CRT Archeology: Mystery Toshiba display (GBC MV-10A)

[@ntsecrets]

I just realized why I bet they used a shrunken pic on a larger crt. I bet it was to make use of the flattest part of it so there was no distortion at the corners since distance in the ultrasound image was critical.

[@dh2032]

and black and white screen, so there is a dot-screen mask? and going to an optical film camera anyway, and that most have it with lens optics too; the full screen was so large all ready, so idealy a smaller CRT might be better? but may not have exsisted, and if did, there sosable not ruged and sell biuld for left 24/7 everyday for years, the cheaply available sercurity monoyor where, and being ready market sellers, and good enuth is good enuth they just when the readyly available cheaper option than something made in house

[@Telewaifus]

GBC is "Gian Bruto Castelfranchi", it was an italian company and they had a division overseas. Usually they sold rebranded TVs and monitors, their main business was sold spare parts btw.

[@Telewaifus]

Pretty sure that the bezel had the purpose to mount a camera to take pics of the screen, like some scopes in the 60's and 70's

[@JessicaFEREM]

back when screenshots were shots of the screen

[@BrianHG.Ocean.Fitness]

@1:03:15, the 60hz bend you see might not be EMF, but, an actual magnetic field coming from the monitor's mains transformer interfering with the deflection on the CRT. Otherwise, it may be a dying decoupling cap for the yoke's deflection driver IC's power supply.

[@いつもの通りすがりの猫]

To avoid the effects of the magnetic field generated by the monitor's main power transformer, the transformer is positioned at approximately 45 degree angle.

[@graemezimmer604]

Yeah, but it was virtually impossible to completely eliminate the Hum Bar. The other trick was to put a band of copper tape around the outside of the transformer to short out any external field.

[@graemezimmer604]

And that "60hz bend" was known as a "Hum Bar".

[@Redlynx_X]

My assumption is that Toshiba used GBC as a monitor supplier for their medical devices. They resprayed already existing monitors to beige to match the rest of Toshiba's equipment.

[@ScottGrammer]

7:04 Those are SO-239 connectors, which mate with [EDIT]PL-259 plugs. Also called "UHF" connectors, despite being totally unsuitable for use much above 100MHz.

[@adagioleopard6415]

PL-259

[@ScottGrammer]

@@adagioleopard6415 Yes, you're right. I referred to my old 1976 ARRL handbook and found the plug referred to as a "PL-259," as well as an "83-1SP."

[@tr0gd0r04-z1l]

I think when they were created, 100MHz would have been considered "UHF" :)

[@pete3897]

@@tr0gd0r04-z1l Even back then, UHF started at 300Mhz :)

[@ScottGrammer]

@@tr0gd0r04-z1l Could be!

[@diskettenfett3161]

Adrian's Analog Basement - Great video, I really enjoy these monitor shenanigans, not many retro computing enthusiasts actually get into that topic. :)

[@AsherJohnson-k1i]

Please Adrian change your channel name to something like Adrian’s digital & analog basement or Adrian’s analog basement

[@Muz-2]

Make a third channel called Adrian’s analog basement. Also I was literally thinking about commenting that on a crt video yesterday!

[@AsherJohnson-k1i]

Yes

[@herrbonk3635]

@@AsherJohnson-k1i Adrian’s electronics basement?

[@AsherJohnson-k1i]

@diskettenfett3161 maybe

[@tankgrrl]

DHEW was the Dept of Health, Education and Welfare, the predecessor to HHS and defunct in 1979 when Education was split off on its own.

[@adriansdigitalbasement]

Hmm why do you think a video monitor might have that marking on it? (Even the non medical one had that in the photos)

[@talon262]

@@adriansdigitalbasement FDA Rule 21 Subchapter J (marked here as a DHEW [now DHHS] rule; the FDA was/is under DHEW/DHHS) has to do with regulating radiological emissions from electronic equipment.

[@timmooney7528]

@@adriansdigitalbasement 21 CFR Subchapter J focuses on Radiological Health and includes regulations related to electronic products that emit radiation. Whereas FCC covers RF interference, my guess is DHHS and DHEW covers human safety

[@wbfaulk]

Do you suppose "CER" is an old term for what we know now as "CFR", or was it a typo? I'm guessing the latter, which is weird.

[@tankgrrl]

@@adriansdigitalbasement I imagine this monitor was sold as a part of or add-on for the scanner. So being sold for use in a medical environment, it would be considered medical equipment.

[@BrianHG.Ocean.Fitness]

@1:06:00, no, a DC restoration circuit supposed to correct and regulate a perfect black level. The reason for the DC restoration circuit is that the RCA composite video source usually has a series cap when driving the video output so the on the monitor side where there is a 75ohm load to GND, minimal current is applied to that resistor. The DC restoration supposed to internally in the monitor clamp a reference black level to the video's black reference just after every H-Sync (known as the H-sync back porch). The black level issues you have been observing on cheap monitors come from either a poor DC restoration circuit design, or more likely poor regulation of the monitor's HV B+ output. I have in the past solved such dropping black levels by strategically adding a high voltage zener diode to one of the lower voltage taps on the flyback, completely elimination that shift in brightness at the expense of having the monitor's flyback transistor continuously working a little extra hard.

[@paulstubbs7678]

Thanks was just thinking up a reply on DC restoration, glad you beat me to it. I've bumper into so many cheap TV's that have no DC restoration, where the brightness is forever pumping as the scene changes - all to save a few cents. Yuk.

[@graemezimmer604]

Yes, DC Restoration was intended to fix drifting in the RF Detector, when the "Black Level" moved due to AGC clamping problems..

[@stevebabiak6997]

CRT pro here: 6:27 DHEW rule 21 CFR sub chapter J is the federal X-Ray standards for CRTs. CFR = Code of Federal Regulations BTW - FCC regulations on interference emissions from electronic devices didn’t come into play until sometime in the 1980s

[@seritools]

1:02:44 the non-leaking cap is one order of magnitude _out_ of spec (88.8 Ohm vs 8.5 Ohm in the table), so good to have swapped them anyways!

[@mlongval]

Had someone told me I would watch with rapt attention a video about 45 year old analog tech I would have laughed. You sir are a master teacher and storyteller. Cheers from Canada!

[@tonycosta3302]

I love seeing hand drawn circuit boards. Good memories from childhood when we’d get copper coated boards from Radio Shack and resist pens / rub down film to make them for projects.

[@Clavichordist]

A friend of my cousin used to repair monitors such as this for HP back in the day when he and my cousin worked for HP's medical equipment division. When HP sold off that division to Phillips, he had a lucrative contract maintaining the monitors for remaining customers until they retired their equipment for modern equipment.

[@adamwhite2364]

In regards to your closing comments, Adrian, I'm pretty sure we're all here to see the repairs, so anything you think anybody might find interesting, definitely post it to one of your channels!

[@Ashnurazg]

My first guess was that this monitor was probably used in a hospital like a heart rate monitor. That instantly came into my mind when I heard that it's a medical device. But after you showed that the bezel was probably for mounting a camera for a ultrasound scanner that sounds perfectly makes sense too.

[@TrinomCZ]

That turn-off dot was very common on many B&W TVs back in a day.

[@Drew-Dastardly]

Yes I remember in UK 1970s when the BBC daily broadcast ended and played God Save the Queen, I would switch the TV off and get that bright white dot. It was a failure of a diode (possibly even a valve/tube rather than a silicon or germanium diode) to deflect the beam at switch off.

[@ValuedTeamMember]

Yeah. I'm old school and and slightly turned-on with that turn-off dot. I don't mean to make "light" of it. Although it does put the spot-light on that issue. I'm just beaming with excitement that we're even talking about it. Just saying

[@SilverXTikal]

When I got my own first TV as a kid in the 90s it was some B&W 15 inch tv. I loved the thing mostly how it had no Pixels compared to the color TVs. Played all my PS1 and SEGA games on it. My favorite part was turning it off and seeing the extremely bright dot glow for awhile after I turned the TV on and off after letting it charge up

[@frankfix247]

I once had a Barco Graphics (an enormous beast of a CRT projector) back in the day that suffered from this issue. Had to replace the green tube because of dot burn-in and got sent a circuit board in addition that I solder to some points where the focus-adjustment knobs were located. That eliminated the turn-off dots completely.

[@Drew-Dastardly]

@@SilverXTikal This was bad and fecked up your CRT. It was deinitely eliminated when colour TVs became a thing. But could also be a fault.

[@dafoomie]

There were a fair amount of companies modifying regular off the shelf TV's for medical devices until the big manufacturers entered the market. I have a Sony KV-1311CR from the mid 80s that was modified into a display for an arthroscope.

[@AntoineWG]

It probably wasn't laying on its side, but was probably placed right next to another piece of equipment and the feet provided space for airflow.

[@rarbiart]

7:10 those jacks are PL258/PL259. Literally a 4mm banana jack with shielding. I saw setups using bare 4mm jacks plus crocodiles for GND to feed signals.

[@m1geo]

The sockets are SO239. The plugs are PL259.

[@dglcomputers1498]

​@m1geo Also called UHF connectors, though they are useless for UHF use. They came around before UHF was really a thing, so you can forgive the naming. Used a lot on VHF wireless microphone systems.

[@Qyonek]

Are you sure? PL258 is 50 Ohm. Is this monitor connector 50 Ohm too?

[@zaprodk]

@@Qyonek See the video termination switch. 50 Ohms.

[@paulstubbs7678]

In the early days of video, PL259 plugs were the standard, this moved to BNC on pro gear, with domestic quickly switching to RCA to save a few cents. I always prefered BNC for video, so you didn't get the video and audio leads mixed up.

[@alfonsotoledo8009]

You're becoming my favorite crt channel, despite not being the main topic of it😅

[@kurtiunlisted8589]

The blue ones would look great on an Altair

[@volvo09]

Yeah that would fit nicely on an Altair

[@heikovanderlaar3780]

"Who painted this beige?" I mean, who doesn't paint their electronics beige?

[@GrumpyOldGit-zk1kw]

Well I painted a beige BBC B 3.5" drive black to match my Spectrum 128 and Disciple interface. 🙂

[@jyvben1520]

certainly for medical system, the blue would stand out, the beige blends in

[@tookitogo]

@@jyvben1520I don’t think it’s about blending in. It’s about showing stains that would not be as obvious on dark colors.

[@ValuedTeamMember]

Funny. I was thinking who painted that (two tone) Blue? It may be the same reason a company will paint their "rental trailers or equip" some gosh awful bright orange or green etc. EZ spotting and to dissuade (yes I said dissuade) folks from stealing them. I just think that's a little nasty. Which ironically is what my last GF told me before she finally left. That's just my 8 cents ( inflation )

[@cpm1003]

We still have a little B&W security monitor in the back of a storage closet at work, along with a camera and 24 hour VCR. It hasn't been used in 25 years, and I'd guess it all dates to the mid 80s.

[@PixelatedH2O]

As someone who has had countless numbers of medical scans done, I could immediately tell what it was.

[@lolpie24]

The type of "peel apart" Polaroid film you are referring to is polaroid type 100 "packfilm" and its derivates. No longer made, this was the second major generation of polaroid film before the square framed "integral" SX-70 and 600 film. Polaroid had tons of films made for industrial applications and multiple generations of technology lived in parallel. A lot of oscilloscopes, Gel cameras etc used packfilm for its ease of use and ability to be xeroxed easily (compatible integral cameras were made too but less popular) also in rotation was the much larger and one shot type 54 which used the graphlex 4in x 5in standard, and for instant X ray applications the polaroid 8 x 10 system. This truly was Polaroids bread and butter, even more than their domestic uses.

[@graemezimmer604]

Yes, I went through hundreds of packs of Polaroid Film in the 70's, documenting the peformance of long-line video circuits for the telephone company.

[@KB0OTY]

That connector is a SO-239. And you're right, it's still used for RF connections with CB and Ham radio stuff.

[@torbar9603]

For the gap between the bezel and the case (or the tube and the bezel or both) just get a thin strip of foam tape and put it around the edge. It will fill the gap seal it so stuff does not go in and also add a bit of cushion for movement.

[@jjock3239]

My daughter is a bio-med engineer, and it is a common thing for hospitals where she works, to put those extremely expensive connectors on equipment that is used in special locations.

[@JoeMcGuire]

Ohh man, the old peel apart film!! Fun fact - the part you pulled off could be used as a negative in some occasions, mostly with the black and white though. I wish the stuff was still around because it was truly fantastic film.

[@ReTrace1]

Yes! More digging into CRT stuff

[@ChristopherHailey]

I remember we had a Dunn Instruments device that had a CRT and a Polaroid camera that could give you color 8x10 pictures. It was quite a process to get a hardcopy!

[@GaRbAllZ]

The connectors on the back are SO239, their male counter is a PL259. They are used extensively in HAM and CB radio.

[@twocvbloke]

A quick google (yeah, DDG just doesn't give the results I want), I found two ultrasound machines from the 70s called "Picker International" (turns out they were on the same ob-ultrasound website), and they both depict CRT monitors (not identical, but very similar to this one) placed on their side, so possibly this was a part of a baby-botherer machine... :)

[@horusfalcon]

The numeric designator for those connectors is PL-259. It is frequently called a "UHF connector". You do find some interesting toys, man! 😁

[@tekvax01]

The video input jacks are UHF PL and SO connectors (The PL259 is the male connector and the SO239 is the female connector.)

[@messmer777]

Hospitals have engineering departments and it is def possible that that thing was customized by hospital staff. That big honking plug was on every piece of hospital equipment even when I was working in hospitals 20 years ago.

[@Mal-u-Envy]

You can get paint matched at home Depot or Lowe's to the blue paint and then repaint the outside that color

[@maedero05]

Love the recent crt monitor special thrill fixing ! Flat-screen, doesn't have this crt becoming very rare today !

[@Ben-says-you-are-AWESOME]

I wonder if the CRT was changed from the original stock one in order to get a sharper image, or for some other image quality related reason to meet Toshiba's specification. It would be interesting to investigate the CRT type number to see if there's something special about it.

[@tekvax01]

If I'm not mistaken, the front black bezel on this monitor may be for a Polaroid camera to take pictures of the images, indicating that this was a medical monitor for some imaging equipment.

[@scarlettekk]

Did you watch the video lol?? he comes to this conclusion immediately

[@NaoPb]

I would be all for another video of this. And if the power switch is unobtainium or too expensive, maybe a different switch with a little light in it would be nice, since the monitor doesn't have a power light of its own,

[@dhpbear2]

47:33 - Tech Tip: a banana plug will fit into those video connectors.

[@jamesbaker7158]

These type of monitors were also used in television control rooms for broadcast television.

[@xenocide2121]

it was probably for photographing your baby so you could get a picture to take home of the ultrasound.

[@TheDefpom]

Those connectors are called SO-239, the matching plugs are PL-259

[@SonjaWeygand]

i would try some solvent on the upper paint layer, if you're lucky the paint beneath is baked powder paint that wont solve.Powder paint is often used on metal chassis.

[@jdebultra]

Just bring the top cover into a Sherwin Williams and they can match that color using a computer and make you a quart of something durable. Just clean and sand it...or not lol. Cool little monitor.

[@noland65]

> "Back in the day, we didn't have storage oscilloscopes" But there were dark-trace CRTs (AKA Skiatrons), which were used kind of in this way. (Dark-trace CRTs, displaying dark content on bright background, were hard to clear, which was also their Achilles-heel in their original planned for application as TV screens, as developed by the BBC just before WWII. But they found an application for radar and for oscilloscopes.)

[@jabbawok944]

Radwell are legit. We use them all the time at work. If they say they have it then they do somewhere. They’re very expensive, but they guarantee everything they sell.

[@Jody_VE5SAR]

With the sliding green window mechanism, that mechanically-indicating pushbutton latching switch is pretty cool. I searched for quite a while, and can't find any current makers of anything like that... It'd be great if you found one!

[@adriansdigitalbasement]

@@Jody_VE5SAR thanks for looking and too bad. it was surely an off the shelf part back then but perhaps it hasn't been used in 40 years so the supplier is long gone.

[@chadhartsees]

I assumed Green would be on and it would slide to Red for off, not black. So that was interesting!

[@Ghozer]

I don't think anything slid, I think it was more a depth thing, when the switch is pushed in, the front window would have been right up against the green, making it visible, when it's turned off, it's 'popped out' and darker and the 'green' further away from the front, and not as visible, have seen MANY do it this way, and sometimes coupled with a light behind the paper to make it more obvious

[@hyperturbotechnomike]

Maybe it can be repaired. A piece of small clear plastic can be cut from a CD or cassette case if nothing else is available.

[@ickipoo]

They were very common in the era. They have a name, but I cannot remember it. Is there a patent number anywhere on the switch? The way I remember them working is the colored bit pushes the black shutters aside when the button is pressed in.

[@jeromethiel4323]

As soon as i saw that plastic bezel, that looks like it could have a cover i was thinking industrial display of some sort. Many of those, even today with non-CRT displays in them have waterproof covers to try and minimize environmental damage. But it seems from the comments below that it is some sort of medical display. Which is also pretty cool!

[@FireballXL55]

Original coil mounted on the side PCB is a linearity for H deflection, it is set by adjusting it to max width then turning so left side starts to compress. The vertical deflection ic is probably a TDA1170.

[@8antipode9]

I believe your camera is focusing on the big animated pixel display behind you. Great video as always, BTW.

[@lindoran]

DHEW stands for department of healthcare education and welfare. Superseded by department of education, department of health and human services, and the FDA in 1979

[@lindoran]

I might be wrong about the FDA. But -- but it services a lot of the same overview

[@adriansdigitalbasement]

Ahhh -- interesting. The non medical version had that on it too, I wonder why the DHEW had anything to do with display monitors?

[@lindoran]

@@adriansdigitalbasement perhaps these monitors are for use in medical applications? Specifically speaking some kind of display device would still need to be approved for hospital use today -- perhaps those requirements were around in the late 70s my father was a GE medical systems engineer at least as far back as the 70s I can ask him tomorrow

[@TheErador]

​@@lindoranyeah but GBC were probably making these for cctv/surveillance purposes according to their logo on the sticker on the back.

[@chadhartsees]

@@adriansdigitalbasement Maybe the casing and electronics had to be protected enough from splatter or had to be able to be wiped down and sanitized easily in a way that textured plastic wouldn't hold up, etc. Or the metal case reduced the possibility for interference?

[@chadhartsees]

The picture is pretty bright, isn't it? High hours, but I imagine the brightness was tuned down because it was going to be in a completely dark environment and they didn't want to overexpose the Instamatic film.

[@Zeem4]

Instant film. "Instamatic" was normal film that needed sending off for development, only with Kodak's novel development that it was housed in an instant-loading cartridge so you didn't need to fiddle about threading into the camera or rewinding it when finished.

[@GothGuy885]

the Monitor looks like something from the Max Headroom movie picturing you hooking it to a computer and Max suddenly appears making funny commentary about your channel

[@The1RandomFool]

I find it rather interesting that so many mods were done to this monitor instead of just making a new variant. Probably was still cheaper to just mod the existing variant. I can't imagine that a lot of the modded ones were sold.

[@moonrock41]

Adrian, it's interesting how your opinion of this display's "haphazard" construction improved as you completed your examination, despite the criticisms you made at the end of the video. I'm particularly impressed by how good the screen looks for its age, but maybe it wasn't used very much. I'd guess there are relatively few decent CRT displays like this one left in the world.

[@tigheklory]

A ground isolation plug isn't really going to do anything as common and earth ground are bonded in the breaker panel in the USA. You should try and AC line filter on the power going into the monitor.

[@MrStephenschastain]

In our shop the connectors were always called TNC connectors. It was an upgrade from the BNC connectors. They were weatherproof and had less signal leakage. They could handle frequencies up to 12 Mhz.

[@pete3897]

PL/SO-259 you mean? TNC connectors are used on Linksys wireless APs for 2.4Ghz signals. Picture here: wikipedia.org/wiki/TNC_connector

[@tookitogo]

Those are absolutely not TNC connectors. TNC is literally a BNC with a thread instead of the bayonet, and both BNC and TNC are food for frequencies far beyond 12MHz.

[@graemezimmer604]

Definitely not a TNC connector. The TNC is like a threaded BNC connector. Perhaps you are thinking of the "miniature UHF" which is basically a smaller version of the UHF or SO259

[@bathesheba111]

Adrian Holmes! You need a pipe and spyglass for true authenticity. I love those old tear downs and repairs. Much more visual than software issues!

[@eagerestwolf]

That coax connector is called PL-259 in the CB world. It’s commonly used with RG58, RG59, or RG8X coax.

[@turbochardged]

that power switch was called a shadow switch.

[@MegaFonebone]

Adrian, you could really go down a rabbit hole of doing videos on the interesting modifications of computers and peripherals like this one that were used in the medical industry. For example, older electromyography/nerve conduction study machines were just modified oscilloscopes and later were portable computer or early laptop modifications with special peripherals for performing the medical tests. You may not be able to restore all the medical functionality due to proprietary OSs and ROMs, but even just a teardown to see what CPUs etc are under the hood would still be interesting. I, for one, would be interested in seeing more videos of this sort.

[@stphinkle]

I wonder if the full bright vs black levels were altered to make the contrast more acceptable for medical film transfer, maybe to not exceed film light levels and for opitmal contrast in the medical polaroids. I wondered if the camera needed the high and low light levels within a certain range and they altered the circuits to drive the CRT where the minimum and maximum will be in that range.

[@rgnglzrd]

Try Purple Power cleaner. It will strip spray enamel paint. Test on the inside first to ensure the blue won't come off.

[@draggonhedd]

Adrian, Dawn powerwash spray will remove spraypaint very easily, Spray it on, let it sit for a while, i think its like 20 minutes, spray it again, and use something plastic to scrape the now loose spraypaint off, leaving the original finish behind. Works on miniatures and RC stuff.

[@voltare2amstereo]

that connector on the back, is also used on older Umatic tape players (databits channel featured one the other day) can't have too many hours on it, there would be noticable wear difference in the phosphor between the used and unused sections...

[@freddydiazg]

GBC produced CCTV monitor and cameras, mostly for surveilance

[@sfeather7088]

At work, we dealt with Radwell one time when we were in a pinch. They were really good to deal with.

[@lordraptor11]

really took you till 4:04 to mention it was a toshiba when i noticed the brand in the beginning of the video, and im going to say it now 4:04 toshiba brand "medical systems" clearly it was build for the medical field most likely a monitor for some piece of hospital equipment.

[@Synthematix]

I have one 12" made by philips, its a white phosphor tube and at the front theres a slot to slide in coloured acetate sheets to change the screen colour, orange, green and blue, its pretty neat and has an awesome picture, very similar principle to the VECTREX tube yours was used in dentists to display x-rays

[@alfwok]

Cool to imagine people seeing their children for the first time on that monitor. Now we are playing Fat City on it 45 years later. Neat.

[@sythenelexia]

That connector is SO-239, its matching counterpart is PL-259 :)

[@jammi__]

"Scanning procedure" is making a scanning motion; moving steadily in one or two direction along a straight line. It's like using hand scanners, and what they provide is more like a flatbed scanner equivalent..

[@adagioleopard6415]

They're called SO239 and the mating connector is a PL259

[@KennethScharf]

Judging by the fact that the core of the width coil is all width coil is all the way out, I think the extra coil was wired in parallel with it to reduce the inductance more to get the width smaller.

[@graemezimmer604]

That ripple is called "Ringing". Was very common with simple CRT circuits.

[@fgaviator]

Nice archaeology adventure! "Adriana Jones exploring the Tube of Doom..." 😊

[@mrnmrn1]

The original blue color is most likely powder coating, that's why the white paint was unable to stick to it, because it is a plastic layer, not paint. Try different paint thinners, like some nitro thinner on the original blue coating on the inside. Powder coating is usually very tough, there's a good chance you can find a paint thinner that dissolves the white paint, but doesn't attack the original coating.

[@RobotnikPlays]

41:37 - Regarding the gap/wobbly bezel - you might have some luck with just putting some cardboard or something behind there, so it's got something to press against?

[@Joezip]

As someone who works for a medical device manufacturer that makes highly specialized, low volume devices, the stuff done to repurpose this monitor isn't a surprise. It may seem janky, but I bet at the time this was made, they were maybe making 20 of these a year. May also be a sign that this was a very early version of the device. Probably when volumes got up, they got specific models made for them.

[@StephenLaw-mp2jk]

A plastic cover should have been over the switch. This type of monitor was used with some medical imaging equipment. I had a friend who did field service for Toshiba. They bought these monitors from a third party and remanufactured them to meet their needs. They used them as a second monitor for ultrasound and another imaging product they produced. They also had a larger unit that was used in the operating room when they used ultrasound to do a needle biopsy.

[@KlodFather]

This looks like the display from an 80's Sonogram Machine. I had a system similar to this back many years ago and it had two displays on it made by Tektronics one XY and the other NTSC. This looks like a display from those early sonogram machines I have seen.

[@dhpbear2]

1:34 - The bezel looks like the ones on early Tektronix 'scopes. Not the ledge on the top where one could hook a 'scope camera' onto.

[@jeromethiel4323]

Oh, just had a second thought as to that bezel. That might have been there for a photographic camera attachment. We had those on some of the o-scopes we used in college. The o-scope was pure analog, and no way to easily record the results. We actually had a monster tube based o-scope that could be used to generate transistor characteristic curves. And since once you had it stable, the lines on the screen didn't move, you could clip a land instant camera to the o-scope and take a picture of the curves. You then had to wipe the developer on the film, and the fixer. But then, in a few seconds you had a nice permanent set of curves you could work with. And that monster o-scope had an attachment around the CRT very similar to that one that the camera latched onto.

[@jeromethiel4323]

And this was all covered in the video. Was still nice to know i was kinda right. ^-^

[@TheBakafish]

A lot of early EDM machines used similar displays to show the waveform of the eroding current. This is very likely a display for one of those, or similar heavy machinery.

[@adagioleopard6415]

Good 'ol leaded solder. No cracking.

[@njgriebel]

I love the august burns red background! Great music!

[@erikhaugan3043]

When I first saw that monitor, I found myself thinking it looked like it belonged on an electron microscope. That also had a requirement for taking pictures of what was being observed.

[@ASMRPoohbear]

Love these crt videos, so interesting

[@torelundqvist4957]

Try sticking some package tape on the paint and pull it off again. That sometimes works to remove the top layer.

[@rafaelgcpp]

The connectors are SO-239, also known as UHF connectors. (although they should not be used for UHF, as they have lots of loss on UHF 😀)

[@michaelturner4457]

I don't know why they're called UHF connectors, they were only really usable up to about 100MHz.

[@richardbrobeck2384]

Great little monitor ! I would love to see a video on the mod !

[@WilliamHostman]

Leaving the plastic bezel behind the metal provides a (minimum) of shock protection, as well as the flat surface. Do not forget: The whole television industry was full of half-assed efforts and stopgap measures. Hell, NTSC was a half-assed stopgap.

[@someguy2741]

I found the image but I don't know if I can share. Milestones in Ultrasound Diagnostics - Siemens Healthineers USA. There are a few pictures. There is one showing the monitor on its side on top of another substantial ultrasound machine. This is clearly a second monitor. But it did not have a camera on it. There is a matching monitor in the main machine that IS OSCILLISCOPE sized... so this second monitor was just a bezel to fake it so it would match the main monitor. The main monitor was built into the bookcase sized ultrasound machine.

[@hattree]

That DHEW thing is about radiation protection of electronics that emit radiation from the FDA.

[@helgew9008]

Judging by how the rubber feet have perfectly removed the paint, it may be worth a try to apply some gaffa tape and simply tearing the paint off, hoping that the paint will stick to the tape.