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Phil Allison <pallison49@gmail.com>: May 07 12:02AM -0700 Jeff Liebermann wrote:     > Those are the classic symptoms of a defective electrolytic capacitor.   ** Or several OR a dry solder joint or many of them.     > <http://802.11junk.com/jeffl/Electrolytic-cap-test/> > Simple setup: > <http://802.11junk.com/jeffl/Electrolytic-cap-test/test-setup.jpg>   ** You went to lot of trouble to see the obvious.   All I did was try a few 450V electros, heat them with a hot air gun until they were darn uncomfortable to hold and note that in every case the ESR reading had plumeted by 5 to 10 times.   Then I found some graphs on-line that backed up the finding.     > There are a number of different ESR meters available.   ** I use the same one as in your pics - the Bob Parker design. He lives not far from me and we have conversed about that an many other electronics matters.   Have you tried your meter to test the ESR of cells ?   Easy to tell if a Lithium memory cell is good or not - also good on NiCds, NiMH and alkalines.   Also reads low value resistors, even if there is an inductor or transformer winding across one.     .... Phil

N_Cook <diverse@tcp.co.uk>: May 07 10:32AM +0100 > the markings off of any device with more than three leads. > Thanks, > Eric   ISTR once coming across a failed zener in a smps causing this works when warm syptom

N_Cook <diverse@tcp.co.uk>: May 07 10:35AM +0100 > the markings off of any device with more than three leads. > Thanks, > Eric   I've seen a dot on ICs signifying PbF

jeanyves <jeanyves@nowhere.com>: May 07 02:18PM +0200 > the markings off of any device with more than three leads. > Thanks, > Eric   lots of esr meters to choose from : to build or to buy http://kripton2035.free.fr/esr-repository.html   --   Jean-Yves.

"pfjw@aol.com" <pfjw@aol.com>: May 07 05:43AM -0700 > When it has that plastic sheath over it, the bulging top does NOT indicate it is bad.   Ummmm..... Not on my watch! I do keep an ESR meter, and I also keep a cap-tester that can test at actual operating voltages and in AC or DC. ANY physical indications of ANY nature other than friction or impact will get a cap changed. And every electrolytic in an item that affects the perceived problem will get tested with that ESR meter. When in doubt, change it out.   The problem with swelling is that it may not be affecting the cap *today*. And the actual stresses on the cap may be well below its rating. But when (not if) it fails, it will be at the most awkward possible moment and take much with it. Murphy's Law. Caps, even very good ones, are much cheaper than the time it takes to replace them. Just keep that in mind.   Peter Wieck Melrose Park, PA

"pfjw@aol.com" <pfjw@aol.com>: May 07 05:47AM -0700 On Saturday, May 7, 2016 at 8:18:08 AM UTC-4, jeanyves wrote: > http://kripton2035.free.fr/esr-repository.html   > --   > Jean-Yves.   I keep the "Blue" meter. Easy to use and as tested against others, quite accurate.   Peter Wieck Melrose Park, PA

DaveC <not@home.cow>: May 07 08:34AM -0700 > corresponding cap in the other channel when you find a bad one, or even weak > one (significant ESR compared to Xc) it does no good to just change them all > arbitrarily.   Sure it does. If the problem is with one of these caps, changing them arbitrarily FIXES the problem.   "Penny wise, pound foolish." Yes, you're right, finding the ONE cap that is the cause is technically proficient. But just to say "I found the culprit!" does not help the customer (or yourself, if it's you). The unit will be back on your bench very soon if you don't replace all electros now, if you find one or more below spec.

DaveC <not@home.cow>: May 07 08:54AM -0700 > Simple setup: > <http://802.11junk.com/jeffl/Electrolytic-cap-test/test-setup.jpg>   Bob Parker / Dick Smith / Silicon Chip meter!!!   Bob is the original designer of this meter. Last I looked Bob was still giving help to builders of his kit.

DaveC <not@home.cow>: May 07 08:56AM -0700 > Bob Parker / Dick Smith / Silicon Chip meter!!!   > Bob is the original designer of this meter. Last I looked Bob was still > giving help to builders of his kit.   http://members.ozemail.com.au/~bobpar/esrmeter.htm

"Andy" <N@n.com>: May 07 01:32AM -0400 Good idea will give me something to do later:)     -- AL'S COMPUTERS "Mark Zacharias" <mark_zacharias@sbcglobal.net> wrote in message news:A8ZWy.8968$l93.1390@fx42.iad...

"Andy" <N@n.com>: May 07 01:34AM -0400 As far as i know unless it was sold again first alert is owned or WAS OWNED by kiddie   -- AL'S COMPUTERS "Jeff Liebermann" <jeffl@cruzio.com> wrote in message news:mhapibdmjsk0egccum8vm5pbat1915a1ol@4ax.com...

jurb6006@gmail.com: May 07 06:09AM -0700 >"Glass cored resistors cause an increase in current and consequently >the >potential for damage"   I remember a video on the internet about having some "fun" with a microwave. Normally you put glass in a microwave it is unaffected. Well they took a torch to it and heated it up first and then it was definitely affected by microwaves. Before that I never knew glass becomes conductive at high temperatures.

Jeroni Paul <JERONI.PAUL@terra.es>: May 07 05:21AM -0700 N_Cook wrote: > inside. > The neons run at 24 deg C over ambient, so perhaps 5 or 6 would be > better if more than a temporary fudge.   I have been looking for a practical/cheap solution for the same problem on a DELL 1707FPt computer display. It has four backlight tubes two at the top and two at the bottom. One of them was cracked and very darkened inside, the rest were fine. Problem is the inverter is not happy without a load on that output, runs for one second and shuts down. I tried three 3W resistors in series adding 120K and it works fine, yet the resistors get quite hot. The missing tube is barely noticeable, it just causes the top 1/3 of the srceen to be slightly darker but goes mostly unnoticed. I would be happy to make it work with three tubes, installing the resistors permanently is one solution but I wondered if the inverter could be modified somehow to disable or ignore that output. The inverter uses a transformer for each pair of tubes so not sure if there is anything that can be done.

philo <philo@privacy.net>: May 07 01:54AM -0500 On 05/06/2016 10:48 PM, Paul in Houston TX wrote: >> drive was installed.   >> Otherwise it was loose pins   > Yea, I agree. Should have made that clear in my post.       At any rate, thought I've seen burned or over-heated connections, I've never seen one go up in smoke.

legg <legg@nospam.magma.ca>: May 07 12:21AM -0500 On Fri, 06 May 2016 16:34:10 -0400, Micky   >>>On Wed, 04 May 2016 07:51:16 -0500, legg <legg@nospam.magma.ca> wrote:   >>>>On Tue, 03 May 2016 23:06:33 -0400, Micky >>>><NONONObobbyburns1111@gmail.com> wrote: <snip> >>something detecting false levels on the mic, or a failing to return to >>the Rx from Tx states ~flakey mike,   >There are Rx and Tx states in a wired phone??   Depends on what chips are used. If it has wireless handsets in the out-of-the-box package, it could use the same parts or firmware for cost reasons - just using the wires to sub out the battery. Who knows.   RL

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