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Cursitor Doom <curd@notformail.com>: Jul 15 10:34AM On Thu, 14 Jul 2016 18:53:25 -0700, Jeff Liebermann wrote:   > regulator doesn't like a light load, kindly put a load resistor across > the 12V line and see if the situation improves. (Hint: When > troubleshooting, I like to do easy things first. A resistor is easy).   I did try that resistor idea before, but it didn't make any difference. But it was 1500 ohms, so maybe too light to produce the desired effect.   I've now installed a 100uF electroylic in parallel with the existing 100nF ceramic on the output, but it's made no difference I'm sorry to say.   > have this exact problem, but might not appreciate having some holes > blown in the IC's insulating layers. It's not easy to test for this, so > just replace the LM317T with one that has a good chance of working.   OK, your 'partially-blown theory' is noted. I'll try replacing it if all else fails as it's a bit tricky to get at.     > I'm also wondering if there's something odd about your construction > methods.   Yeah, I'm aware of the importance of good layout so we can't attribute the issue to that in this instance.   > hurt to check. Insert a 1 ohm resistor in the PS line and measure the > drain with a differential input scope (i.e. using 2 scope probes). Look > for giant current spikes and high freq oscillations, that don't belong.   I do actually have a current probe somewhere. Anyway, before I try any of that, I'm going to give these earlier suggestions from you and others a chance:   a) Load it down with a lower-value resistor in parallel with the electrolytic.   b)Insert bypass cap to the 'adjustment' pin   There is also the more remote poss that the regs I have a fakes. There are fake regs out there and I've had some myself off Ebay, but I'd be surprised if that were the case here since all the fakes I've heard about can barely provide a few tens of miliamps. I shall order some fresh ones from Farnell in a moment or two, though, just so I have *known* good reference regs for comparison purposes.

Bruce Esquibel <bje@ripco.com>: Jul 15 10:35AM > 9.3mA. The bench PSU doesn't have any issues powering this board.   > When connected to PSU that uses the LM317, however, it draws 3mA and the > voltage across it drops to around 6V.   If the current requirements are that low, why don't you use something like the LM7812 instead of the 317?   They are far simpler to use, aren't as flakey as the 317 and about as cheap.   Unless the supply the 317 is in is needed to be voltage adjustable or high current (or higher than a LM78xx can produce), you'll save a lot of hair pulling using the LM7812.   -bruce bje@ripco.com

Cursitor Doom <curd@notformail.com>: Jul 15 10:59AM On Fri, 15 Jul 2016 10:35:52 +0000, Bruce Esquibel wrote:   > high current (or higher than a LM78xx can produce), you'll save a lot of > hair pulling using the LM7812.   > -bruce bje@ripco.com   It really doesn't need to be adjustable, but if I'm going to swap to a different device I'd really rather get something with a bit more 'headroom' than these 40V max regs, since I'm inputting ~37V. I wasn't aware that the 317 was regarded as flaky but bow to your superior knowledge of the subject!

Cursitor Doom <curd@notformail.com>: Jul 15 01:30PM On Thu, 14 Jul 2016 18:53:25 -0700, Jeff Liebermann wrote:   > Incidentally, it is possible to damage an IC to the point where it still > functions, but no in the manner commonly expected.   This is now the front-running suggestion from tests I've just carried out. Confirmation one way or the other in a few hours.

"Michael A. Terrell" <mike.terrell@earthlink.net>: Jul 15 07:50AM -0400 Jeff Liebermann wrote: > lights, glow in the dark cable, coiled cords, etc. Whatever you buy, > get an assortment. Also, buy a different charger, which I think is > causing the problem.     Dollar Tree stores have recently started selling the flat cables for $1 plus sales tax, and in a half dozen colors. There are a half dozen of their stores in my area. :)

ohger1s@gmail.com: Jul 15 04:18AM -0700 > video card too? Could the flaky power supply be affecting the video > card too? > Eric   Since you've already ordered a new power supply I wouldn't go any further until that's installed. If the supply is sluggish or inop when cold, it most likely has high esr electrolytics. Even when warm enough to allow function, they still allow sag and ripple on the outputs which can upset whatever is connected to it. Good chance everything gets fixed with the new supply.

jurb6006@gmail.com: Jul 15 12:11AM -0700 >"Holding the meter near an analogue CRO screen will reveal if this >is the case. "   Ha. Try finding one these days. I got a couple laying around not hooked up. Gave Ma one when her XBR took a shit and it is CRT. But I bet if I walked up and down the street and banged on people's door I would have to walk miles before finding anyone with a CRT based TV.   Years ago people were already laughing saying "TVs are flat now, stupid".   So how do we indicate if something is magnetically charged with the lack of color CRTs or whatever ? I was thinking a guitar string but how do we know it itself is not magnetised ? I fit is used it has spent alot of time right in front of a pretty strong magnet. See if it attracts to other strings ? I guess that might work.   I think this guy needs to wrap wire around those jaws, and out of phase so they don't blow the thing out (or disconnect it) and just demagnetize it with a stepdown transformer to something reasonable so as not to blow the variac either and give it a good douche of 50 or 60 Hz, depending. If the bogus reading goes away we know what happened.   Now if it doesn't, the plot thickens.

jurb6006@gmail.com: Jul 15 12:15AM -0700 I fucked up the quoting on that.

MJC <gravity@mjcoon.plus.com>: Jul 15 09:26AM +0100 In article <b4a7ee92-e039-42f3-846b-9bf7dd22bce8@googlegroups.com>, jurb6006@gmail.com says...   > So how do we indicate if something is magnetically charged with the > lack of color CRTs or whatever ?   Because now we have GPS no-one has a Boy Scout compass any more?   Mike.

Phil Allison <pallison49@gmail.com>: Jul 15 02:45AM -0700 > >"Holding the meter near an analogue CRO screen will reveal if this > >is the case. "   > Ha. Try finding one these days.     ** Most techs have one - I own four.   Analogue CROs are what we all used until DSOs with LCD screens came along.   The trace is very sensitive to a magnetic field.       .... Phil

jeanyves <jeanyves@nowhere.com>: Jul 15 09:36AM +0200 On 2016-07-15 06:23:19 +0000, Baron said:   > than the old halogen bulbs. So much so that we now tend to turn on > only half of the 12 lights in the kitchen. The bathroom uses all > six.   and forgot to say the GU10 is far more easy to handle than the MR16 ... I replaced all my ceiling bulbs 5-6 years ago, still none has died for now. and if one dies, it's easy to find the same and replace it the only thing will be to struggle with the color of the light to find something similar to the others may be I will have to replace a whole room at a time !   --   Jean-Yves.

N_Cook <diverse@tcp.co.uk>: Jul 14 09:24AM +0100 This is a Samsung n102 notebook. 2 contacts to the single ring contact in the chassis socket. So the small one presumably an insertion switch ,for whatever reason, and the other for current. In the process of bending the arm wiht a needle, the contact end , at the open end of the socket, sprung out from behind the lip. Luckily while bending out while pressing down on the tip to try and get it back in , it reinserted behind the lip. So next time , while bending the arm radially inwards, hold the tip in wiht a jeweller screwdriver blade. Leaves what is the function of this switch, just enables/disables the 2 colour charging LED and display light level setting ? locks out the inboard charging after an unknown time after loss of switch contact for some unknown reason? I never thought to check the pc battery charge gizmo, just noticed the LED going on and off and display backlight dipping/brightening.

Jerry Peters <jerry@example.invalid>: Jul 14 08:04PM >> gnd, the inner side of the barrel is +19.5 V, the center pin is some >> resistor or something that classifies the power supply's capacity.   > More than just a resistor, I think it's a 1-wire bus.   But whatever it is, it's not too complex. My non-Dell laptop supply has a special adapter for Dell laptops. It's a bit larger that the other plugs and it does fool the laptop into charging.

Jeff Liebermann <jeffl@cruzio.com>: Jul 13 05:19PM -0700 On Wed, 13 Jul 2016 16:28:02 -0700, John Robertson <spam@flippers.com> wrote:   >> down to WD40.   >I think we will call this Jeff's Law. >John ;-#)#   Sorry but that name is already taken, at least in Florida: <http://cyberbullying.org/jeffs-law> Also, such an association might tarnish my reputation. Think of something else or something better.         -- 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

Phil Allison <pallison49@gmail.com>: Jul 13 09:57PM -0700 Jeff Liebermann wrote:   > Tarnish does not always result from the sole effects of > oxygen in the air. For example, silver needs hydrogen sulfide > to tarnish, although it may tarnish with oxygen over time.   ** The Wiki does not actually say that *silver oxide* is formed on bare silver, in air at room temp.   Other Google references say that in rare cases, silver chloride can form but make no mention of silver oxide.     .... Phil

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