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DaveC <not@home.cow>: Mar 21 11:27PM -0700 3-terminal (well 4, including the tab) SOT-89/TO-243 (4.5 x 2.5 mm) package.   Marked: 2108A 2216/36   Thanks.

DaveC <not@home.cow>: Mar 21 10:30AM -0700 The LED in my flashlight is blinking (2/sec). It's not the support circuitry (constant current): the voltage across the LED is constant 4v. I presume it's a failure mode of the LED. It happens immediately upon power-on.   http://imgur.com/a/rIRDG   The form-factor is close to a 5x5mm (h x diam). Standard through-hole leads.   But it's a pretty high-intensity one. Don't know what makes it so, but I classify anything with a yellow square visible in the center as "high-intensity". Maybe not technically accurate, but there you are.   What I've found so far is either a standard 5mm LED but not very bright, or SMD types requiring heat sinks.   It's a great little light, and I've not found anything as small, long-lasting, with single AA that I like as much. And this is a learning experience, so there's that.   Any pointers to a suitable replacement LED would be appreciated.   Thanks.

"pfjw@aol.com" <pfjw@aol.com>: Mar 21 01:10PM -0700 On Monday, March 21, 2016 at 1:30:08 PM UTC-4, DaveC wrote:   > experience, so there's that.   > Any pointers to a suitable replacement LED would be appreciated.   > Thanks.   So, its mot a Maglite? That about covers the "suitable replacement" question. That light was never meant to be serviced, and so your best bet in terms of time/cost/effort, together with the inevitable PITA factor is to simply replace the light altogether.   Peter Wieck Melrose Park, PA   p.s.: Only Maglites permitted in this household.

"Gareth Magennis" <soundserviceleeds@outlook.com>: Mar 21 08:33PM wrote in message news:e658aab4-4e65-4e77-8c26-0937bb55aceb@googlegroups.com...   On Monday, March 21, 2016 at 1:30:08 PM UTC-4, DaveC wrote:   > experience, so there's that.   > Any pointers to a suitable replacement LED would be appreciated.   > Thanks.   So, its mot a Maglite? That about covers the "suitable replacement" question. That light was never meant to be serviced, and so your best bet in terms of time/cost/effort, together with the inevitable PITA factor is to simply replace the light altogether.   Peter Wieck Melrose Park, PA   p.s.: Only Maglites permitted in this household.         I used to use Maglites, til LED torches came on the scene.   No way I would buy a Maglite now.       Gareth.

Bob Engelhardt <BobEngelhardt@comcast.net>: Mar 21 05:00PM -0400 On 3/21/2016 1:30 PM, DaveC wrote: > ... the voltage across the LED is constant 4v. > ... with single AA ...   So it has a boost SMPS?

Cursitor Doom <curd@notformail.com>: Mar 21 09:38PM > p.s.: Only Maglites permitted in this household.   Make good billy clubs, the larger ones. :->

"Gareth Magennis" <soundserviceleeds@outlook.com>: Mar 21 10:56PM "Gareth Magennis" wrote in message news:xUYHy.69876$jz.53865@fx41.am4...       wrote in message news:e658aab4-4e65-4e77-8c26-0937bb55aceb@googlegroups.com...   On Monday, March 21, 2016 at 1:30:08 PM UTC-4, DaveC wrote:   > experience, so there's that.   > Any pointers to a suitable replacement LED would be appreciated.   > Thanks.   So, its mot a Maglite? That about covers the "suitable replacement" question. That light was never meant to be serviced, and so your best bet in terms of time/cost/effort, together with the inevitable PITA factor is to simply replace the light altogether.   Peter Wieck Melrose Park, PA   p.s.: Only Maglites permitted in this household.         I used to use Maglites, til LED torches came on the scene.   No way I would buy a Maglite now.       Gareth.           Oops, just discovered Maglite do LED's.   My old MiniMaglite wouldn't do 2 gigs on one set of batteries, and I would regularly have to replace the bulb too, and the switch would always need maintenance. Very expensive running costs, very time consuming, but good for hammering in nails etc.     Gareth.

"pfjw@aol.com" <pfjw@aol.com>: Mar 21 05:01PM -0700 Maglite makes LED units as well. The also stand behind their products....   Peter Wieck Melrose Park, PA

John Larkin <jjlarkin@highlandtechnology.com>: Mar 21 08:05PM -0700 >But it's a pretty high-intensity one. Don't know what makes it so, but I >classify anything with a yellow square visible in the center as >"high-intensity". Maybe not technically accurate, but there you are.   That's probably a downconversion phosphor. White LEDs are really blue LEDs with a blob of epoxy on top, loaded with yag powder that converts some of the blue to yellow.     --   John Larkin Highland Technology, Inc   lunatic fringe electronics

Jeff Liebermann <jeffl@cruzio.com>: Mar 21 08:51PM -0700 >circuitry (constant current): the voltage across the LED is constant 4v. I >presume it's a failure mode of the LED. It happens immediately upon >power-on.   I beg to differ with your diagnosis. Unless the LED has magically turned into a thermostat controlled flasher, it's not going to do that. More likely, the LED driver circuit is doing the flashing. Based on zero detail about the actual flashlight, my wild guess(tm) would be the big electrolytic that usually goes across the battery. Broken or badly soldered connections on the driver PCB are also likely.     >But it's a pretty high-intensity one. Don't know what makes it so, but I >classify anything with a yellow square visible in the center as >"high-intensity". Maybe not technically accurate, but there you are.   If it's not too much trouble, could you disclose the maker and model number of your flashlight? Extra credit for providing a link to the manufactures web site or China source link. If there are no numbers or sources, perhaps a photo of the assembled flashlight?   >What I've found so far is either a standard 5mm LED but not very bright, or >SMD types requiring heat sinks.   Yep. You're looking at the wrong stuff. Maybe something by Cree: <http://www.cree.com/LED-Components-and-Modules/Products> Nope. Ok, I give up. What the photo looks like is a common dome shaped LED (as in the Cree URL above) with a lens over it. I did some Googling looking for the lens and couldn't find it.   >It's a great little light, and I've not found anything as small, >long-lasting, with single AA that I like as much. And this is a learning >experience, so there's that.   I have one that meets your requirements. L3 Illumination L10: <http://www.candlepowerforums.com/vb/showthread.php?376058-L3-Illumination-L10-%28XP-G2-R5-or-Nichia-219-1xAA%29-Review-RUNTIMES-BEAMS-VIDEO> Single cell, very bright, tolerably priced, small, adjustable brightness, etc. However, there's a catch. It has 4 brightness levels set by twisting the two sections of the body. No problem except that it makes it a two handed operation. I would have preferred a push button at the back end. I've also measured the brightness (using my highly creative and non-standard procedure) at about 90-110 lumens (varies with temperature).   >Any pointers to a suitable replacement LED would be appreciated.   Again, I don't think it's the LED. The driver board is a more likely culprit. Put it under a magnifier and see if you can find the broken trace. Put a light behind the PCB to make it easier to see the break. If desperate, trace out the schematic and try to identify the LED controller chip. If it uses an MLCC capacitor, use a hot air gun to reflow, not a soldering iron tip.   You might also get some help in CandlePowerForums: <http://www.candlepowerforums.com>   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

Phil Allison <pallison49@gmail.com>: Mar 21 10:35PM -0700 Jeff Liebermann wrote:   > I beg to differ with your diagnosis. Unless the LED has magically > turned into a thermostat controlled flasher, it's not going to do > that.   ** The OP is probably correct and I have seen the same symptoms with 3mm red LEDs. Over time, excess DC current damages the LED chips and they intermittently drop light output and blink on and off.   Caused havoc in a Mesa Boogie amplifier when most of the dropping resistors for the 20 odd LED/CdS cell opto-couplers were the wrong value, by a factor of 10, resulting in almost 100mA of drive current.     .... Phil

DaveC <not@home.cow>: Mar 21 10:56PM -0700 > would be the big electrolytic that usually goes across the battery. > Broken or badly soldered connections on the driver PCB are also > likely.   Nebo NU15J:   https://www.nebotools.com/prod_details.php?id=31&cid=16&subid=94&subsubcid=   I like this model for its good trade-off between brightness and battery life. Might be "better", but this fits my needs. (And it ft fits in my pocket along with my micro Swiss army knife...)   No controller chip. Looks like a boost converter (inductor, BJT, schottky diode, ceramic cap).   I scoped the voltage across the LED: it's constant 4v (with a very small--20mv?--rise and fall as it switches on and off). Haven't yet measured current. Surely if there was a bad solder joint or other failure it would show up here.   Thanks for the referrals of other lights, but I'm not buying a replacement. I'm doing this for fun and to learn.   Cheers.

captainvideo462009@gmail.com: Mar 21 02:59PM -0700 I have this old Western Electric Comkey 416 (circa 1976) analog key telephone system in my house. With two primary sets and the remainder being slaves the system can handle 4 lines and 16 extensions. The sets all connect onto 66 blocks with 25 pair cable. Yes it's antiquated but it does music on hold and intercom and serves our needs.   Lately I have noticed something peculiar. If I'm speaking with another party and I put them on hold the system will stay on hold indefinitely. However if I put them on hold and they eventually hang up my system will eventually go back on hook by itself. How can it do this? As far as I know this is just a "dumb system. How could it know that the other party hung up and then to release the line. I seriously doubt that they had the technology to do this in 1975. Maybe someone (like an Ex telephone guy) might know if Western Electric could have built anything that sophisticated into this system in 1975 to detect anything like a kiss off, (I'm guessing) from the CO. Thanks, Lenny

jurb6006@gmail.com: Mar 21 03:59PM -0700 Technology was quite a bit more advanced in the 1970s than most people realize.   I'm guessing it detects the DC level on the line. Not much other way it could work eh ?   No matter what kind of phone it is, it works by modulating DC, so therefore it must present a constant load, kinda like a class A amplifier.   When I was playing around with phones I found like 45 volts DC when hung up and usually 6 or 7 when talking. Even if the phone co regulates that voltage it can't be a high current source. When the other party hangs up, even if the voltage settles to the same level there is going to be quite a positive going transient on the line. It probably detects that.   Honestly I am no expert, just fooled around with it a bit in younger days. But really I can see no other way it could do that than to detect that transient.

Jon Elson <elson@pico-systems.com>: Mar 21 08:05PM -0500 > might know if Western Electric could have built anything that > sophisticated into this system in 1975 to detect anything like a kiss off, > (I'm guessing) from the CO. Thanks, Lenny There is a disconnect signal that is (at least in the US) a 750 ms reversal of the talk battery. If you've ever held on when the other party got disconnected and there was a loud thump-thump and then you got dial tone back, that was the disconnect signal. Apparently, your KSU detects that signal.   Jon

jurb6006@gmail.com: Mar 21 10:18PM -0700 In movies etc. I have seen where when the other party hangs up you automatically get a new dial tone. Not so here, it just sits there.   But if it does do that, then it is a simple matter to detect the dial tone.

DecadentLinuxUserNumeroUno <DLU1@DecadentLinuxUser.org>: Mar 21 11:42PM -0400 >> I suggest that this is yet another posting intended to generate >> traffic and waste everyones time, for reasons unknown.   >Isn't every post here for the purpose of wasting time?   My Fluke Meter fix post wasn't.   And it works 100%. Batteries still full after 3 weeks, when it used to deplete a full 6 pack in less than 3 days.

jurb6006@gmail.com: Mar 21 04:13PM -0700 So let me get this straight. The consensus now is that it has nothing to do with the thickness of the belt but is to avoid resonance, Logically resulting in less wow and flutter I would assume.   Interesting. I remember the old Walkmans that had two flywheels going in opposite directions, not for autoreverse, but so that when the unit was moved, turned whatever, it would maintain the speed. But in that case of course the two flywheels were the same weight and diameter so the angular forces would cancel out.   Really, on the surface is seemed that the thickness of the belt was the reason for this but that has been eliminated. Would be nice to look at a few other models and see how they are put together. Ha, there is only one autoreverse deck on the property and it doesn't belong to me. That'll learn me to throw shit out.

Phil Allison <pallison49@gmail.com>: Mar 21 08:32PM -0700 > So let me get this straight. The consensus now is that it has nothing > to do with the thickness of the belt but is to avoid resonance, > Logically resulting in less wow and flutter I would assume.   ** The OP also posted his Q on sci.electronics.design and in my first reply there I pointed out the possible resonance issue as the reason for differing flywheel diameters.   A rubber belt and flywheel system has a resonant frequency - resulting from the springiness of the belt and the inertia of the wheel. I figured that where two flywheels are coupled by the same belt, it is better if their inertias are non identical so the resonant frequencies differ and so do not reinforce.       > Really, on the surface is seemed that the thickness of the belt was > the reason for this but that has been eliminated.   ** A really dopey idea based on a fallacy.   .... Phil

jurb6006@gmail.com: Mar 21 04:04PM -0700 >"Just an FYI: Flukes generally carry a lifetime warranty -"   Really. Does that apply to the 8000 series ? Buddy of mine has one the batteries leaked all over and now it acts erratic. We have NOT modified the unit, just took out the batteries. If that is under warranty hell, we'll send it in !

"pfjw@aol.com" <pfjw@aol.com>: Mar 21 05:00PM -0700 Eveready or Duracell, either will replace the unit at no cost. Chinese crap, no. Fluke would call that negligence, and rightly so.   Peter Wieck Melrose Park, PA

"Ian Field" <gangprobing.alien@ntlworld.com>: Mar 21 07:00PM <stratus46@yahoo.com> wrote in message news:5392a777-ddde-4248-99bd-496a9a09fa2e@googlegroups.com... > active drying in the dishwasher but we also have a commercial food > dehydrator for 'baking' tapes. 17 hours at 125F makes the boards look and > work like new again.   Boards have had water soluble flux since they banned the solvents to protect the ozone layer.   AFAIK: all PCBs are cleaned in water nowadays.

captainvideo462009@gmail.com: Mar 21 02:34PM -0700 > Don't be afraid to take heroic measures if the alternative is landfill.   > Peter Wieck > Melrose Park, PA? I have alot of music on reel to reel. some of the oxide comes off of some of these. I know that their days are numbered. Can I save them? thanks Lenny   What' the deal on baking tapess

MJC <gravity@mjcoon.plus.com>: Mar 21 11:01PM In article <5392a777-ddde-4248-99bd-496a9a09fa2e@googlegroups.com>, stratus46@yahoo.com says... > commercial food dehydrator for 'baking' tapes. 17 hours at 125F makes > the boards look and work like new again.   > G²   Reminds me of the "best butter" used by the March Hare in his watch, as told by Lewis Carroll!   Mike.

amdx <nojunk@knology.net>: Mar 21 05:16PM -0500 On 3/19/2016 3:14 PM, Bob F wrote: >> that heater and have some smart investigator tie it to my replacing >> the thermal fuse with a piece of wire.   > I bought a bunch from Newegg for cheap.   I bought a bunch also, I now have use for one. If only I can remember where I put them.     I have a circuit that I built a few years ago, 12V 500ma wallwart, driving a 7809 regulator. Recently the circuit quit working, I measured the voltage to the 9v regulator. I was 0.328 volts, I didn't figure it was a shorted load, because the wallwart was not warm. It turns out the primary of the wallwart is open, most likely the thermal fuse. It was a little odd to get the 0.328V while connected to the load, but I guess the 7809 draws very little current at low voltage. I installed another wallwart and all is fine. Mikek

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