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Cydrome Leader <presence@MUNGEpanix.com>: Mar 22 03:58PM > 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   The last duracell battery leakage claim I filed resulted in getting a prepaid credit card. Had to get an all new flashlight, but it worked out in the end. Not sure how they deal with more expensive stuff like test equipment.

DaveC <not@home.cow>: Mar 21 11:56PM -0700 > 2108A > 2216/36   > Thanks.     Well, "BJT" may be a misnomer. Don't know what it is...

Tilmann Reh <usenet2007nospam@autometer.de>: Mar 22 09:45AM +0100 DaveC schrieb: >> 2216/36   >> Thanks.   > Well, "BJT" may be a misnomer. Don't know what it is...   Probably.   Maybe it's a MicrOne ME2108A - a switching regulator. PDFs may be available only with chinese (or the like) text...   Tilmann   P.S. Google for SOT89 2108A to get some results...

DaveC <not@home.cow>: Mar 22 08:52AM -0700 > PDFs may be available only with chinese (or the like) text...   > Tilmann   > P.S. Google for SOT89 2108A to get some results...   Thanks Tilmann. Found a useful datasheet:   http://img.ozdisan.com/ETicaret_Dosya/431770_1622138.pdf   The example for the 2108A in the datasheet duplicates the one in my circuit.   Cheers.

Syd Rumpo <usenet@nononono.co.uk>: Mar 22 09:10AM On 22/03/2016 03:51, Jeff Liebermann wrote:   <snip>   > 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.   Thermostat controlled flasher is probably the exact description. It happens when LEDs are driven straight from batteries too, and is probably the bond wire heating and cooling making intermittent contact at a few Hz.   I have a cheap LED torch which uses nine parallel connected white LEDs running directly from 3 AAs. After a battery replacement, one is out, four flash at different rates, and four are on.     Cheers -- Syd

Phil Allison <pallison49@gmail.com>: Mar 22 04:01AM -0700 Syd Rumpo wrote:     > I have a cheap LED torch which uses nine parallel connected white LEDs > running directly from 3 AAs. After a battery replacement, one is out, > four flash at different rates, and four are on.   ** Ahhh - so you have seen it really happen too !!!   Bit like sighting the Loch Ness Monster.   Bonding certainly seems to be involved and LEDs are very sensitive to high temps - way more than silicon semiconductors.   Gallium arsenide is even whimpier than Germanium, lifespan deteriorating quickly above room temp.     .... Phil

N_Cook <diverse@tcp.co.uk>: Mar 22 03:42PM On 22/03/2016 05:56, DaveC wrote:   > Thanks for the referrals of other lights, but I'm not buying a replacement. > I'm doing this for fun and to learn.   > Cheers.   Desolder the original LED, carefully , as balance of probability it will be fine. Jumper in any old high power LED and see if that flashes too.

N_Cook <diverse@tcp.co.uk>: Mar 22 02:01PM About 3 hours to render down one sheet to all these bands, not all sliced down as can do to required thickness when required. Went out and bought another sheet , as a seasonal product, and the idea worked so well. http://diverse.4mg.com/silicone_bands_easter.jpg The blow hole plug plus cylinders shown , with one stretched over a pinch wheel. As long as the increased diameter does not rub on the carrier, AFAIR always enough clearance. So those plus standard O Orings , one or 3 layed in periphery for pulley tyres(flat edges are not required for tyres in tape decks), completes the universal rubber tool kit. Plus remnants in pic. minimum I've "bean sliced" down to without breaking is about 0.3mm thick.

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