After first putting a purple spot on a TV as a kid, I learned over time to massage the purity problems away with magnets. Just keep waving them around and turning them until the bad color has gone away.
I remember doing the same thing as a kid of 10 or 11. At first, I got scared that I broke the TV! Then I realized I could fix it by carefully moving the same magnet around to fix the spot. It felt pretty magical that you could affect the TV in this way. Now, I _think_ this is what the degauss circuit is supposed to do, and the TV my parents had from the late 70s just didn't have one. So likely this wouldn't be fixed by manual de-gauss with a permanent magnet (though maybe worth a try?) Knowing this, I suspect there's something wrong with some of the magnets in the TV designed to correct any geometry problems. The fact that the distortion is symmetric only adds evidence. As someone else said in another comment, It's _possible_ that adding a permanent magnet somewhere in the TV can correct the impurity.
Yeah just not knowing on this TV what caused this problem - -definitely the aperture grill can get physically warped which can also cause purity issues versus just residual magnetism imparted from an external source. Some other comments mentioned that if the TV was stored near strong magnet for a long time, it causes the warpage.
@@adriansdigitalbasement2 at 27:21 .. the tube has that metal shield that goes all the way up (pretty close to the speaker magnet).. and also go under the tube... in the area where the impurity is....... my best guess.... that shield becomes magnetized... by the TV Speaker.. or by an external magnetic source.... take off that metal shield for a moment... and see if the impurities is still there ...
@@adriansdigitalbasement2 Well you know what we never had a Sony until I was old enough to know better. Before the Sony was the ubiquitous Zenith made from half a forest of lumber which oddly we got in around 1987 when those TVs were already way past their prime, but it was a brand new TV.
@@adriansdigitalbasement2 Adrian, a lighting nearby can cause that (it happened to a TV I have) or simple because the TV was close to some source of magnetism. That is not a problem with the CRT. Technician use a tool that is formed by a round demagnetizing device, that is simply a large coil connected to mains and pass it in front of the tube in circular motions. If you google it, I am sure you you find information about it.
I'm happy to see that the view rate of this channel is actually pretty high, some recent videos have 13k views, with this channel having 13k subs. Awesome!!
I made myself a degauss coil from a scavenged coil from an old monitor, Doubled it over to make a smaller loop and attached a plastic handle with a power switch to toggle the coil. I run an incandescent bulb in series to limit current, 40 or 60 watt depending on how strong I want for degauss. Works a treat and have fixed many blooms and blemishes in various CRT.
This was one of the first TVs I ever bought. Worked great for many years. Had a lot of game platforms hooked to it over the years starting with my Radio Shack color computer which was my first computer back in the early 80s.
You need a mirror on your bench. :). Lean it against the wall and point the crt at it and you can do the adjustments without having to keep peeking back and forth from the front and back. You’d probably be able to get the controls and display in the same camera shot as well. Love your stuff!
Hey Adrian, One way to fix the purity spots is with an degauss ring or wand. They are great at fixing spots where permanent magnets have been to close to the tube. PS. I really like the second channel, keep up the good work 👍
Agreed about the degaussing wand. Even in the mid to late 90s we would sometimes use them to clear up stubborn color smear issues on monitors that were auto degaussing.
I remember the TV repair guy coming over when I was a kid and using what looked like a small hoop with an AC conductor spiraled around it. He just plugged it straight into the wall and waved it around close to the screen in circular patterns. That apparently did the trick. It looked like something he'd made himself. Maybe you could do something like that to fix the magnetization?
Ah! You're thinking of a Degaussing Coil! They're pretty simple to make which is why the one you remember looked that way, cus he did make it. They basically just remove something that wraps around the base of the tube, wrap it up in either electrical tape or just something so they dont fry their hand (immediately) and hook up AC power to it. The reason I say immediately for frying their hand is because, well, live electricity and metal makes hot of course ;-)
The big professional degaussing coils you would find in the retail chain store repair areas was a degaussing coil like you describe, but it was mounted on a trolley. When turned on, the coil would rotate in a circle and you would put it near the TV and slowly roll the trolley away from the TV as it spun circles. There's absolutely no need for it to be that precise, so you can definitely do this by hand. But the issue that I'm seeing on this TV is probably well beyond fixable. At best, you could reduce the notability a bit, but it will likely always be there.
I've used permanent magnets to carefully nudge the mask until it's _just_ past what looks right and then the degaussing coil can bring it back. Easy to overdo it and end up worse than when you started. Otherwise, maybe the next video on this TV will include you making and using a high power degaussing wand?
I've fixed a CRT monitor with this same technique. I've used an electromagnet and a permanent magnet, I think the electromagnet works better for this purpose.
@@danielzulatodiasdemoraes2557 You can slowly pull an electromagnet away from the coloured area and "paint" the problem away. As @Matthew Ellisor stated, you do need to be careful or you end up making it worse. Back in the day, I had a degausing coil extracted from a dead monitor that I would use to repeatedly degaus selective parts of the tube. There is a bit of an art to it. Also take care with repurposed degaising coils. There should be a PTC thermistor with it. This is sometimes in the coil, and sometimes on the PCB or chassis. If you simply strap the coil across the mains without the PTC then it will probably get very hot very quickly and/or pop a fuse. "In most commercial equipment the current surge to the degaussing coil is regulated by a simple positive temperature coefficient (PTC) thermistor device, which initially has a low resistance but quickly changes to a high resistance due to the heating effect of the current flow. Such devices are designed for a one-off transition from cold to hot at power up; "experimenting" with the degauss effect by repeatedly switching the device on and off may cause this component to fail. The effect will also be weaker, since the PTC will not have had time to cool off. " Souce -> en.wikipedia.org/wiki/Degaussing#Color_cathode_ray_tubes
@@AndyHullMcPenguin I just use a neodymium magnet stuck to a drill bit. Run the drill, start close to the screen and you can pull the magnetized spots away as you pull the drill away. For really big spots you can just keep it close and running at top speed, just remember to pull it away before stopping the drill or you'll just remagnetize it.
@@AndyHullMcPenguin When I was still selling and doing Sony Warranty at my tv repairshop i would run into this Problem at times I still have a couple my commercially sold Degaussing coils .
I wouldn't recommend this, personally. It's more likely to cause more harm than good unless you really know what you're doing. In my experience, the problem here is likely permanent and nonfixable. At best you could reduce the problem somewhat, but it will never go away.
This TV just gave me a massive flashback to my childhood. It's just like the one my parents had but maybe theirs was a little bigger. I specifically remember the wood grain vents and the remote.
Wish my family had the money in the 80's for one of these. Still remember our Zenith floor mount jobby that had the VHF and UHF dials. Love the videos Adrian
@@misterkite My parents had one back in the 80’s all the way through to the early 2000’s - I think it was either a National or Philips brand. I remember we used it to pause during ads when we would record a movie or tv show.
Use the coil side of a weller soldering gun. Sweep the screen with the coil side (top) of soldering gun with the gun on of course. Also, check for loose wires that are near the neck of the tube.
For adjusting the RGB bias and drives it's best to use a pure greyscale pattern with no chroma signal at all on it, I'm sure your Tek generator does that.
You mentioned remotes were in their infancy around '82. That might be true for IR. I had a 70 or 71 Quasar that had a' clicker' sonic remote. Tuning forks/hammers that controlled the power/volume and channel. Loved it, except at night when my parents could clearly hear the clicks from their bedroom. A set of keys when you shook it could make the remote randomly do vol or Chan.
Two ideas: - Use an external High-Power degausser. Some TV repair shops have (had back in the days) external degaussing coils as the internal does not always have sufficient power to get rid of all harm that a magnet did. External can do. Or keep trying degaussing. - Trinitrons use a stripe pitch out of fine wires instead of holes etched into a solid material. These wires can vibrate and tangle into each others, this is why Trinitrons typically have these fine horizontal stabilisation stripes which you can clearly observe on stripe mask (Trinitiron, Diamondtron) PC monitors. But also the horizontal stripes cannot fully prevent this. A mechanical hit, not strong enough to damage anything, can tangle some stripes. Carefully hitting the TV can make this better - or worse But I would rather point to a stronger magnetic problem, judging from the pivoted degauss you did in the end, so keep degaussing, pivoting the screen around, or look for an external degausser.
We had this TV back in in the day 83-84 if my memory serves me well. It was located on my Father’s room! A few years later (86-87) he upgraded to a 19 inch Sharp CRT and gave me the Little Sony TV for my room! Boy I was a happy teenager when he gave me this TV. Sadly that lasted a couple of weeks because he disliked the picture on his new 19 inch Sharp TV. So one day I came from school and he exchanged the TV’s! Even though I got the 19 incher I liked that Sony better! The remote control face mas made of aluminun and every time the remote was dropped got dents on the lower corners!
Another cool CRT tv.Adrian you work a lot on CRTs so you need to have a mirror so you can see the screen while adjusting tv and etc its a must have for that. So the back if the tv is facing you
Adrian, we used to magnetize a long #2 Phillips screwdriver, and wave it in front of the screen to repair those magnetized portions of the screen like you have in the bottom left corner. Not sure if that will help in this case, but its worth a shot.
This brings back memories of my parents mid 80's 19" Sony Trinitron TV. It was a great TV. That futuristic silver and black plastic front contrasted by woodgrain on the sides...
As others have said, you could try running a magnet over the corner there with the purity issue. I had a trash picked compaq monitor as a kid that had this issue and managed to fix it using the magnet trick mentioned. Worth a try at least... Wish a magnet would fix the "purity problems" with my LG IPS monitor's red/ now purply white warping corners! :(
The purity issue might be the grill, but it's a chance it's just been heavily magnetized by being next to a speaker or something. You can try a stand-alone degausser which is much more powerful. They look like a big ring, generally cost about 30 bucks or so. It's a good tool to have if you are doing stuff like this anyway, and it might fix the issue. Make sure you watch a couple videos on how to do it correctly because it's possible to make it worse if you do it wrong.
I jumped from a tiny little B&W GE set to a Sony KV-1948R color set in 1983; it was like Technicolor on a television screen. Had nothing but Sony Trinis and rear projection LCD and Bravia LCD TVs until 2017; then I was beguiled by Samsung QLED. I hope Sony gets their Trinitron magic touch back into their flatscreen sets.
For that purity problem, you can try some magnets like a speaker or fridge magnets to help improve the picture. When I was little, I had A Philco CRT tv (still have it and still works) in my bedroom near a boombox. When the boombox was near the tv, the picture went nuts, like a rainbow. My dad fixed the tv with a smaller speaker, rotating the speaker further away from the CRT.
When I was a kid learning this stuff from my father, he had made a degousing coil by taking one from an older TV. Then Hooked it up to 120 volts. Then he would plug it in and turn the TV off then run the coil around the front of the screen a few times the unplug it before one of his children and I won't name names. (me) tried to play with it! I've used it many times and it would work great..
I love the woodgrain look. We had a huge TV in a wooden console. The thing weighed a ton. My parents bought it in the early 80s and kept it until about 2010.
Great to see a 1975-youngster was also stung and infected by the Electronics Exterior Design Mosquito, most likely as a child adoring the right stuff. Totally agreed. It's an excellent designed TV by Sony. They got it right pretty often from the 1970's (ELCaset and matching cassette exterior) and into the 2000's with HDD/DVD-recorders.
I just found one of these at my local dump this morning! Thanks for uploading this great overview! Going to do some testing this afternoon. Hopefully it powers up!
Regarding the purity problem, the mask is bent from strong magnetism, you could try to bend it back with a strong magnet (using the right polarity of the magnet or you'll make it worse), there is also a special tool tv repairshops used to flex and make the mask even/straight again. But if I remember it right Trinitron used strings, maybe they are just stuck together, a small hit might make the loose again?
Yeah there are those wires that run across the grill in the middle - but down at the bottom it seems odd. Makes sense they are deformed though, perhaps it was placed near a strong magnet for a long time which warped the wires.
Found a direct mention of this fault on these type of Sony TV's "Any nearby magnetic fields can cause it - speakers were a common source. CRT TV's have a deguass circuit that demagnetises the screen when you turn the set on from cold, these can fail - and require the posistor replacing. Applying an external deguassing field might be required to cure it, and these used to be a common part of n engineers tool kit. Last option is the purity needs setting up, but you MUST eliminate all other options first - a common cause on Sony Trinitron sets was the scan coils actually sliding back on the CRT neck (part of the setting up is sliding the coils backwards and forwards, then locking them in the optimum place)."
Philips were turning out aesthetically pleasing 14” crt in 84. I had a nice little silver one with my acorn electron hooked up to it. This is very nice looking though, like a halfway house between veneer and the metallic.
Concerning the colour purity, I've seen a degaussing coil used once to fix a monitor. That monitor had been damaged by a strong magnet, and the damage was greater than the monitor's internal degaussing circuit could repair. A family member came over with a stronger, rigid degaussing coil that used to be used by a TV repair man. He plugged it in and used it to restore the monitor. I was a kid at the time when this happened though. I'm not sure if the same solution would work with this television or not.
When I was young my sister bought her first TV. It wasn't a Sony, but a few months after she bought it, a similar issue arose. It turned out that the speakers of the little stereo she was using in an attempt to get better sound did not have shielded speakers, and the magnets screwed with the TV. I helped her take it to the repair shop and they literally used magnets to carefully pull the weird spots on the tv away. I was 10 when this happened, so it was 1990 or so? I thought it was fascinating. After that she moved her speakers to the corners of her room, not wanting to have to do that again, I guess.
I've got a Sony radio alarm clock that I bought to wake me up to do my paper round in the early 90's. I still use it today and it still works. It still has the "it's a Sony" sticker on the front.
The reason the UHF had screws is it came with a loop antenna that screwed to those. The di pole antenna was coax and screwed into the f connector for VHF
I used to repair CRT monitors in the late 90's and have fixed many a purity problem with a degaussing wand because sometimes the internal degaussing coil doesn't work as well as it should on the extremities.. if you don't have one then anything magnetic can help in a pinch but its easy to mess things up worse, so it's up to you whether you want to take the risk.
"Brown in texture" is what I heard. And I guffawed! After a rewind (why is that a thing for digital media?) and closed captons enabled, I realized I was sadly mistaken. "It's just brown and texture." Good content, as always!!!
Noticed that there is a metal shroud on the sides behind that CRT and I was wondering if it may have become magnetised. The degaussing coil is meant to fix the bias on the CRT, but is less helpful for nearby magnetised metal. As others have mentioned using a manual degauss process may help. If you still have trouble, check to see if the shroud may be magnetised with a magnetometer or by holding some non-magnetised ferrite metal near it to see if it attracts.
OCD kicks in big time when you start tweaking the convergence controls 😄. Tend to find random purity usues occur on weak tubes, especally if the flyback gain is increased too much to compensate for weaker tubes. Can't really beat a propper degausing wand though, cause those internal ones don't always cover the whole tube that great.
My guess is that this was sat next to and above unshielded speakers for a long time. Hence the purity problems on both bottom corners. You could try the magnet twirl to try and get it right, possibly even use a small magnet to affix permanently to adjust it. Trinitrons have always had great pictures.
That's a very cool Sony TV. Sony was considered a high-end brand back then. And the screen size is very unusual too. I have never seen a 12' color TV they are usually 13" about 99% of the time.
Way back long ago, I purchased one of the most expensive Sony Trinitron TV's. Despite it being a top model, the picture quality seemed to be flawed. If you had what was supposed to be a full red screen for instance, you would instead see about an inch worth of red colour on the left hand side, but the rest of the screen would be a pale pink. So I took the TV back panel off to have a look. This TV had a slide mechanism that allowed you to slide out the main board from under the CRT for servicing, and still power up the unit. Anyhow, I slid the board out and then I provided a red blank image to the TV. But now it was flawless. The whole screen was now bright red. WTF? Then, I slid the main board back to its proper place under the CRT. Now It was back to being a mostly pink screen again. WTF ? Then I figured it out. The CRT yoke was giving off suffice enough of a magnetic flux for it to be inserting about a volts worth of the horizontal sweep signal onto the +12 Vdc power line on the PCB. In the long run, this led to the flaw in the final CRT screen output. So I could see that this was going to be an easy fix. I connected a wire to GND, then wrapped it twice around the CRT Yoke, and then directed the signal that this wire was picking up from the Yoke, right back to the +12 Vdc power line, and did so via the use of an electrolytic capacitor. This of course then cancelled out the original problem.
I am having those same purity issues in the lower corners of a Sony PVM I picked up a couple years ago. I always assumed this was a permanent age issue. If you ever fix it update us all! Thanks again for another awesome video.
You may want to try adjusting the purity rings or the yoke itself, however, some of the trinitrons had some purity issues, the factory would slip purity magnets that looked like a piece of plastic about the size of a popsicle stick which had a small magnet at the end under the yoke windings...this was more for convergence, but helped with purity.. Also, a degaussing coil ,if you pass it all around the crt it would sometimes clean up the purity. The early trinitrons of the 80s always had those kind of issues with purity at the edges of the crt's, sometimes it's an issue with the shadow mask or even something on the chassis that's causing a magnetic field...even the built in degaussing coil could be causing that issue....there are quite a few things that may be attributed to that purity issue. I've actually taped a small weak magnetic near the affected area and it will clean up that problem, but , not always. Yes, that was an issue of that era sonys especially the smaller crt's, but, keep trying ....those models were gorgeous tvs and extremely well built, we'll never see that quality ever again in televisions.
If you don't have a regular degaussing loop, you can try a bulk tape eraser using a circular pattern. Even the back of a big Weller soldering gun will work.
I knew people growing up who left the "It's a Sony" sticker right on the corner of their TV and never took it off. I could never understand that! Of course now, if they still had that TV, it would be worth extra because of that sticker -- but still. Why leave it on a TV actively being used?!
@@adriansdigitalbasement2 I have seen a lot of equipment with that badge particularly left on it. I think lots of people did like it. I just wish Sony still made they so I could put them on some newer devices xD
That remote control is pretty much the same box design as the one that my SL-F1UB portable Betamax recorder kit came with (but obviously with very different buttons!), proper chunky thing... :)
My friend just let me borrow one of these! Watched Home Alone & Batman Returns vhs on it last night. The sound quality is amazing for such a small tv. Picture quality needs some adjusting here & there but overall a great vintage 📺
Adrian, If you look around the scan coils you might see some flexible plastic "sticks" for want of a better word. they are called permalloy sticks. They have a magnet on one end and an adhesive pad on the other. I suspect one of them has moved. Just in case you are wondering. the dual headphone jacks are very cleaver. One mutes the speaker, the other doesn't. So you can listen on earphones when your mum does the vacuuming or 2 of you can listen on headphones at night.
Oh I didn't know that little trick about the headphone jack. As for the monitor -- this type of distortion would come from magnetics right around the front of the CRT -- anything by the deflection yoke (like the little strips you mention)) would just cause mis-convergence in the corner which this TV doesn't have.
On larger envelope CRT's if they are stored on their sides, as opposed to their bases, the shadow mask can "buckle" under the force of gravity. The shadow mask is only pinned in the corners of the CRT envelope, so any changes to this arrangement (i.e. stored against its design constraints) damage can ensue. Having said that, this buckling has to be actioned over quite a long time, to make this happen. Maybe your example has been dropped and bent the shadow mask irrevocably. Else, if you have persistent magnetic contamination of the shadow mask (even smaller screen sizes) which is not down to physical impacts and abuse in storage, you'll need to manually get rid of it using a so-called "degaussing wand". Whether these sort of tools are available today, I don't know? Else, Trinitron CRT's can be a real "biatch" to keep the shadow mask "clean" i.e. raster purity. Again, on larger screens, we [at least we in the UK] used to deploy dedicated "magnetic buttons", in strategic spot places around the rear glass CRT envelope, to remove persistent magnetic distortions of the shadow mask. EDIT: If I had a £1 for every call out I had to someone with a persistent raster impurity error caused by either placing speakers too near the TV or changing the orientation of the TV after auto-degauss had taken place and one of the most deviant offenders, switching on a high power device right next to the TV e.g. a vacuum cleaner!
Wow, that's a big difference between the original picture and the adjusted one. It's just a shame about the purity problem. Guessing you don't have degaussing wand. One suggestion I found when I was looking for tips on getting the tube in my LC575 degaussed was to wave a transformer-based plug pack over the screen. I haven't actually tried it though, since I've had too many other projects on the workbench (and pretty much everywhere else in the apartment!) to pull it out of storage. Although it's been well over a year since I put it away, so I should probably do something about all those projects! Damn ADHD! _Shakes easily distracted fist_
Aside - after many horrifying examples of Duraleak damage, I found the best way to clean it up - white vinegar! It totally neutralizes that crap and it just falls away.
I had a Monitor with a Trinitron Tube myself, best CRT Monitor I ever had. Being a bit mischievous, I used to hint others with Trinitrons on the usually barely noticeable "Trinitron lines". :-) Ususally, when I met one of those fellows later, they said "You §#%&!! Now you said that, I see the lines all the time!!"
Make a manual degauss coil. Pretty easy to make, and use is fairly easy too. Give it a try. You have to follow a path, but there are videos about here in youtube, just search "manual degauss coil"
My grandparents had this exact model and it was immaculate, until I was teething and decided that wood grain looked like it would solve all of my problems...
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