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Cursitor Doom <curd@notformail.com>: Mar 05 02:48PM https://www.sparkfun.com/products/11005   Replace the existing connector with a BNC, add a bit of series resistance and you have a *very* cheap current probe for your scope.

John Larkin <jjlarkin@highlandtechnology.com>: Mar 05 07:44AM -0800 On Sun, 5 Mar 2017 14:48:51 -0000 (UTC), Cursitor Doom   >https://www.sparkfun.com/products/11005   >Replace the existing connector with a BNC, add a bit of series resistance >and you have a *very* cheap current probe for your scope.   I have a clamp-on ammeter that pretty much does that, although it just indicates amps, and doesn't allow waveform snooping. 60 Hz waveforms aren't terribly interesting.   My real problem with current measurement is DC, on PC boards. We want to know how much current, say, an FPGA is using. Sometimes I include current shunts in a layout, but sometimes I don't.   One can use existing switcher inductors as current shunts. I wish I had a PCB trace current probe, but that's probably not posssible. You can measure millivolt and microvolt drops across traces and vias.         --   John Larkin Highland Technology, Inc   lunatic fringe electronics

Cursitor Doom <curd@notformail.com>: Mar 05 04:18PM On Sun, 05 Mar 2017 07:44:18 -0800, John Larkin wrote:   > I have a clamp-on ammeter that pretty much does that, although it just > indicates amps, and doesn't allow waveform snooping. 60 Hz waveforms > aren't terribly interesting.   Indeed they're not. But your meter is presumably *only* designed for use at 60Hz, I would imagine. Hook it up to a 100Hz signal and you'll see nothing at all in all probability. ;-)   > One can use existing switcher inductors as current shunts. I wish I had > a PCB trace current probe, but that's probably not posssible. You can > measure millivolt and microvolt drops across traces and vias.   Do they even exist? That would be amazing but no doubt *way* beyond what I can justify to splash out on as a mere hobbyist.

"Benderthe.evilrobot" <Benderthe.evilrobot@virginmedia.com>: Mar 04 09:07PM <pfjw@aol.com> wrote in message news:342bcce6-1434-4f63-bff1-e785e7383385@googlegroups.com... > foam speaker surrounds of recent memory.   > I use an acid-free neutral-formula flexible hot-melt for the purpose. I > source from AdTech.   Some manufacturers use hot melt - but some power components get hot enough to melt it.   A range of IBM VGA monitors had clusters of tall electrolytics in the PSU with blobs of RTV joining the tops together.   I'm not entirely convinced it served the intended purpose and it was a PITA cutting it away when the caps had to be replaced and/or tested.

"Benderthe.evilrobot" <Benderthe.evilrobot@virginmedia.com>: Mar 04 09:09PM "N_Cook" <diverse@tcp.co.uk> wrote in message news:o9cpc2$er4$2@dont-email.me... >> stuff and the leads completely eaten away.   > sorry wrong followup. > You failed to mention it going conductive   That was pretty much implied by it becomes corrosive.

"Benderthe.evilrobot" <Benderthe.evilrobot@virginmedia.com>: Mar 04 09:14PM "Phil Allison" <pallison49@gmail.com> wrote in message news:1879ee73-2e28-400f-ae1e-19e548cb5609@googlegroups.com...   > ** You got proof of that ?   > In any case, the black tarnish on silver exposed to air is Silver > Sulphate - which is an insulator.   It would be sulphate if exposed to sulphuric acid.   The sulphide is mainly produced by a component of car exhaust - or your farts if you've been eating eggs.   Catalytic converters stop your silverware going black (or make it go black even quicker - I can't remember which) - and kill thousands of asthma sufferers.

Phil Allison <pallison49@gmail.com>: Mar 04 06:05PM -0800 > True for sterling (.925) silver. > Fine silver - what is deposited by electroplating - does not form > compounds with sulphur at anything near normal room temperatures.   ** As you seem to be the only person in the world who thinks that - you need to post a link to back it up.   Do you know what "black leg" corrosion is ?   Commonly seen on the leads of small signal transistors made in Japan in the 70s. It often results in the device going noisy or failing completely. Marantz stereo amps were notorious for it.       .... Phil

John Robertson <spam@flippers.com>: Mar 04 06:29PM -0800 On 2017/03/04 6:05 PM, Phil Allison wrote:   > Commonly seen on the leads of small signal transistors made in Japan in the 70s. It often results in the device going noisy or failing completely. Marantz stereo amps were notorious for it.   > ..... Phil   Hey Phil,   Can you provide a link to more in depth discussion on your black leg corrosion? I did a quick search and could only find one reference, and it merely said watch out for 'black leg corrosion'?   I have run into a lot of Namco branded ICs from Japan, made in the late 70s that have this problem...   Thanks!   John :-#)#   -- (Please post followups or tech inquiries to the USENET newsgroup) John's Jukes Ltd. 2343 Main St., Vancouver, BC, Canada V5T 3C9 (604)872-5757 or Fax 872-2010 (Pinballs, Jukes, Video Games) www.flippers.com "Old pinballers never die, they just flip out."

Phil Allison <pallison49@gmail.com>: Mar 04 07:17PM -0800 John Robertson wrote:   > Can you provide a link to more in depth discussion on your black leg > corrosion? I did a quick search and could only find one reference, and > it merely said watch out for 'black leg corrosion'?   ** Not much to be found on the net, but something most service techs have seen.   Bit like the "yellow glue" problem that has plagued countless items and still is.   > I have run into a lot of Namco branded ICs from Japan, made in the late > 70s that have this problem...   ** It's got be due to silver plating the leads.     .... Phil

John Robertson <spam@flippers.com>: Mar 04 10:42PM -0800 On 2017/03/04 7:17 PM, Phil Allison wrote:   >> I have run into a lot of Namco branded ICs from Japan, made in the late >> 70s that have this problem...   > ** It's got be due to silver plating the leads.   I'm sure they thought that silver plating was a good idea, instead of planned obsolescence.     > ..... Phil   Thanks,   John :-#)#   -- (Please post followups or tech inquiries to the USENET newsgroup) John's Jukes Ltd. 2343 Main St., Vancouver, BC, Canada V5T 3C9 (604)872-5757 or Fax 872-2010 (Pinballs, Jukes, Video Games) www.flippers.com "Old pinballers never die, they just flip out."

"pfjw@aol.com" <pfjw@aol.com>: Mar 05 04:57AM -0800 On Saturday, March 4, 2017 at 10:17:05 PM UTC-5, Phil Allison wrote:   > ** It's got be due to silver plating the leads.   > .... Phil   No, Phil, it is not *DUE* to the silver plating on the leads, nor is the silver plating on the leads even contributory to the primary failure, though it does contribute to the visual results.   Let me start over as you clearly need the little-steps-for-little-feet approach.   a) Silver electroplating does not adhere well to anything but copper, low-tin bronze and very low zinc brass. b) So, most materials to be silver-plated are first flash-plated with pure copper. Otherwise the failure of the silver-plate due to simple peeling would be quick and fast. c) Over time, the different coefficients of expansion, simple age, heat/cool cycles and other environmental factors cause the copper plating to crack, microscopically, initially. d) At which point, electrolysis takes place between the copper and base-metal of the lead/pin/whatever. e) The first product of failure is CuO - because typically the substrate (base metal) would be sacrificial to the copper, in this case, the copper becomes sacrificial to the silver. f) CuO is a black semi-conductor, still (very rarely) used in very heavy duty rectifiers. g) Silver reactions with sulphur do not produce a grainy material, Even extensive reactions. h) Copper oxides, with the fine silver still attached, are grainy. The fine silver will be entirely covered by the copper oxide, but will not actually react itself.   So, that you state something *MUST* be due to something else does not make it so. Jewelers and metalsmiths have been exploiting this phenomenon for many years and it is very well understood. You need to learn that there is an entire world outside your cave.   Peter Wieck Melrose Park, PA

Phil Allison <pallison49@gmail.com>: Mar 05 05:04AM -0800 > No, Phil, it is not *DUE* to the silver plating on the leads, > nor is the silver plating on the leads even contributory to the > primary failure, though it does contribute to the visual results.   ** Shame you have NO links whatever to back up this arrant nonsense. > Let me start over as you clearly need the little-steps-for-little-feet > approach.   ** Go fuck yourself - asshole.   Wieck is a psychotic, raving lunatic.   I snipped his manic ravings.   To spare gentle the readers here.       .... Phil

"pfjw@aol.com" <pfjw@aol.com>: Mar 05 05:53AM -0800 file:///C:/Users/Peter/Downloads/corrosion_of_silver_plated_copper_conductor.pdf   Phil:   It's a big world out there - first link I found, and pretty much describes the situation nicely.   But, I am sure you will spin it in your own inimitable manner.   Peter Wieck Melrose Park, PA

vjp2.at@at.BioStrategist.dot.dot.com: Mar 04 08:42PM Is it advisable to put duct tape over the SD slot to keep it from popping out     - = - Vasos Panagiotopoulos, Columbia'81+, Reagan, Mozart, Pindus, BioStrategist http://www.panix.com/~vjp2/vasos.htm ---{Nothing herein constitutes advice. Everything fully disclaimed.}--- [Homeland Security means private firearms not lazy obstructive guards] [Urb sprawl confounds terror] [Phooey on GUI: Windows for subprime Bimbos]

N_Cook <diverse@tcp.co.uk>: Mar 04 09:21PM > ---{Nothing herein constitutes advice. Everything fully disclaimed.}--- > [Homeland Security means private firearms not lazy obstructive guards] > [Urb sprawl confounds terror] [Phooey on GUI: Windows for subprime Bimbos]   Just 1 SD , or all of them?

Michael Black <et472@ncf.ca>: Mar 04 05:55PM -0500

avagadro7@gmail.com: Mar 05 05:46AM -0800 spray cards n slot with CRC electronics clear from Walmart n hardware   the card is not engaging ...also prob your insertion is not straight forward ie tilt runs up n over engage mechanism.   my Marantz pmd has a door problem. twisted 3M electrical tap into loop forced over case holds door shut after slipping a quarter between door n tape loop.   hitech

"Michael A. Terrell" <mike.terrell@earthlink.net>: Mar 04 01:29PM -0500 >> "You can post public files to a private Google Drive, which is free, > All you have to do is mark the file as public."   > Understood, but what to do with files that were posted year(s) ago and now the URL is invalid and you cannot go back and edit the post ?     I keep copies of anything I put up to share.     > And that applies to every forum on the net, not just Usenet.   > You can say "Whaddya want for nothing" and really that is true. And that is why I am not going to use Google Drive. If you are not the customer, you are the product.     I really don't care what you won't use. You won't use Google Drive, you won't use Yahoo groups for help to repair test equipment.     > Damn, I never though I would insist on paying. My Uncle would probably kill me but he is dead now. One day I might write of him, but not today.     Pay, if you want to but even paid sites disappear, or drop features.   -- Never piss off an Engineer!   They don't get mad.   They don't get even.   They go for over unity! ;-)

jurb6006@gmail.com: Mar 05 02:51AM -0800 Well then go back to your Usenet posts from ten fucking years ago and change those URLs.   You cool with that ?

Bob Engelhardt <BobEngelhardt@comcast.net>: Mar 04 10:09PM -0500 On 3/3/2017 11:31 AM, Jeff Liebermann wrote: > On Fri, 03 Mar 2017 01:46:08 -0500, Bob Engelhardt wrote:   >> Unless my Kill-a-watt is wonky.   > That's a possibility. I have several kill-a-watt meters. ...   I checked my Kill-a-watt against my Fluke "True RMS" clamp-on. They read the same current, so that gives me a lot more confidence in the Kill-a-watt.   Now, for the "I'm feeling really stupid" part: in the maze of cables under my desk, I had put the Kill-a-watt on the wrong one! I was measuring the power on everything: PC, printer, modem, etc.   When I used the right cable & measured just the PC, the power was 155W+-. Versus the 200W previously. So my PSU efficiency is 33%+- (54/155). Better than the previous/wrong 25%, but not dramatically so.   Thanks to all the commenters.   Bob

"Phoena Greene" <raeanne.is@ratchet.hoe>: Mar 04 02:39PM -0800 <oldschool@tubes.com> wrote in message news:t9mbbc5418km67mllujvn066i1utpo7uma@4ax.com...   > What's the scoop on this?   > (If I had read this before placing the order, I would not have placed > this order).   I don't remember paying any tariffs or taxes on a Android TV box that I bought from China off Ebay. I bought it to replace a Sony Blu Ray Player that I murdered with a hammer. The Blu ray player decided to piss me off and it wasn't it's lucky day. Just had to wait two weeks for it to ship from China to my door.

"Phoena Greene" <raeanne.is@ratchet.hoe>: Mar 04 02:13PM -0800 "Benderthe.evilrobot" <Benderthe.evilrobot@virginmedia.com> wrote in message news:cH_tA.13664$e%2.11566@fx41.am4... > and not "copy", and I double checked that the top bar says "moving".   > This looks a lot like a bug in Lubuntu!   > Thanks for any help.   I think just about everything in Linux only half works.

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