- Intermittent Fault :( - 7 Updates
- Apple throttled your iPhone by cutting its speed almost in HALF! - 3 Updates
- HISENSE 161364 POWER SUPPLY BOARD - 1 Update
| Cursitor Doom <curd@notformail.com>: Mar 02 09:33PM Gentlemen, I'd welcome any constructive suggestions on how to proceed with tracking down this elusive and annoying fault. The problem presents as a blank CRT screen on the network analyser I'm working on currently. Inititally I discovered the screen was being blanked not just during re-traces, but *permanently* - there appeared to be a rogue logic signal somewhere responsible. However, it turns out the problem goes away and the screen instantly comes back when I press and tap on various areas of the motherboard or the cards that slot into it. The trouble is, there doesn't seem to be one specific area that's susceptible to this tapping and bending. First it appears to be a bad joint/ connection on the motherboard, then it's one of the slot-in boards and then next time again, a different board - but all capable of misleadingly appearing to be the site of the poor connection. Any ideas as to how to narrow the search area right down to something manageable? Thanks. |
| abrsvc <dansabrservices@yahoo.com>: Mar 02 02:05PM -0800 My first guess is that there is a line on the bus that carries that signal and it is being interrupted. Check for any cards that are in pressure type connectors where the board provides the "jumper" between the fingers. Could be as simple as some corrosion on the fingers or the pads on the boards. Look for the simple stuff first. Something as simple as removing and re-inserting the cards a few times might be enough. It doesn't take much to mess up a signal. Dan |
| John Robertson <spam@flippers.com>: Mar 02 03:19PM -0800 On 2020/03/02 1:33 p.m., Cursitor Doom wrote: > Any ideas as to how to narrow the search area right down to something > manageable? > Thanks. Monitor the picture tube pins. You may have a problem with the HV transformer that is losing one of various supplies that the tube needs to work. Or a simple connection failure - such as is often found with circuit boards that have only a single sided PCB and Molex style pin connectors (solder cracks at the terminals)... A dual trace scope helps with this sort of troubleshooting. Leave one lead tied to the picture tube cathode so you can see the signal at the tube, and use the other lead to check the signal path while tapping. The idea is to divide in half the circuits relating to the tube, while watching the cathode to make sure it is something unrelated to the video signal that is causing the image to vanish. John :-#)# |
| Cursitor Doom <curd@notformail.com>: Mar 03 09:20AM On Mon, 2 Mar 2020 15:19:31 -0800, John Robertson <spam@flippers.com> wrote: >Monitor the picture tube pins. I'd prefer to avoid the EHT areas until every other possibility has been eliminated! I don't think that will be necessary anyway. In the absence of any better ideas, I've decided I'm going to have at it with Arctic Spray in the hope of exposing a dry joint somewhere. The appeal here is that there's no mechanical stress being applied except in the immediate area of application and I've already found that this fault is unusually sensitive to any form of physical stress. |
| Mike Coon <gravity@mjcoon.plus.com>: Mar 03 10:59AM In article <648s5f9ejs8j7qfvdk7c12t5jrtlsni2de@4ax.com>, curd@notformail.com says... > The appeal here is that there's no mechanical stress being applied > except in the immediate area of application and I've already found > that this fault is unusually sensitive to any form of physical stress. I was going to suggest spray for exactly that reason. Maybe in conbination with a heat gun to increase the thermal shock. For poking EHT I suggest large knitting needles, even if not EHT certified. That's why my long-late Dad had one in his toolkit, anyway... Mike. |
| Cursitor Doom <curd@notformail.com>: Mar 03 01:54PM On Tue, 3 Mar 2020 10:59:59 -0000, Mike Coon <gravity@mjcoon.plus.com> wrote: >conbination with a heat gun to increase the thermal shock. >For poking EHT I suggest large knitting needles, even if not EHT >certified. That's why my long-late Dad had one in his toolkit, anyway... I have a couple of 30kV high voltage AVO probes with long spikes for that sort of thing if necessary. Anyway, I didn't need the spray. It looks like the problem is/was an insufficiently snug edge connector to the motherboard. These are pretty much identical to the ones you see in desktop computers; same pitch etc. I took the suspect board out and cleaned it's edge connections with IPA but noticed on re-insertion there is no positivity about the fit whatsoever unlike the other boards I've removed and re-fitted before. You cannot really tell whether it's seated fully by feel. Not good. Anyway, problem's gone away -- but for how long, who knows? |
| John Robertson <spam@flippers.com>: Mar 03 08:36AM -0800 On 2020/03/03 1:20 a.m., Cursitor Doom wrote: > The appeal here is that there's no mechanical stress being applied > except in the immediate area of application and I've already found > that this fault is unusually sensitive to any form of physical stress. CRT tube cathode is typically under 200VDC, not exactly EHV, and the screen may run in at 400V. Focus is likely 2K or so, but that is why one stocks a HV meter. The 'scope is for monitoring the cathode, not the EHT. John :-#)# |
| Arlen Holder <arlen.george.holder@is.invalid>: Mar 03 04:07AM > "After replacing the battery, Geekbench showed that the scores had nearly > doubled." > <http://nymag.com/selectall/2017/12/is-apple-slowing-down-iphones-with-aging-batteries.html> UPDATE: Notice the Apple apologists _hate_ what Apple does so much that they'll endlessly deny even well verified facts that Apple publicly admitted! <https://i.postimg.cc/BQZ9hZg1/crime00.jpg> See also this thread today with an important update, thanks to JF Mezei: o *Apple agrees to settle class action in US over throttling $500M* <https://groups.google.com/forum/#!topic/misc.phone.mobile.iphone/BR4edQQisYg> === === === Quoted verbatim from that thread: === === === <https://www.nytimes.com/2020/03/02/technology/apple-iphone-lawsuit-settlement.html> Quote: <<"Eligible devices include any iPhone 6, 6s Plus, 7, 7 Plus and SE that ran iOS 10.2.1 or later, or any iPhone 7 or 7 Plus that ran iOS 11.2 or later. Eligible customers had to live in the United States, and their devices had to run the given software before Dec. 21, 2017.">> $25 per qualified phone. === === === Quoted verbatim from that thread: === === === This is the thread that broke the news of Apple's secret, drastic, and permanent CPU throttling due to inherently poor power-management design... o *Report says Apple 'Powerd' code secretly slows your iOS device down to trick you into buying a new device* <https://groups.google.com/d/msg/misc.phone.mobile.iphone/GdEtzzrc9F0/z57KTsmWAQAJ> See also this thread where Apple publicly admitted to the crime of intentionally secretly lowering the life of essentially the same set of iPhones: <https://i.postimg.cc/BQZ9hZg1/crime00.jpg> o *Apple agrees to pay 25 million euros fine as Apple admits "Apple committed the crime of deceptive commercial practice by omission"* <https://groups.google.com/forum/#!topic/misc.phone.mobile.iphone/l6gAjvW6aqQ> See also this thread, where JF Mezei seems to be updating as news comes in: o *Quebec class action goes ahead (battery gate)* <https://groups.google.com/forum/#!topic/misc.phone.mobile.iphone/jmDdZewelrk> Bear in mind, Apple essentially lied to Congress (as in "I didn't inhale") when they said in their coverup that iPhone throttling wasn't "as" necessary on the later phones, where, the facts prove Apple added throttling in _every_ subsequent iOS release since! o *Every iPhone CPU from the iPhone 6 to iPhone 7 were throttled, then iPhone 8 to iPhone X were throttled & now the iPhone XS, iPhone XS Max & iPhone XR get throttling software* <https://groups.google.com/forum/#!topic/misc.phone.mobile.iphone/Mzh1IvniDr8> In addition, Apple clearly lied in their subsequent coverup, with respect to the fact they secretly modified the release notes well _after_ the fact. o *Evidence Apple cleverly manipulated iOS release notes on "power management" after the fact* <https://groups.google.com/d/msg/misc.phone.mobile.iphone/KXhivHMvrlY/OuV1lgS8AgAJ> Given the speeds were secretly cut in _half_ by Apple... o Apple throttled your iPhone by cutting its speed almost in HALF! <https://groups.google.com/d/msg/misc.phone.mobile.iphone/l79Xb6qx8Fs/08j5ImhABQAJ> And given that Apple's design causes premature replacement of millions of batteries yearly... o *FACTS: Apple replaced 11 million batteries last year (normal replacement is ~1.5 million batteries per year)* <https://groups.google.com/d/msg/misc.phone.mobile.iphone/8Vica_VqdT4/TzFfpZqVBwAJ> How is prematurely replacing millions of batteries yearly a good thing for the environment? o *All new iPhones might be forced to have a removable battery (Android too)* <https://groups.google.com/forum/#!topic/misc.phone.mobile.iphone/4Ja4FP5eL5s> How is intentionally shortening iPhone life good for the environment? -- Notice the Apple apologists _hate_ what Apple does so much that they'll endlessly deny even well verified facts that Apple publicly admitted! |
| Fox's Mercantile <jdangus@att.net>: Mar 02 10:34PM -0600 On 3/2/20 10:07 PM, Arlen Holder wrote: [ Nothing of any merit as usual. ] Go fuck yourself you useless waste of bandwidth. -- "I am a river to my people." Jeff-1.0 WA6FWi http:foxsmercantile.com |
| "pfjw@aol.com" <peterwieck33@gmail.com>: Mar 03 04:12AM -0800 Vos non potestis figere stultus. Ní féidir leat a shocrú dúr. Man bekommt Dummheit nicht in den Griff. Το κάρμα είναι σκύλα. Tu ne peux pas réparer stupide. .لا يمكنك إصلاح غبي That about covers it, using all the languages I have "interacted with" over time, one way or another. Peter Wieck Melrose Park, PA |
| Nife Sima <gorplop@sdf.org>: Mar 02 09:38PM +0100 On 29.02.2020 18:26, Stu jaxon wrote: > Hi Group, Can someone help please, I'm working on a HISENSE 161364 POWER SUPPLY BOARD FOR model #40K360MN. no vlotage going to the backlights. I ordered the wrong board. The old board # is 161364, I ordered 161565.. I looked on both boards all the components seem to match, except the two filter caps, on the original board they are 450v 68uf, and the new board are 250v 68uf, so the question is.. can I exchange the two caps from old to new board. ? and would have to change the eprom, they are both matching as well don't know if they are programmed differently.? Wait! 450V vs 250V? What mains input are the new and old boards? How did you make sure *all* the components are identical? -- Nife Sima - the lower earth crust |
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