sort of PLL circuit so the motors would try to match the RPM and the position of the rotating records.
Please revisit!!
1. Analog brightness signal !!!! The source brightness should directly control the playback light brightness. Simple analog stuff. Get rid of the comparators here!
2. Sync records with some sort of analog encoder, (potentiometer, ideally) so you can get high speed, and absolute positioning.
3. Servo the playback motor so it is in sync with record motor.
Simple comparator circuit here:
If the playback motor is ahead of the record motor, the comparator goes low.
If the playback motor is behind the record motor, the comparator goes high.
4. Low pass filter the comparator output, (capacitor in the feedback loop of the comparator) so it becomes a slow moving voltage. Put a high current buffer (power amp...) on the filtered comparator output that directly drives the playback motor. Boom, synchronization!
5. Transmit the record brightness signal and the record encoder position over two AM radio signals. It is TV after all!
OTHER IDEA:
Instead of a spinning record, use lasers and a XY mirror control, like a barcode scanner. Use the mirrors from a laser printer or barcode scanner? Way better resolution. LASER TV!!!
For a simple demonstration I would just cheat and run both the receive and transmit nipkow disks off the same axle. That way the number of revolutions per minute will be exactly the same for both transmit and receive. The tricky bit then becomes - how do you get the proper number of revolutions per minute to display a good image? probably just a potentiometer controlling the current into the motor would suffice.
A more sophisticated setup would use an Arduino to exactly control the number of revolutions per minute at both ends.
its the best show i have ever seen nice job guys .
Solution is pretty simple - do what CRTs do. Have a sync pulse for every rotation (1 extra hole out of the frame area + 1 extra sensor), and in the receiver, have a phased lock loop that syncs to that pulse, which controls the motor's speed.
i love how karen kept ben motivated. good chemistry.
In the 1920's, many DIYers building this used oscillating fan motors, which are AC induction motors. In the articles I have seen, they would just take the blades and blade guard off and mount the Nipkov disc on the motor shaft. I think if you tried this again, you should try it with a couple cheap oscillating table fans. I think the speed regulation would be much better than you think. Many record players from the 1930's to the 1970's used induction instead of synchronous AC motors.
Since you already had the mechanical structure built using dc motors, couldn't you have just added a tiny magnet on the spinning record and use a hall-effect sensor to get a timing pulse? If balance is an issue, put a magnet on both sides and then half the frequency/ignore every other pulse. Its a thought anyhow, good luck!
You really need to go to the NBTV forum where they make working mechanical televisions and cameras
Felix´s corner is great!
Revisiting would be great, I liked where this was going.
Aw man. I was looking forward to seeing this working. Felix's Corner was awesome though :)
I've never seen you fail before. Please warn us at the beginning of part one from now on as for the first time I feel like I wasted my time watching an episode.
Why would any TH-camr be honest about the out come of their videos if they're trying to get views? I don't know what world you live in, but that's not how the world works.
Super Cartoonist garnering goodwill amongst your viewership goes a long way in a world where there are countless places to find entertainment.
@@jmholmes83 Yeah, but we don't live in a perfect world so we are going to come cross people like this, regardless or not if they care about wasting our time.
So sad! I was really looking forward to this, I've been very interested in the concept of mechanical televisions in the past. Ben, if anyone can do it, you can!
For the mechanical television I'd suggest moving from a disk to a belt, perhaps something with roughly the dimensions and speed of a belt sander, which could probably net you something in the region of 15 to 20 fps. The obvious advantage here is that you could present the playback in rectangular instead of a slightly curved pattern, not to mention the overall size to screen size ratio could be somewhat minimized. I would also advocate forgoing any image capture in favor of a converter for playing back pre-existing video - perhaps you would then only need to set up synchronization pulse(s) with the belt to either buffer the converted images or provide automatic speed adjustment. Also if you forgo the crude image capture you can obviously up your resolution depending on your playback device.
I really like your Videos Ben.
They are the Inspiration for my channel. Thank You.
Automatic doorknob sanitizer? Prophetic!
the drill motor is actually an AC motor. there is a pulse width modulator that converts DC to AC in the drills.
Not sure if it was mentioned before but I know some used hard drives as spinning disks for their mechanical display projects.
Hate to say it, but I didn't think he'd get it working. Ben Heck is the bomb, but this is an exceedingly tricky build.
I have yet to see a home-made one that worked.
Foiled by 1920's technology. I think I will have to build one to see how hard it is.
Easiest way to keep your motors synchronized, is to use AC motors. Not universal motors (like in a drill) but proper AC motors. The speed is determined by the AC frequency, and by the windings of the motor. Once tuned, it should keep synchronized.
First televisions might use power for image stabilization. Look, in America we have 60 Hz, so television is 30 frames / sec. Europe has 50 Hz, that makes 25 frames / sec.
The used motors in mechanical TVs are for sure not low-power DC 12V or so, but more direct from power net. Because it makes circuitry easier with AC motor. (The old LP player or tape deck uses AC motor for drive)
The Nipkow cameras don't use light source. It's more sensor behind wheel. You can see it as "reversed" dia projector, in light-thight black box.
A mechanical TV has neon tube for light, or just strong bulb for light. Technically, it's projector TV.
You can create a really simple PLL-PWM controller for the second motor with an optical switch on each disk and a single XNOR gate. Yes, really! They will be ~90degree phase shifted, which is fairly simple to fix by displacing the sensors.
I think you should revisit this and use a pair of AC synchronous motors wired in parallel for the transmit and receive disks. If the mounting of one of the motors allows it to be rotated, you shouldn't even need any need any fancy electronics to adjust the phase.
Hall effect sensor, permanent magnet and a micro controller to stabilize the timing. The pulse may be transmitted via infrared led.
I find it interesting when Ben says things like he didn't want to use optos and micro controllers because he was trying to keep it simple. I'm like, "Why not? You do that stuff all the time?!"
+DoItYourselfMusician IMHO Its a "mechanical" TV, so they must keep electronics as simple as possible.
Wow I had an Old Canadian made "Supposed Pure Class A" car amplifier, a Blade Technologies M252 that I later modified into an M502 with help from someone with access to documents from Blades original Diagrams made for the M502 which shared the M252 board! It took a while, but he gave me specific part numbers and locations, the Toroid needed modified, either way the Amplifier used a weird system and had a 555 timer for the "Output Section"! Either way they claimed it was pure Class A, but it used NPN and PNP transistors for the Amplification which is technically Class A/B, Class D uses all NPN, but instead of the standard way of controlling the A/C "output" they used a 555 timer and a few other components, the amplifier was not even PWM supplied!
It had to have a 60mm Cooling fan internally just to be able to operate continuously and I had to install the controller diode, switching mosfet and thermal sensor! It took a few weeks, especially since I had to wait while he snuck into the secret room digging for documents and emailing me the part numbers and locations! But it was the funnest thing I have ever attempted and completed! Still that timer always brings to mind that Blade Amplifier! I love this channel, you guys do awesome stuff!
Yeah, the difficulty/complexity combined with the lackluster (to put it mildly) display resolution is why mechanical TVs never progressed beyond the fair/exhibition models. [of course it probably didn't help that they were also a faint, virtua boy-esque red.]
That having been said, I'd definitely like to see you revisit this to see if you can make it work. The attempt was interesting, and I'll admit to a fascination with old, esoteric technologies like this.
I'm really sorry this didn't work out, please do revisit this! I can't really say what to do differently as I am a mechanical engineer, not an electrical engineer :P
ZOMG!!! Zelda's shirt! Gadget is so fitting for this show! You all are essentially Gadgets/MacGyvers. :D
Great attempt, however a complete "compact as possible using state of the art components" to give the clearest picture possible (i mean really really clear, that you could see pointy corners of a square) would be awesome. There you have a 10x10x10 inch box with spinning wheels projecting an image on screen would be an awesome centerpiece!!!
Imagine if this tech had gone all the way, what would we have eventually ended up with in modern times had they not let go?
very good project
Ben, love your show. Your staff is awesome. Theres only one thing to be done. With all due respect, shave your head.
+Demetrius Coutinho
thats what ive been thinking hahaha.
his hair makes him look old.
The internals from an old hard drive may be a good alternative to the vinyl record & drill motor.
There is a two pole synchronous motor in some orange squeezer that turn at high speed and always at the same speed
What if both motors were AC, and used an external reference common to both rather than trying to link them? The old mechanical television systems did that; the only link between the transmitter and the receiver was the image data. They used the 50Hz frequency of the UK's electric power system as the reference. By the way, early US mechanical television experiments also featured someone named Felix...
You could make a signal sort of like 5v p-p pulses for the light signal and a 12v p-p signal for each revolution, then set up an op-amp to comparatively peak-detect the 12v signal and adjust the receiver disc speed untill the p-p signal from that matches and the light can be flickered on and off once the wheel is up to speed then it should be somewhat in sync.
I wish i could come to your workshop and show you how things are dome
Use brushless motors with ESCs. sync the discs' speeds and phases using optical sensors on the edges of the discs, a couple of PID controllers on an arduino using the servo library.
Or even better, implement the PID controllers entirely with op-amps.
you guys might want to put something in the title so I don't watch a 36 min video for something that doesn't work
Well it’s a very very very complicated project because of those highly precision synchronizations being required,so i am not surprised about this failure,great attempt, trough.
Ben, to compensate the disk speed you need to make more holes,or, bigger holes, and stronger light. BTW to get 60 frames per second you need at least 3600 rpm, doesn't seem a lot but for a old vinyl yes.
My bet is that the original mechanical tv used something like selsyn or synchro motor. And i would probably used ambient light for the "camera" and put the photodiode behind the disc with some lens or light diffuser.
revisit using stepper motors. that should make syncing easier (just an additional signal in parallel to the light level signal
I have a question about the motor control. Why not change the duty cycle of the PWM instead of the frequency? It allows for the output voltage to be a little bit more even. Using square waves seems like it would produce an uneven voltage output that varies a lot, depending on the voltage smoothing method used.
Or...wild idea here: buy an electronic speed controller.
Could try a single motor between the two records - as it spins in one direction, it would then turn both of the records in the other direction at the same speed...
I pretty much knew this was going to happen, and I'm pretty surprised someone as knowledgeable as ben didn't think this far into it. There are really 2 and a half main concerns with a mechanical TV.
One is a light pickup that can pickup enough light variances. This started out bad with the choice of parts and went to worse when you went digital.
The second is the synching of the 2 wheels. CRT TVs probably just started the dot where the signal picks up on the screen thanks to magnets (how do they work?), so I would be interested in hearing about how the mechanical TVs did it. Unfortunately rubber belts and luck are not going to do it.
The 1/2 would be the light source used on the display. I believe the original still used an electron gun, but no magnets? It still shot onto a phosphorus screen. Either Way you really should look at a strong controllable dot and for authenticity sake, a phosphorus display since it will probably best handle the need for a persistent display.
Anyways, a serious project and I think you guys should attempt it with a bigger budget and schedule. You never see anyone else attempting it these days so it is well worth it IMO.
Ben, could you make a dsi or dsi xl into a good gaming device for a future episode. I have a dsi xl i don't really like or use that I would like to turn into a good gaming machine like a handheld pc. Please do this idea
Revisit it. Revisit it. I didn't know mechanical televisions exist until 3 days ago. I want to see this push to its limit.Modern Marvels has shown a design on failed inventions. Particularly having both disks aligned and planted onto a single axle would make an easier initial build to scan a project a proper image.
just proves how genius
John Logie Baird really was, to give up in this day of age...wow just wow
Use AC Synchronous motors. The rotation and speed is frequency and phase dependent. They should be cheaper than Synchro Servo solution which would be the ultimate solution to make sure everything in synch. Using Synchronous motors you can vary speed by varying frequency and fine tune using phase shifting.
Revisit please!
Why not use rotary encoders to keep track of the position of the discs?
I am kind of dissapointed that you didn't finish it or give it more time, but whatever I guess you are too busy with more interresting stuff.
oh oh felix do a gentoo install :-D that'll be fun to watch :-D
The guy who installs fedora is a ventriloquist???
You need to add some sort of PLL to sync the two discs :)
I'd love to see it revisited!
please finish this project it's very interesting
Can you make it un HD? xD
I like the felix corner !! Don't forget Debian 👍🏻
how about two synchronous AC motors, or two oscillating fan motors?
+nrdesign1991 Synchronous motors are a good idea. Speed is easy to adjust by varying frequency. You could fine tune between two motors by varying the phase being supplied to the two motors.
are you kidding. coolest idea you guys have done in a while and you quit?
Yes, please try this agen!
Thank god I watch these with a speed ratio set to 1.5: wasted 1.5 less time :-)
We would love to see you make a portable console out of the Wii U gamepad.
i have thought about at-lease 5 ways to do this... its much easier using just the bare principle and you own creativity...much more rewarding
Would you build a capacitor that generates power from the wind for me? Charges would transfer to plates as they are pushed through by the wind. I would like to see you try this and see what you come up with.
when the message came down I was like - "what all of this for this project incomplete message"....man have to give 10 bucks to my friend....he bet that the project was waste....I was actually gonna bet for 20..thank God..I would be ruined...
Yeahhhhh, kinda knew that wasn't going to work...