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.
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.
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!
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
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.
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.
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!
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.
@@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.
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...
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
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.
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.
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.
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.
What I don't get is that I've the European version, which has no digital tuning but 12 tuning wheels, does have a way more modern remote. It is the same champagne silver, but with rectangular buttons, and way more buttons, more like the later black Sony remotes. You can alter brightness, saturation and contrast on it, while controls for it are also available under the lid as physical wheels for example.
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.
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.
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.
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.
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.
"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!!!
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.
do you have a degaussing wand? i'd try that next I have a Sony PVM (much newer than this), but it's always had a slight purity issue and it seems to stem from the internal speaker's magnet. I'm not sure if there was some kinda shielding that wore out or got dislodged. I can often place a magnet on the TV in just the right spot to make it go away.
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.
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!
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'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.
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 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.
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.
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.
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.
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)."
There could be a few purity magnets hidden by the CRT shield, most were affixed to the CRT by double sided foam tape. Could be the magnet(s) is delaminating from the foam tape and flopping about just enough to change position when you rotate the tv?
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.
I've recently scored a "last generation" trinitron TV on e-bay (waiting for the package now) and read up on the service manual. It mentions that the color purity in the corners is controlled by four permanent magnets stuck to the back of the CRT... maybe this model has something similar and one came off or shifted? Other than that, a bit of manual degaussing (like other comments) seems a good idea;
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.
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.
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.
Magnetic fields in the environment can be part of it (on an older video, I think from a few years ago, he took one apart and compared it to another one which was unaffected) Edit: specifically the degaussing coil was too small in that TV and the fix ended up being putting a different TV’s coil inside. Because as mentioned and shown in this video, power cycling it while in an orientation with more impurity didn’t properly fix it in that one either.
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.
Also known as the contrast control, it controls how bright the picture is without washing out the picture. The control named brightness adjusts the black level. Set that one high and everything is washed out, set it low and you lose all the details in the shadows. In my opinion it would make more sense if the brightness and contrast labels were reversed. Or mathematically speaking, y=ax+b. Y is the brightness of the beam, A is the contrast control, X is the incoming signal, and B is the brightness control.
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.
Adrian @Adrian's Digital Basement ][ .... 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 ...
The speaker is on the top of this set and is a shielded type. I don't really see how that metal shield or implosion band can become magnetized in one super specific spot -- and in such a way the built in degaussing coil has no effect on it.
@@adriansdigitalbasement2 maybe it was in storage near a big speaker and the metal chassis.. or the bracket that holds the tube or the screw in the bracket .. or that shield around the tube pick up magnetism in that corner... just like a screwdriver takes magnetism by rubbing over a magnet ... One of the adjustment magnets of the tube fell off and is stuck down there (that was my first thought).. But I guess you would have seen it stick down there... You have violet (north pole of a magnet) in the corner of the tube... where the metal shield bends... and green (south pole of a magnet) is at a specified distance ... you said it clearly there is something magnetic down there... in that corner.. or something inducing magnetism in that corner... is a huge wire (ceramic) resistor screwed there in tht shield.. (under the speaker) .... if it is dissipating more power than it should .. can create a magnetic field in all that can around the tube.. Start to remove things from that corner and see if it changes ... the degauss coil can degauss the tube .. but it will not degauce something magnetic or inducing magnetism near the tube
I don't know if it was released in the US, but here in the UK the Sony Trinitron KV-1400U was used in a lot of 80's computer adverts (you can see it on the box of the Dragon 32 and also in the ZX Spectrum brochure) A very nice TV and quite sought after. Just wish I knew how to add a composite video input!
Looks like the image is tilted slightly. Could be camera artifact though. If it is though you'd have to rotate the yoke to fix that. Could also be why you have that purity issue. Though most likely that purity issue just needs a stronger degausser. What'd you probably need is one of those deguassing wands which should take care of that once and for all. I have a similar TV. A KV-1393R. 13 incher made in September '88. Much more integrated then that one too. Only one PCB in the whole thing and has a basic OSD instead of LED channel indicators. Got it for $10 off Facebook Marketplace a couple years ago. I ended up swapping the tube in it with one from a KV13TR24 that I got off ebay recently before that. The tubes for that one were interchangable. (even the yokes could be used on either one). The original one in the 1393R has no convergance adjustment rings on it what so ever and the red convergance was out of wack. Despite trying to move the yoke around to fix it, I couldn't really get it any better. So I just swapped out the tubes (I tried swapping the yokes first but the other yoke couldn't quite bring it in where I wanted). Was able to get the convergance down pretty good despite swapping the yokes out entirely and what not. The tube in it now that came from the KV13TR24 didn't have perfect convergence either and right now it's better then where it was originally. Anyways I love my KV-1393R and the whole reason I swapped the tubes to make it my main set was because the 93R also had woodgrain design for the sides. Unlike your model though mine had proper woodgrain pattern on it. There's appearently a non woodgrain version of my set that is more common so it was rare that I found a woodgrain version. Woodgrain was starting to go out of style after 1988/1989 when the 90's were around the corner so Sony probably stopped making woodgrain designs soon after the model of TV I got and was already making some non woodgrain versions that where more common.
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.
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's Digital Basement ][](http://yt3.ggpht.com/ytc/AIdro_k7CrQRe71qN6c0Ua7A1P_I8KkxjqLa70u0zYeCvdvnKw=s48-c-k-c0x00ffffff-no-rj)
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.
It's becoming more and more like a CRT restoration channel, I like it !
couldn’t agree more!
Adrian's Analog Basement....
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.
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.
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!
Yeah I have a mirror handy which I'd normally use if I wasn't recording. Two cameras and all that is too much for the second channel hehehe.
Haha. Makes sense!
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
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 👍
My dad did TV repair for a living and I remember him using a degaussing wand to fix issues like this, worked a treat.
Also love the channel!
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.
We used those small Sony TV's as monitors all over the TV stations where I was working back then.
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.
O man this is the tv i had in my room as a kid forever. Still looks nice, glad i got saddled with the old stuff.
This reminds me of fiddling for hours on voltage pots on a magnet sector mass spec. It's crazy how fine tuned you can make these analogue devices.
It's also crazy how much time it took to perform a proper convergence. Fred
@@electronicengineer lol yeah especially when the guy who used the instrument last installed the lenses wrong.
The “Wood grain” is simulated burly wood pattern or perhaps leather grain.
Yep, I have the same pattern on the dash of my car! Lol!
LGR would approve! :)
Burl is what I was going to say, you must also be a woodworker lmaoo
@@DerekWitt I'm not that sure, in fact, if you pay attention, in this thread the woodgraininess of the thing is at stake.
yes, burl is the word i was looking for.
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!
I always loved Sony Trinitron TVs, I really like the colors and image quality on a good Trinitron CRT
i like how back then they all wanted to sound futuristic, i had an old zenith where the remote control has "space command" written on it
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 thing is beautiful. Also, does anyone remember remotes with wires going to the tv? I’m only 42, but my parents kept stuff for years
My parents had a silver VCR that had a wired remote in the early 80s. I don't remember the brand. It was a top loader.
Jup. And remotes that used ultrasound to transmit in stead of IR.
@@misterkite, quazar maybe? We had something that was a quazar brand that was silver with woodgrain
@@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.
I remember the wires (OSHA where were you) they were a tripping hazard, till they broke, then I was the remote control again.
That CRT has your intitals in the model number!
Definitely match made in 1984 :-)
Great review bro.
I do have a 20 years old Samsung Hitron CRT tube 📺 . Still it giving great picture.... 💗
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...
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
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.
I don't know why, but this made me want to watch an episode or two of Columbo!
Columbo rocks!!
OMG thank you Adrian - Iwas desperately searching for something to watch! ❤❤
Another fun video for the second channel, thank you sir!
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.
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.
I picked up this same model Trinitron last year, excellent picture quality for an RF-only set and I love its looks.
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.
What I don't get is that I've the European version, which has no digital tuning but 12 tuning wheels, does have a way more modern remote. It is the same champagne silver, but with rectangular buttons, and way more buttons, more like the later black Sony remotes. You can alter brightness, saturation and contrast on it, while controls for it are also available under the lid as physical wheels for example.
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.
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! :(
You're so lucky get another Sony TV, very nice.
Loving the CRT goodness. Keep them coming!
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.
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.
Very cool!
I’d love to know more about your test pattern generator.
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.
Please, make more Trinitron videos.
Love your chanels.
Oh, and thats a nice Trinitron.
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.
"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!!!
The "Wabbit ears" would connect via a coax cable to the VHF "F" connector, while a UHF loop antenna would screw onto the two binding posts.
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.
do you have a degaussing wand? i'd try that next
I have a Sony PVM (much newer than this), but it's always had a slight purity issue and it seems to stem from the internal speaker's magnet. I'm not sure if there was some kinda shielding that wore out or got dislodged. I can often place a magnet on the TV in just the right spot to make it go away.
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.
Loving this mini series about old Sony Trinitrons :D
I had a new 1985 27" Trinitron I won in a contest, best thing I ever won! The remote control was very similar.
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!
Heh! Without a doubt, back in the 70s and 80s, no one could even come close to matching Sony picture quality. They were at the top of their game.
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'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.
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 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.
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.
I was born in 1975 too!!! The best year, the best of them all, oooooobviously!
And my first computer also was a Vic-20, my dad borrowed it from someone, we had to return it after a while but then he bought us a C128 :-D
That back removal would have looked amazing in 3D!
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.
i had a 25 inch or so i found in a dump about 15 years ago brand new still in box took it plugged it in and worked great i used that tv for 6 years
them trinitrons was nice
Then what happened to it?
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.
This one perhaps?
www.hifi-archiv.info/Philips/Philips-1984-Video/36.jpg
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)."
lgr would approve of the wood grain on this tv
The picture looks like it's at an angle? That would involve adjusting the yokes? Maybe that would help with the corner?
There could be a few purity magnets hidden by the CRT shield, most were affixed to the CRT by double sided foam tape. Could be the magnet(s) is delaminating from the foam tape and flopping about just enough to change position when you rotate the tv?
@Adrian's Digital Basement ][ Maybe the ring around the CRT is needing to be adjusted like on computer monitor
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.
I've seen those color blotches on TVs before. You will never get rid of that. I've seen them last for a LONG time. lol
I've recently scored a "last generation" trinitron TV on e-bay (waiting for the package now) and read up on the service manual. It mentions that the color purity in the corners is controlled by four permanent magnets stuck to the back of the CRT... maybe this model has something similar and one came off or shifted? Other than that, a bit of manual degaussing (like other comments) seems a good idea;
I was thinking I already watched this video. Boy, was I in for a surprise!
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.
Maybe try an external degaussing coil?
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.
Try to move some ordinary magnets in front of the tube and move it away and down FASTER - the smuges will disapier after some repeats :)
And with wood grain that LGR would approve. :)
Have you tried tweaking the purity rings?
Regarding the remote, have you considered making a new pcb for the remote? I would be up for taking a stab at that if you would like.
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.
What causes the purity issues to change location when the monitor is tilted?
Magnetic fields in the environment can be part of it (on an older video, I think from a few years ago, he took one apart and compared it to another one which was unaffected)
Edit: specifically the degaussing coil was too small in that TV and the fix ended up being putting a different TV’s coil inside. Because as mentioned and shown in this video, power cycling it while in an orientation with more impurity didn’t properly fix it in that one either.
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.
What did the "Picture" knob/adjustment exactly do on CRTs? I always remembered I preferred to turn mine DOWN.
Also known as the contrast control, it controls how bright the picture is without washing out the picture. The control named brightness adjusts the black level. Set that one high and everything is washed out, set it low and you lose all the details in the shadows. In my opinion it would make more sense if the brightness and contrast labels were reversed.
Or mathematically speaking, y=ax+b. Y is the brightness of the beam, A is the contrast control, X is the incoming signal, and B is the brightness control.
But I also remember the contrast control being a thing. Are you sure Picture=Contrast?
Could you add a magnet to the opposite side of the purity problem
Hi Adrian! Did you check the degauss PTC if it's working?
Another Trinitron episode, were spoiled! :)
The purity could be the TV was set next to speakers. an external degaussing coil might be a good investment.
As some mention, you could try a magnet, but be careful. Alternatively look for interference - maybe it's from the power cord?
I noticed that some of the pots were sketchy. Just confirming you hit all of them with DeoxIT D5 yes?
Take it from me; that's a nice Sony classic! 👌
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.
Adrian @Adrian's Digital Basement ][ .... 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 ...
The speaker is on the top of this set and is a shielded type. I don't really see how that metal shield or implosion band can become magnetized in one super specific spot -- and in such a way the built in degaussing coil has no effect on it.
@@adriansdigitalbasement2 maybe it was in storage near a big speaker and the metal chassis.. or the bracket that holds the tube or the screw in the bracket .. or that shield around the tube pick up magnetism in that corner... just like a screwdriver takes magnetism by rubbing over a magnet ...
One of the adjustment magnets of the tube fell off and is stuck down there (that was my first thought).. But I guess you would have seen it stick down there...
You have violet (north pole of a magnet) in the corner of the tube... where the metal shield bends... and green (south pole of a magnet) is at a specified distance ...
you said it clearly there is something magnetic down there... in that corner..
or something inducing magnetism in that corner...
is a huge wire (ceramic) resistor screwed there in tht shield.. (under the speaker) .... if it is dissipating more power than it should .. can create a magnetic field in all that can around the tube.. Start to remove things from that corner and see if it changes ...
the degauss coil can degauss the tube .. but it will not degauce something magnetic or inducing magnetism near the tube
the color spot maybe can be removed with a strong magnet? wave it close to the spots...it will go away..at least mine old pc monitor did ;D
I don't know if it was released in the US, but here in the UK the Sony Trinitron KV-1400U was used in a lot of 80's computer adverts (you can see it on the box of the Dragon 32 and also in the ZX Spectrum brochure) A very nice TV and quite sought after. Just wish I knew how to add a composite video input!
That was only ever a PAL TV -- so not sold here. Wouldn't it have SCART? Several people said here by the 80s all TVs had SCART in Europe.
Unfortunately not, no scart on this TV. Scart was more a late 80's connection over here.
Looks like the image is tilted slightly. Could be camera artifact though. If it is though you'd have to rotate the yoke to fix that. Could also be why you have that purity issue. Though most likely that purity issue just needs a stronger degausser. What'd you probably need is one of those deguassing wands which should take care of that once and for all.
I have a similar TV. A KV-1393R. 13 incher made in September '88. Much more integrated then that one too. Only one PCB in the whole thing and has a basic OSD instead of LED channel indicators. Got it for $10 off Facebook Marketplace a couple years ago. I ended up swapping the tube in it with one from a KV13TR24 that I got off ebay recently before that. The tubes for that one were interchangable. (even the yokes could be used on either one). The original one in the 1393R has no convergance adjustment rings on it what so ever and the red convergance was out of wack. Despite trying to move the yoke around to fix it, I couldn't really get it any better. So I just swapped out the tubes (I tried swapping the yokes first but the other yoke couldn't quite bring it in where I wanted).
Was able to get the convergance down pretty good despite swapping the yokes out entirely and what not. The tube in it now that came from the KV13TR24 didn't have perfect convergence either and right now it's better then where it was originally.
Anyways I love my KV-1393R and the whole reason I swapped the tubes to make it my main set was because the 93R also had woodgrain design for the sides. Unlike your model though mine had proper woodgrain pattern on it. There's appearently a non woodgrain version of my set that is more common so it was rare that I found a woodgrain version. Woodgrain was starting to go out of style after 1988/1989 when the 90's were around the corner so Sony probably stopped making woodgrain designs soon after the model of TV I got and was already making some non woodgrain versions that where more common.
I can just smell that Trinitron goodness....ummmmmm, niiiiice.📺😄
Can it be RGB modded? Or is there some other way to get a better signal than RF
Except for the tuner section on top, it looks almost like a burl-wood veneered Commodore 1702
You're so right! This comment deserves more love, you really nailed it.
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.
Old electronics were so damn beautiful
Try seeing if the impurities have to do with magnetic fields from underneath your workbench.
My trinitron has similar purity issues, but it clearly had been dropped before I got it. I guess strong force can also misalign the aperture grill.
It is very fragile compared to a shadow mask on a convectional CRT
Maybe you need to degauss it Shango066 style using an external degaussing coil.
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 📺