Conventional CRTs with electrostatic defection were also used in many small tabletop and portable TVs from the late 1940s through mid 1950s, where the screen was small enough (usually 7 inches) that the long neck wasn't that much of a problem. And the very first commercially produced TVs from before WWII had the tube facing vertically and used a mirror to reflect the image towards the front, because the tube was too long to put horizontally without making the TV cabinet ridiculously huge!

"Dr. D. Gabor at some university somewhere" (@9:20) is actually a nobel prize winner physicist, inventor of the hologram.

I love your reviews and enthusiasm Dave for the design and innovation! There wasn't a lot of great British innovation or manufacturing going on in 1980s in the electronics sector (if you put the early computer industry aside), and Sir Clive was definitely an innovator and pioneer. Although I did work for a small electronics company myself in the late 80s which did some pretty neat stuff for the secret services/police, "radionics" you might say, covert communications stuff. Sinclair was famous for doing things on the cheap and cutting corners both to make more money and offer things more cheaply. This would sometimes backfire though and end up costing him more in the long-run with failed products/recalls and replacements etc, and damage to his reputation. It happened on nearly every product he made, starting from his first transistor radios in 1960s (he bought faulty semiconductors and repaired them!). Likewise in some early ZX80's and 81's you see evidence like in the pocket TV there of touch-ups/repairs on the PCB's, component replacing, probably failed products returned, repaired, and resold as new..very naughty Sir Clive!! All of his products are functional (well mostly) but only to the minimum, and his designs are not very aesthetically pleasing (except the ZX Spectrum, or speccy as it's now fondly called). Although some might disagree with me there. The ZX81 was hideous design (I owned one). The keyboard was horrible that flat keyboard with no touch key resistance, and the thing got astonishingly hot very fast, as there was nowhere for heat to go, no heat sinks or vents or fans or anything!

Ben Krasnow has some great videos on how to deposit conductive, and other coatings on glass with a home built vacuum chamber. His latest video: DIY Custom LCD Awesome stuff!

Had one of these back in the day. I ran it off an external battery pack as the proper batteries were horribly expensive. Produced a surprisingly good image & was a good hand warmer in winter too! :-) Gotta love Sir Clive's funky retro gear.

After watching Ben Krasnow's videos, I'd guess that the Tin-oxide layer was transferred onto the glass by way of sputtering. Awesome video as usual, Dave. Thanks!

the horizontal scanning in tvs is usually produced by the high voltage transformer or flyback and is about 15.6 khz

Nice teardown. I remember fixing one of these when I was still at school. The traces on the underside of the top glass had been damaged, I assume from some physical trauma, so that they didn't make full contact with the compression connectors down to the mainboard. In the end I just patched them with silver loaded paint, but not before giving myself quite a whack from the Cockcroft ladder! It worked OK, but the picture quality was pretty poor, and of course tiny. I certainly didn't bother with getting a new battery when the original ran out. Polaroid made the battery IIRC, and it was amazingly thin, with a very similar contruction to modern LiPos

The best constructed product that Sinclair produced

Ah!! The old Tv-80! Picked one up myself a while ago in a broken state. Once I replaced all the pots for screen adjustments it was good as new. Couldn't test it without feeding it an RF signal from my (yes you guessed it) Sinclair Spectrum lol. As we have no analogue TV here anymore :-)

Hi Dave just a little tip: Put your clip-on mic on the side that is nearest to the camera. You'll get a more even sound level that way. Excellent video, thanx!

It occurred to me that this would have additional complexity in driving the CRT because the deflection angle for vertical (Field) isn't constant (like it is with straight-on CRTs) as you "aim" further down the line; you'd have to correct for that or your picture would keystone terribly! It'd be conceptually easier to do your lines vertically and draw the raster from left to right, but that's not how the TV signal is transmitted.

What is incredible for me, a new-generation child, is that the electrons can be deflected so accurately and quickly in the 1980. It's mind boggling. If my math is correct- 240pixels by 180pixels x 15image per second = 648000 electron deflections per second using magnetism!

Dave, my wife said she heard your voice so many times as I watched your vids on the morning having my breakfast, that she thought your were actually living somewhere in the house. I'd suggest you come by for a morning coffee if you ever make it to Bangkok one of these days

OMG this flat CRT screen is so beautiful

I find it cool that you mentioned bubble LED displays... I'm using one (a HP 7400 series 5 digit unit) in a college project, circa 1976. Cool vintage stuff.

With the dots hitting the phosphor probably at something like 45 degrees, the dots would be oval, the lens stretches those ovals back to dots without using the repeller, the angle would be shallower.

Someone at school had one of those. I got a Casio TV400 in the late 80s. Used to use this to watch Aussie soaps on the train home from work I remembered which cupboard it was in, so just went to grab it to see if it would still work. I flicked the power switch and it came on! WHAT?!?!? I haven't used the thing since I moved into this house in '99! The Kodak batteries are marked 08-99 and have not leaked. Seems to pick up my CCTV modulator and digital box modulator OK (no analogue TV here either), but there are three rows of dead pixels.

Hehe. "Sucked out the vacuum..." Sucked out the air and left a vacuum? Great video. Very enjoyable to see these offshoots of the crt technology.

I have been looking forward to watching this

Awesome teardown! Thanks for the video, I was really intrigued by the combination of innovative solutions to come up with this product. I'd really like to see it working though. Some dedicated reverse engineer hacker could maybe have a go at trying to input some custom video data to it.

very good explanation of a cool technology thanks dave!

Awesome video Dave. We need more people like Clive Sinclair. Even if not everything they invent and market become sucessful. Next, get an Amstrad Hifi and do a tear down on that. ;-)

Still have one of these, about 2 years ago I came across it at the back of a drawer, turned it on and it worked, no reception as analogue was off by then, just a raster. This is with the original battery, staggering! I also have a Casio TV-100, colour LCD pocket TV, that also still works with just a raster.

Love this channel, thanks dude!

I was working in Currys Electrical in the UK when these came out. We would get maybe one or two every now and then, which did sell but I doubt if for the whole time they were available we ever sold more than 10 in a year. They were quite a wonder to behold, great fun but... just not popular. GREAT VID Fascinating tear down

My grandmother worked for ferranti in England for years!

The line output transformer was responsible for EHT via the large overwind, and the yoke drive for the horizontal coil. It even ran some secondary supplies. They worked it hard. It also had a tiny loop of wire around the core which fed back to the power supply to sync the p/s transformer switching so that the two didn't run out of phase and do your head in with a dual 15khz swimming effect

About the transparent conductive coating: Ben Krasnow recently made a video about 'sputtering' tin oxide onto microscope slides. (Intro to sputtering (process to create clear, conductive coatings)) He also has videos about thermal evaporation, and using the transparent coatings to create LCD displays.

To "metalllize" surfaces with a thin layer of chosen metal, one uses a vacuum chamber where a small cup sits at the bottom. One places a few bits of a chosen metal in the cup. These metals in the cup is then exposed to a high voltage arc, which will melt the metals, and soon after that, it will vaporize the metals. Every exposed surface inside the vacuum chamber that is exposed directly to the molten metals in the cup down below, will be hit by these metal vapors. The metal vapors will cling to any exposed surface and stick to it. That will slowly build up layer after layer of the chosen metal. The longer exposure, the thicker the layers gets.

"Bobby Dazzler" I love the way you talk. That was indeed quite interesting. I wish you could get a replacement IC so we can see it in operation and scope out some signals.

Awesome mate.

10:24 haha it's trippy hearing your voice get louder/quieter when you face into the board vs. away acoustics son! great videos looking forward to getting more into hardware vs coding 14:20 "In this case 1400 volts" what haha going to watch that walton multiplier video next

Congrats on 100,000 subs

Hmm, could you vary the voltage on the repeller to determine the horizontal position of the dot on the screen and do away with one of the control electrode pairs? i.e. higher voltage gets accelerated into the phosphor earlier.

To answer your question @ 27:25. Yes the frequency of the flyback transformer is in sync with and drives the horizontal raster scan on a CRT television.

That's a very well drawn diagram!

So, I was on the TV80 page on Wikipedia, looking at the image gallery. "That looks like Dave's lab..." *youtube search eevblog TV80* yep, that's Dave's lab. Nice one :P

This unit would work in any country that used PAL broadcast transmission on the UHF band. At the time of release, the UK had almost exclusively switched to UHF TV broadcast and some countries dipped their toe in the water. In Australia (Melbourne, at least), SBS was eventually transmitting on UHF Channel 28 and community TV on UHF channel 31. This Sinclair unit should have been able to receive and display both of these broadcast channels.

TV power supplies synchronized to line scan frequency, were standard way back in the days of black and white vacuum tube TV's. That's were allot of the terms LOPT line output transistor, line output transformer, HOT horizontal output transistor, fly-back transformer originated.

Amazing !!! I have to think this as something like an 3d electron hologram, they though in the 3rd dimension. What material is that transparent tin oxide electrode?

I have one of these and the output on it is kind of funky. It almost looks like it's got a "underwater" effect. I've yet to take it apart and screw around with it, but if you happen to have any insight would be much appreciated.

Great video thanks for the teardown. Is that a serial number printed with silver metallic paint on the CRT tube? Interesting.....😁

I maybe mistaken but it look like the scan line would be vertically instead of the usual horizontal scanning ?

I have a intercom system with a similar flat CRT screen. The screen panel is slightly curved and there is no lens over the panel.

Ben Krasnow has been doing a series of videos on transparent electrodes. He shows how it is done when he makes his own LCD. Well worth watching.

Thx EEV! Shes a bobby dazzler for sure!

"Don't turn it on, take it apart!" Why not both?

It would be the perfect TV to watch while driving the Sinclair C5 eletric car.

Any interest in possibly trying to drive the crt perhaps with an FPGA? Since you have the full schematic it might not be too hard since that custom chip would mostly be tasked with the timing of decoding the PAL signal. If the sweeps are already being generated it could be as simple as driving a single pin with an D/A converter on a micro.

Geez that's just so cool it's only there was only a slightly bigger one then I might be able to use it whenever I build some kind of pit boy to put on my arm as a prop I can use to display to actually display stuff that would be awesome

It's actually referred to as magnetron sputtering, a form of PVD (physical vapor deposition).

Is it possible to get that ferranti IC from somewhere? I'm curious to see this thing working again...

Please could you give me the model of the video camera you use, it is great quality and I'd like to buy one.

Hello, Do you try to energize these things before tearing down? It would be nice to see them in action Thanks

I had a portable TV with a similar design in the early 90s

It's a pity Australia has just shut down their analogue TV services because it would have been nice to try to get this working again, not much point now unless you plan to start your own TV station.

Pretty cool! I was thinking during your whiteboard talk that the CRT seems similar to the one that Sony used in the early Watchmans, but then you went and mentioned it! haha From what I remember, I think the Sony used a curved phosphor screen instead of the deflector, but I'm not positive. I have one laying around here somewhere, I should find it and take a look.

Great Terdown dave Video below will be of interest all about Sinclair at 30 mins in it covers manufacture of this CRT they actually used a laser to cut the tube! Horizon - Clive Sinclair, the anatomy of an inventor 1989

had an 80's casio colour lcd pocket tv, the battery life on 4xaa was only a couple of hours and the resolution was very low

en.wikipedia.org/wiki/TV80 that must be YOUR bench, Dave... well done, thank you!

Fascinating flat CRT design. Those crazy Hungarians...

Do you think you could make screen work?

Sinclair Flat-screen pocket TV FTV1 1983 - 30th Anniversary 2013 These ones are on, but no pictures :(

are you fix it to work again??📺📺

Is it working? Can you show how it looks.

I'm kind of disappointed in the lack of content lately. What's going on Dave? I really do enjoy your videos and don't want them to stop.

what are the white and black things next to the multiplier?

i see the yolks aren't coils. how do tin panels accomplish deflecting the beam? It's not magnetic defection?

Definitely high on the Bobby Dazzler-scale

I have seen similar pocket TV's that have the phosphor screen at a slant so they don't have to use a repeller.

Is it actually a fresnel lens? I would have thought not -- better to use just a regular single-axis convex lens

nice drawings

They also have the Sony Watchman.

When Amstard taken Sinclair company down during 1984. married to each other and created PC.

Shame you didn't try to fix this last week! All of the analog signals are gone forever!

27:40 The switching power supply drives the line scanning- sounds utilitarian to me. But if this is so then the switching power supply can only operate at a single frequency and duty cycle? No versatility here then.

I'd love to see dave build a simple drive for the CRT and try re-purposing it for the geek factor, but that's probably too time consuming to be practical.

CRT mean? The Jack. The Tube 1984. Socket-ted, inside the Radio CRT looks beautiful...in the inside but outside looks good!

80's = vintage, HRMF! That was last month! :-)

This is so cool, i bought one of those back in the 80s. Loved it, shame it used those mental lithium battery packs.

Was this CRT design used for anything else apart from this?

Made to a surprisingly high standard of quality for a Sinclair product. I remember them as usually being really cheap and nasty (which was oddly almost part of their charm!)

They should use this technology today!

Any more dumpster diving??? in corporate building ? :)

CRO will need to be electrostatic, as the impedance of the coils used in EM deflection would massively limit the bandwidth. This is a shame as I wouldn't mind turning an old TV into a 26" triple beam CRO

This specifically used Polaroid Polapulse P500 batteries.

indium tin oxide?

I just bought one. I'm going to put a LCD & Raspberry Pi in.

Yay!

Ch 21 - 69 is standard UHF channel numbering

I want to see it work.

Dave you could get a battery out of a used Polaroid camera film pack

the uk only had 4 channels when this came out

Electric field deflection method is a lot faster than magnetic deflection.. However, tub e is complicated..

09:16 What about patent number US 4205252 A and US RE31558 E?!? Inventors Sir Clive and A Krause.

Hold on, this thing used disposable lithium batteries? non-standard?

Speaking of portable TVs, I believe Sega released one for their Game Gear in the early '90s. Probably wasn't the best since that system could only display 32 colours at a time.

how about switch it on?

instant like!!