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etpm@whidbey.com: Jul 18 09:55AM -0700 >Where could I ask for info on a misbehaving sewing machine? The sewing newsgroups are near dead and lacking this sort of info, and it's not an electronic problem   >cheers >NT Years and years ago I used to maintain industrial sewing machines. By far lubrication problems were the major cause of machine malfunctions. Dried up lube, the wrong lube, lube that had started to polymerize, contaminated lube, etc. Lube problems can cause adjustments to move because of increased friction. After lube problems was debris. Dust from thread and the fabrics being sewn gets everywhere and clogs stuff up. So give the machines a good cleaning and lubing first and then see if more work needs to be done. Eric

John Robertson <spam@flippers.com>: Jul 18 10:28AM -0700 On 2017/07/18 9:35 AM, Jeff Liebermann wrote: > always helpful.   > I'll spare you the rest of the lecture. > I'm out of time. Good luck.   Hi Jeff,   Hate to ask (I can see an oil thread looming (sorry)) but what do you recommend for oil? I figure a non-detergent 20w oil is good for most small mechanical machines lube points, and have tried synthetic oils on tiny motors (CD spin motors) with good success. I have to assume there is no ideal oil though.   Have you a preferred link for an online page that gives a good description of oils and what jobs they are best for?   WD-40 is, of course, of little use when something is seized and there are far better and cheaper solutions than WD for that problem. The best appearing to be old style ATF fluid and acetone.   http://www.instructables.com/id/Home-made-penetrating-oil/   http://www.greentractortalk.com/forums/off-topic/5498-using-50-50-mixture-atf-acetone-stuck-engines-has-worked-some.html     Thanks, John :-#)#   -- (Please post followups or tech inquiries to the USENET newsgroup) John's Jukes Ltd. MOVED to #7 - 3979 Marine Way, Burnaby, BC, Canada V5J 5E3 (604)872-5757 (Pinballs, Jukes, Video Games) www.flippers.com "Old pinballers never die, they just flip out."

tabbypurr@gmail.com: Jul 18 10:38AM -0700 > up. So give the machines a good cleaning and lubing first and then see > if more work needs to be done. > Eric   Thanks - I'm convinced that's the entire problem with the 530-2. It probably hasn't been lubed in decades. What do you reckon I should use to remove hardened oil from within parts? The only chemicals I'm thinking that could attack this effectively are ammonia & bleach, but am hesitant to use those without knowing if it's ok to.     NT

"pfjw@aol.com" <pfjw@aol.com>: Jul 18 10:53AM -0700 GRUMP!!!!   OK, this is 2017. What this means is that there are lubricants and solvents out there that are beyond the wildest dreams of those machine designers.   First, invest in some KROIL - this to saturate everything in preparation for a massive cleaning. Kroil will loosen skunge and penetrate bearings so that you do not gall anything by moving it by force. Kroil is meant as a penetrating oil, NOT as a lubricant, restorative nor anything else than what it is designed to do.   Then, when clean and re-assembled:   http://cdn3.bigcommerce.com/s-evpnwp29/products/95/images/329/SuperLube_Oil__21128.1439340805.500.500.jpg?c=2   Where oil is required. Cams & cam-followers and such.   http://www.backflowpreventer.com/media/ecom/prodlg/SuperLube.jpg   Where grease is required - gears, open shaft bearings (on the shaft and in the bearing prior to reassembly) and such.   Ancient oil & grease formula polymerized with heat and pressure. Modern synthetics will not. That puts you way ahead of the game moving forward. And the specific materials cited have a very high film strength and do not attract dust as much as non-synthetics.   Sewing needles have a 'sense', Typically the haft is D shaped. Make sure that the flat side is in the correct orientation, or you will break/bend it every time.   Remember, you are undoing years and years of neglect. If you work on the theory that I use - every machine needs a certain amount of maintenance over its life. And the real time required increases in geometric but inversely related to the timeliness of that maintenance. So, you have a number of hours ahead of you before everything will be 'right'.   I expect that the persnickety level of maintenance required is why new machines get sold despite the vast number of vintage ones out there.   Peter Wieck Melrose Park, PA

Jeff Liebermann <jeffl@cruzio.com>: Jul 18 09:35AM -0700 >fairly straightforward. I've set the bobbin & top tensions. I >suspect the top tension release mechanism is stuck. I'll take >another look but didn't say any ready access to that area of internals.   The Bernina 121 similar to the 125, which adds zig-zag but is the same as far as thread tensioning. It was also sold as a Husqvarna Zig-Zag. This should be useful: <https://www.occaphot-ch.com/bernina-oldie-modelle/bernina-modelle-kl-125-121-1950er/>   I don't know exactly what's wrong, but you have the right idea. Take it apart, clean everything, reassemble, lubricate, and adjust the tension. I don't see how you can successfully adjust the top thread tension, and then claim that it doesn't grip the thread at all. If you've removed washers, you probably took it apart and cleaned it, so I'll assume the center shaft was clean. I normally do not oil the tension disks, so if they've been oiled, that might be the problem.   If the machine has been infrequently used, is dirty or dusty, or was lubricated with 3-in-1 oil, you might consider cleaning with solvent and some new oil.   Incidentally, that may not be a "valuable" machine, but it might be quite useful. Such all-metal machines are prized for sewing leather and heavy canvas.   >Another lever also wouldn't move but a bit of persistence & >persuasion got it to. I suspect all round oiling may be the solution, >will know later.   The stuck stitch selector knob is an important clue that the machine needs cleaning and lubrication. Take the belt off and try to turn it by hand, but don't force it. If it's stiff, then you get to clean out the gum with some solvent and lubricate from scratch. If it moves freely, look at the motor. If you see blobs of oily lint, sticky goo, or rust on the shafts around the moving parts, there's the problem.   Too much oil is just as bad as not enough. Same with using the wrong type of oil. You want oil that doesn't evaporate and maintains a fairly constant viscosity over temperature. <http://www.makeit-loveit.com/2012/09/how-to-cleanoil-your-sewing-machine.html> I would go easy on "oil the whole thing" and try to isolate the cause of the drag. Adding more oil to a dirty or dusty machine just creates more sticky goo.   >I've gotten tired of googling only to find idiot advice like 'have >you put the thread in the right end,' 'don't forget to set the >bobbin tension' and 'ooh you need to take it to a dealer' type stuff.   If you specific advice for your specific problem, it's really helpful if you would supply specifics. A photo of the guts is very useful as many problems can be visually seen. Some history of the machine is always helpful.   I'll spare you the rest of the lecture. I'm out of time. Good luck.   -- Jeff Liebermann jeffl@cruzio.com 150 Felker St #D http://www.LearnByDestroying.com Santa Cruz CA 95060 http://802.11junk.com Skype: JeffLiebermann AE6KS 831-336-2558

Jeff Liebermann <jeffl@cruzio.com>: Jul 18 01:29PM -0700 On Tue, 18 Jul 2017 10:28:21 -0700, John Robertson <spam@flippers.com> wrote:   >Hi Jeff,   Not high enough.   >small mechanical machines lube points, and have tried synthetic oils on >tiny motors (CD spin motors) with good success. I have to assume there >is no ideal oil though.   First, a little background and drivel. My father owned a women's wear (mostly lingerie) factory in Smog Angeles. I got plenty of experience building, fixing, and adjusting industrial sewing machines and making attachments. Then, I discovered electronics and largely abandoned sewing machinery. Lately, I've become rather bored with electronics, computing, and some of my other activities, and though it might be interesting to do sewing machine repairs on the side. Big mistake, but I won't bore you with the problems I created. Meanwhile, I've collected a small collection of older machines, most of which are being slowly repaired and sold. Not the best credentials but perhaps good enough for the basics.   Oil for sewing machines, microscopes, guns, and clocks all have two requirements that must be met. The oil should not evaporate and should remain at a constant viscosity over the working temperature range. That's because these devices rely on residual friction of the lubricant to control the movement of mating parts. Changes in this friction will result in undesirable changes in timing and adjustment.   Big industrial sewing machines solve the gum and evaporation problems by using an oil sump and splash lubrication. It won't turn to gum because additional oil just washes away the gum. It can evaporate, but with so much oil in the sump, it's unlikely to ever be run without oil. Too bad it makes such a big mess. I've also never seen an oil sump on a home type sewing machine.   Another way is to do it like an automobile engine, and pump oil down an oil gallery into mating surfaces via holes in the bushings. That works, but is too complicated, expensive, and messy for a home machine.   So, what's left? Felt oil pads is what most home machine use. That works, but requires much better oil than the previous 2 methods of lubrication. That is why you don't use engine oil, WD40, penetrating oil, or home brew in a sewing machine. None of these oils are constant viscosity or even close to the viscosity specified by the sewing machine design. Even clock oil is marginal, because clocks are not designed to handle the rotational speeds and reciprocating pounding found in sewing machines.   So, what works? Ummm... sewing machine oil perhaps? They're largely all the same stuff different in viscosity for different manufacturers. <https://www.mobil.com/en/industrial/lubricants/product-series/mobil-velocite-sm-series> Ok, so you're not going to buy it by the gallon, but the specs are the same as what you get with retail overpriced sewing machine oil.   >Have you a preferred link for an online page that gives a good >description of oils and what jobs they are best for?   No, but I'll see if I can find something. I doubt if anyone can get all the various types of lubricants on a single web page. In general, the lube selection pages of the major oil companies do better than the specialty oil formulation pages. For example start here: <https://www.mobil.com/en/industrial> I'll see if I can find some more links later.   >appearing to be old style ATF fluid and acetone. >http://www.instructables.com/id/Home-made-penetrating-oil/ >http://www.greentractortalk.com/forums/off-topic/5498-using-50-50-mixture-atf-acetone-stuck-engines-has-worked-some.html   We had this discussion in some newsgroup recently. The consensus among those that tried acetone and ATF as a penetrating oil varied radically from it works great, to it sucks. Several people discovered that there are different types of ATF, one of which wouldn't even mix properly with acetone. I'll see if I can find the thread.   Please note that penetrating oil is not a lubricant.   -- Jeff Liebermann jeffl@cruzio.com 150 Felker St #D http://www.LearnByDestroying.com Santa Cruz CA 95060 http://802.11junk.com Skype: JeffLiebermann AE6KS 831-336-2558

tabbypurr@gmail.com: Jul 18 02:48PM -0700 On Tuesday, 18 July 2017 17:35:26 UTC+1, Jeff Liebermann wrote: > >another look but didn't say any ready access to that area of internals.   > The Bernina 121 similar to the 125, which adds zig-zag but is the same > as far as thread tensioning. It was also sold as a Husqvarna Zig-Zag.   The 125 is worth something, the 121 I doubt it. I don't plan to keep it, I've got far more capable machines. If I can get it going without hassle it'll bring in double what I paid for the pair & be useful to someone. It's the 530-2 I'm willing to spend more time on.   > This should be useful: > <https://www.occaphot-ch.com/bernina-oldie-modelle/bernina-modelle-kl-125-121-1950er/>   interesting, but that's all   > you've removed washers, you probably took it apart and cleaned it, so > I'll assume the center shaft was clean. I normally do not oil the > tension disks, so if they've been oiled, that might be the problem.   the lack of thread tension puzzled me. It works just fine with one washer removed, so it's a low priority issue.   > If the machine has been infrequently used, is dirty or dusty, or was > lubricated with 3-in-1 oil, you might consider cleaning with solvent > and some new oil.   Yes... question is which solvent. White spirit? Paraffin/kerosene? I've got those. Also have ammonia & bleach if they'd attack the crud without causing damage.   > Incidentally, that may not be a "valuable" machine, but it might be > quite useful. Such all-metal machines are prized for sewing leather > and heavy canvas.   Ten a penny I think.   > always helpful.   > I'll spare you the rest of the lecture. > I'm out of time. Good luck.   I've not psoted pics because I don't believe they'd be in any way helpful. The mechanism is quite dense. Looking at the thing IRL it's hard enough to see what's going on with moving one's vision at all sorts of angles, I can't see a photo being comprehensible. I'll see what I can get tomorrow but I doubt it'll give much away.   History is unknown, I got them at a clearance for peanuts. The lubrication disaster tells me they've either not been used in a long time, or had no care taken of them at all.     NT

tabbypurr@gmail.com: Jul 18 03:03PM -0700 > I expect that the persnickety level of maintenance required is why new machines get sold despite the vast number of vintage ones out there.   > Peter Wieck > Melrose Park, PA     I see you like to spend :) I use baby oil on sewing machines, it's a light petroleum derived clear oil with a trace of perfume. Whether babies were harmed in it's making remains to be seen.   These machines don't have any felt pads, oil just hangs around in the moving parts by surface tension. They're certainly not high speed mechanisms, they're overengineered to be just about bombproof.   The 530-2 runs stiffly but it runs & sews now. But frequently the mechanism stiffens a good bit & motor speed drops right down. Hopefully paraffin will help. There are also still key parts that remain stuck. 15 minutes in the oven at 50C freed up 3 controls, but 2 remain well stuck so far. Paraffin is next.     NT

Jeff Liebermann <jeffl@cruzio.com>: Jul 18 11:21PM -0700 >> This should be useful: >> <https://www.occaphot-ch.com/bernina-oldie-modelle/bernina-modelle-kl-125-121-1950er/>   >interesting, but that's all   You're hard to please.   >the lack of thread tension puzzled me. It works just fine with >one washer removed, so it's a low priority issue.   It may have been disassembled and then put back together incorrectly. >Yes... question is which solvent. White spirit? Paraffin/kerosene? >I've got those. Also have ammonia & bleach if they'd attack the >crud without causing damage.   Oh, that's easy. Anything that will dissolve the original sewing machine oil. Even if it's dried out or turned to goo, it's still the same oil, which can be dissolved by anything from paint thinner to kerosene. I wouldn't go any higher up the chlorinated hydrocarbon tree because those tend to dull or eat plastic parts. I tend to favor kerosene (lamp oil) for loosening up machine parts. If I'm lazy, I just dump some more sewing machine oil on the part, which will dissolve the gum, but not the stuff that has hardened. As little scraping with a piece of wood or plastic (not metal) will expedite things.   What's the story behind using ammonia and bleach? I've never heard of that concoction.   The reason I want a photo is because I've seen a few Frankenstein monsters assembled from parts from different machines. I've also spent an inordinate amount of time digging out information on what turned out to be the wrong model number. Trust, but verify.   >History is unknown, I got them at a clearance for peanuts. The >lubrication disaster tells me they've either not been used in a >long time, or had no care taken of them at all.   Thanks for the details. Some of mine were left outside in the rain. Rust everywhere. I think you have the right approach. Clean, lube, adjust, and try again.       -- Jeff Liebermann jeffl@cruzio.com 150 Felker St #D http://www.LearnByDestroying.com Santa Cruz CA 95060 http://802.11junk.com Skype: JeffLiebermann AE6KS 831-336-2558

tabbypurr@gmail.com: Jul 19 05:18AM -0700 On Wednesday, 19 July 2017 07:21:53 UTC+1, Jeff Liebermann wrote: > >> <https://www.occaphot-ch.com/bernina-oldie-modelle/bernina-modelle-kl-125-121-1950er/>   > >interesting, but that's all   > You're hard to please.   :) If there's anything online about actual repairs to Berninas I've not found it.   > >the lack of thread tension puzzled me. It works just fine with > >one washer removed, so it's a low priority issue.   > It may have been disassembled and then put back together incorrectly.   Probably so. I'll recheck the central split threaded rod for blockage. I reckon I know how to sort it now.   > dissolve the gum, but not the stuff that has hardened. As little > scraping with a piece of wood or plastic (not metal) will expedite > things.   Kerosene it is. Scraping is mostly not viable, taking the whole mechanism apart is not on the to do list, only 2 bits have scrape access.     > What's the story behind using ammonia and bleach? I've never heard of > that concoction.   Either can tackle congealed oil. Ammonia is the more effective & antisocial. Don't mix them.     > Thanks for the details. Some of mine were left outside in the rain. > Rust everywhere. I think you have the right approach. Clean, lube, > adjust, and try again.   Yup. Will get some pics. Cheers.     NT

Charlie+ <charlie@xxx.net>: Jul 19 09:05AM +0100 On Tue, 18 Jul 2017 14:48:05 -0700 (PDT), tabbypurr@gmail.com wrote as underneath :   snip   >Yes... question is which solvent. White spirit? Paraffin/kerosene? I've got those. Also have ammonia & bleach if they'd attack the crud without causing damage.   I would try naptha (lighter fluid) first as that will be compatible with the petroleum oils originally used. C+

Cursitor Doom <curd@notformail.com>: Jul 18 09:22PM On Mon, 17 Jul 2017 16:50:18 -0700, tabbypurr wrote:   > do they have some form of regulation? I've used very basic cranked > meggers, not those old ones, and the readings were wobbly.   > NT   They specify how many RPM you should turn the handle at in the instructions. Presumably they then have a motor to drive the thing at that speed in the factory for calibration purposes. In practice, the output gets progressively less 'wobbly' the faster you go and they're intended to be spun-up pretty fast. Fuck knows how they expect you to judge the specified RPM when taking measurements, though!

tabbypurr@gmail.com: Jul 18 03:05PM -0700 On Tuesday, 18 July 2017 22:26:19 UTC+1, Cursitor Doom wrote: > In practice, the output gets progressively less 'wobbly' the faster you > go and they're intended to be spun-up pretty fast. Fuck knows how they > expect you to judge the specified RPM when taking measurements, though!   Even at constant speed it's going at differing speeds at different parts of the turning cycle. The ones I used had very low handle speed and were far from steady. But they picked up bad insulation ok.     NT

Cursitor Doom <curd@notformail.com>: Jul 18 11:41PM On Tue, 18 Jul 2017 15:05:38 -0700, tabbypurr wrote:   > Even at constant speed it's going at differing speeds at different parts > of the turning cycle. The ones I used had very low handle speed and were > far from steady. But they picked up bad insulation ok.   Yup, and as Ralph has already said, they're really not designed for precision accuracy. They tell you only what you really *need* to know and no more and since they are like 60yr old technology, it's not fair to compare them to the currently available stuff anyway.

Jeff Liebermann <jeffl@cruzio.com>: Jul 19 12:02AM -0700 >parts of the turning cycle. The ones I used had very low handle speed >and were far from steady. But they picked up bad insulation ok. >NT   Same here. Mine gives a reading, but varies somewhat with the crank speed: <http://www.11junk.com/jeffl/pics/Megger/slides/Megger-Major.html> There's also a leather case and a tangle of wire leads. I just took it for a spin with a handy 22M resistor. Something is wrong as I'm getting very unstable readings. That's not surprising since the insides are filthy. I've been afraid to clean it lest the insulation crumbles.   There are some videos on YouTube mostly showing how to use a Megger. <https://www.youtube.com/results?search_query=megger>   The technology is quite old and rather crude by todays standards, but still useful for what it was originally intended (measuring high resistances).   -- Jeff Liebermann jeffl@cruzio.com 150 Felker St #D http://www.LearnByDestroying.com Santa Cruz CA 95060 http://802.11junk.com Skype: JeffLiebermann AE6KS 831-336-2558

Jeff Liebermann <jeffl@cruzio.com>: Jul 19 12:12AM -0700 On Wed, 19 Jul 2017 00:02:50 -0700, Jeff Liebermann <jeffl@cruzio.com> wrote: (...)   "What not to do with a Megger" <https://www.youtube.com/watch?v=riYEUWa8trc>     -- Jeff Liebermann jeffl@cruzio.com 150 Felker St #D http://www.LearnByDestroying.com Santa Cruz CA 95060 http://802.11junk.com Skype: JeffLiebermann AE6KS 831-336-2558

oldschool@tubes.com: Jul 18 02:13PM -0400 On Mon, 17 Jul 2017 17:01:00 -0700, "David Farber" >-- >David Farber >Los Osos, CA   If it lasted several years, you probably got your moneys worth out of it. If I recall correctly, from the commercials, they sold for about $20 (plus S&H). I'd probably just buy another one, if your cat loves it. Sounds like your cat is worth it. However I do understand you wanting to try to fix it. But you're up against a item made to be disposible, with no ID on the transistors. And even if you do get it to work, how long will those motor brushes last?   But hey, we all tackle projects like this. Sometimes we win, often we lose. If you do get it to work, maybe you will be the first to find suitable replacment parts.... And your efforts will help someone else with the same toy.   I wonder what these cat toys sell for on Ebay?   Yea, I know all about cats bringing dead (or sometimes live) mice into the house. They are offering you a gift, even though I know I sure dont want it..... But I do like cats.

"pfjw@aol.com" <pfjw@aol.com>: Jul 18 01:09PM -0700 On Monday, July 17, 2017 at 8:01:38 PM UTC-4, David Farber wrote:   > their catches to us. As a result, we've had to decommission the kitty door > to the outside world. Now they can only go out when we let them and then > will only be let back in if they are not bringing anything with them.   Bad move!   Your cats think that you are a particularly incompetent hunter, eat all kinds of weird, smelly, dead food and generally are not very good cats. So, they are trying to feed you, and train you as they would their kittens. The proper response is to *immediately* praise the cat, and then pick up the gift and remove it to some location that the cat will never find in the future - make it 'gone'. Do not flush it in the presences of the cat, or dispose of it in some similar way in sight of the cat. That is, to the cat, a completely incomprehensible reaction to a sincere gesture.   Just be glad the cats are not focused on bringing you live prey for specific training. We had a big Maine Coon that decided he was going to 'train up' our Scottie when she was a puppy - he was a LOT bigger than she was at the time. Several full-sized live squirrels and one yearling raccoon later, we had to explain to him the difference between cats and dogs. Sadly we lost him to cancer (at 16) shortly there after.   Peter Wieck Melrose Park, PA

"David Farber" <farberbear.unspam@aol.com>: Jul 18 02:53PM -0700 Dave Platt wrote: > current capacity.   > ZTXN2038F is one of many examples... 1A continuous collector current, > 2A peak pulse current. Digi-Key wants $0.41 in onesies.   Hi Dave,   That should work great! However there was no pinout in the datasheet. https://www.diodes.com/assets/Datasheets/ZXTN2038F.pdf   I e-mailed diodes.com tech support to see if they can supply that information.   Thanks for your reply. -- David Farber Los Osos, CA

tabbypurr@gmail.com: Jul 18 03:09PM -0700 > Yea, I know all about cats bringing dead (or sometimes live) mice into > the house. They are offering you a gift, even though I know I sure dont > want it..... But I do like cats.   It's an easy enough repair. But need to be clear on the motor current, a motor that runs at 0.3A will kill 0.3A transistors. The question is what is the stalled motor current. Once the requirements are clear any junkbox should contain something suitable.     NT

tabbypurr@gmail.com: Jul 18 03:10PM -0700 > Just be glad the cats are not focused on bringing you live prey for specific training. We had a big Maine Coon that decided he was going to 'train up' our Scottie when she was a puppy - he was a LOT bigger than she was at the time. Several full-sized live squirrels and one yearling raccoon later, we had to explain to him the difference between cats and dogs. Sadly we lost him to cancer (at 16) shortly there after.   > Peter Wieck > Melrose Park, PA   The odds of putting a caught mouse somewhere the cat will never know are very small. Put it in the cat's food bowl a little later & they take it as a gift and enjoy.     NT

dplatt@coop.radagast.org (Dave Platt): Jul 18 04:09PM -0700 >https://www.diodes.com/assets/Datasheets/ZXTN2038F.pdf   >I e-mailed diodes.com tech support to see if they can supply that >information.   Take a look at   http://www.electro-tech-online.com/attachments/pinouts-png.30877/   as it has a whole bunch of pinouts. From what I read, it appears that the SOT-23-3 package for transistors has highly standardized pinouts.

"David Farber" <farberbear.unspam@aol.com>: Jul 18 05:55PM -0700 Dave Platt wrote:   > http://www.electro-tech-online.com/attachments/pinouts-png.30877/   > as it has a whole bunch of pinouts. From what I read, it appears that > the SOT-23-3 package for transistors has highly standardized pinouts.   Yes, that matches what the old part is. I'm in no hurry so I'll wait to see what diodes.com has to say.   Thanks for your reply. -- David Farber Los Osos, CA

"Ian Field" <gangprobing.alien1@virginmedia.com>: Jul 18 06:37PM +0100 <jurb6006@gmail.com> wrote in message news:c90a37ab-d11a-4c41-84d3-6edb39f6a0f9@googlegroups.com...   >> If its that bad - you probably need to sort out the purity first.   >> I didn't think RCA PIL tubes still had those.   > What is a PIL tube ?   May have been a copyright dodge to avoid the Trinitron.   It was an early example of inline guns to avoid the hard work of purity and convergence with delta gun layouts.   The phosphors were probably stripes like the Trinitron, but I think the shadowmask had an array of staggered slots - the Trinitron shadowmask is more like a Venetian blind.   I vaguely remember the RCA PIL tubes having bonded yokes, there may have been purity rings on the tube neck, but purity was largely factory set.   Adjustment was much simpler with PIL tubes, and mostly done by careful magnetics design.   A degaussing wand might help - but keep it away from the tube neck.

John-Del <ohger1s@gmail.com>: Jul 18 01:42PM -0700 On Tuesday, July 18, 2017 at 1:37:35 PM UTC-4, Ian Field wrote:   > >> I didn't think RCA PIL tubes still had those.   > > What is a PIL tube ?   > May have been a copyright dodge to avoid the Trinitron.   Perhaps, but I think most of Sony's engineering efforts were to avoid everyone else's patents. Their 70s power supply designs are a Rube Goldberg's nightmare wrapped in a chain saw wielding mass murderer's warm embrace. They weren't notably efficient or particularly well regulating, so my guess is that they were building a unique design with no patents (and really, who would patent such an abortion?).   I remember when NYC was reducing power during the 70s in an "energy saving" attempt. Well Sony power supplies committed harakiri at not much less than 100VAC, and lots of Trinitrons were blowing up during the brown-outs.   As far as in-line tubes, I remember seeing mid 60s GE Portacolor TVs use in-lines although I believe they were of delta configuration. Decent tube, easy to converge and outlasted the TV but the TV itself was a toilet. Terrible picture that would feature not only changing black level and AGC action but even change in color temperature as the brightness was advanced, and this was at the demodulators, not the CRT.   The Trinitron when it worked right produced some fabulous images, but I think the tube was very finicky and required far more stringent manufacturing tolerances than the typical tube, hence the cost. Give it a small nudge and the shadow mask would shift or one of the wires would snap. Early tubes had the coaxial second anode connector and those tubes would short internally.   Don't miss those days. (much)

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