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harry newton <harry@is.invalid>: Dec 27 03:28PM Talk about drastic!   Apple throttled your iPhone by cutting its speed almost in HALF!   "After replacing the battery, Geekbench showed that the scores had nearly doubled."   <http://nymag.com/selectall/2017/12/is-apple-slowing-down-iphones-with-aging-batteries.html>

"David Farber" <farberbear.unspam@aol.com>: Dec 26 02:16PM -0800 I'm servicing a Behringer EUROPOWER PMH2000. The + and - 15 volt regulators need replacing because the leads have failed. The transistor is mounted to the chassis at a 90 degree angle and then soldered to the pc board. The problem is that pc board fits very tightly into the chassis. The leads on the regulators keep getting flexed with each pc board removal. Anyway, I want to replace them because a couple of the leads have broken off. They are packaged in a TO-220 case. The center tab is nonmetallic so it is insulated from the chassis. Though the schematic says terminal 2 is grounded in the 7815A anyway, I was wondering if it made any difference whether or not I purchased ones with metallic backing or ones with a plastic backing.   I just looked at the LM7915 spec sheet and it says that terminal 1 is ground and terminal 2 is the input which is reversed from the positive regulator. It also doesn't mention whether or not it has a metal tab, which if it did, would have to be insulated from the chassis. Do any of you have any experience replacing these regulators in a chassis mount situation?   Thanks for your reply. -- David Farber Los Osos, CA

whit3rd <whit3rd@gmail.com>: Dec 26 04:56PM -0800 On Tuesday, December 26, 2017 at 2:16:52 PM UTC-8, David Farber wrote: > want to replace them because a couple of the leads have broken off. They are > packaged in a TO-220 case. The center tab is nonmetallic so it is insulated > from the chassis.   I presume, however, that the tab connects to the chassis for heatsinking?   Best practice if the strain on the component is breaking wires, is to use a strain-relieved wiring connection, like a few-inches pigtail wiring from the regulator to a female Molex KK socket; this will plug onto male pins mounted in the printed wiring board, 0.100" centers spacing just like the LM78xx.   Those regulators are available in fullpak (epoxy insulated tab), metal-tab-wth-hole, and short-metal-tab (for soldering to a surface mount "heatsink").

Phil Allison <pallison49@gmail.com>: Dec 26 11:42PM -0800 David Farber wrote:   ---------------------- > want to replace them because a couple of the leads have broken off. They are > packaged in a TO-220 case. The center tab is nonmetallic so it is insulated > from the chassis.   ** The *mounting tab* is definitely metal, just coated in epoxy to insulate it.     > It also doesn't mention whether or not it has a metal tab, which if it did, > would have to be insulated from the chassis. Do any of you have any > experience replacing these regulators in a chassis mount situation?   ** If the originals are held on with a clamp, you need to buy the same again.   If held with 3mm bolts, you can use the ones you have.   BUT you MUST add insulating bushes and mica pads to BOTH - plus a smear of white thermal grease.   Bolting the positive one straight to the chassis is likely to result in ground loop hum.     ... Phil

Jeff Liebermann <jeffl@cruzio.com>: Dec 26 09:04AM -0800 >Thanks for the help. This is an outdoor display, but I use it indoors.   To the best of my limited knowledge, indoor and outdoor Hannukah lights are the same.   Incidentally, look for the UL 588 label: <https://industries.ul.com/wire-and-cable/seasonal-lighting>   >So no animals have chewed on the wires.   Assumption, the mother of all screwups. Just inspect the wiring and see if there's any damage. You got used which means it could have been abused in a multitude of ways.   >I dont hasve whole sections out, >just two or three bulbs that dont light.   It could be a parallel wired affair with built in current limiting resistors as mentioned in the patent: <https://www.google.com/patents/US8007129>   >I could just leave it alone, >but if it's series wired, I know it will eventually overload other >bulbs.   Look at the way series arrays are wired. There's no way to overload them, unless you're into shorting out the LED's that died.   >(Yea, I need to get a better look at the way it's wired).   You need to get a better look at the way it's wired. You need to get a better look at the way it's wired. You need to get a better look at the way it's wired. You need to get a better look at the way it's wired. I thought it would help if I repeated that a few extra times.   >Plus >this was a very costly and very pretty display, so I want to keep it in >tip-top shape. (Which is why I only use it indoors).   Costly or overpriced?   >The reason I got this, was because it was a store display, and I got it >at a much reduced price.   Yes, but you're suppose to do that AFTER the holidays, when the stores unload all their holiday paraphernalia. Are you sure you got a good price, or did the store just unload something broken which they couldn't sell?   >So, running it in the store for weeks probably >killed the weak LEDs.   Unless overheated or run a unusually high current, LED's should last thousands of hours. You're thinking of the bad old days of incandescent lights, where replacing bulbs was a regular exercise.   Before you replace any LED's, You need to get a better look at the way it's wired and determine if there's an internal ohmsistor or current limiter. Replacing one of those with an ordinary LED is going to produce a very bright flash before the fuse blows.   >However there was no box or instructions.   If anything were included in the box, it would be a wholesale repudiation of responsibility and various legal disclaimers in a dozen foreign languages.   I originally suspected that if I did the research, I would find that there are a few giant factories in China making both the quality and the junk lights, which are then packaged, private labeled, distributed, and sold by a multitude of disreputable vendors. Well, more than a multitude. This list shows 863 manufacturers: <http://www.made-in-china.com/products-search/hot-china-products/Tree_Light.html> and 535,000 vendors in China: <https://www.alibaba.com/countrysearch/CN/christmas-light.html> Identifying your lights may be difficult.   >I'm sure >it was NOT made in the US, so finding the manufacturer is not gonna help >determine the proper bulbs.   There are no Hanukah light manufacturers left in the USA. <https://www.christmasdesigners.com/blog/made-in-usa-christmas-lights/>   -- 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

tabbypurr@gmail.com: Dec 26 09:46AM -0800 On Tuesday, 26 December 2017 17:04:57 UTC, Jeff Liebermann wrote: > On Tue, 26 Dec 2017 05:08:41 -0600, oldschool@tubes.com wrote: 8<   > >So, running it in the store for weeks probably > >killed the weak LEDs.   unlikely   > and determine if there's an internal ohmsistor or current limiter. > Replacing one of those with an ordinary LED is going to produce a very > bright flash before the fuse blows.   Quicker to just replace & see if they work. If the new LEDs light and the old don't, then different limited LEDs needed.     NT

Jeff Liebermann <jeffl@cruzio.com>: Dec 26 11:01AM -0800 >Quicker to just replace & see if they work. If the new LEDs >light and the old don't, then different limited LEDs needed. >NT   I was wondering what the white stuff that falls out of the sky around this time of year might be. Initially, I thought it might be snow, but after considering your suggestion, I suspect it might be the fallout from exploding white LED's that were tested using your methodology.     -- 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

tabbypurr@gmail.com: Dec 26 01:59PM -0800 On Tuesday, 26 December 2017 19:01:41 UTC, Jeff Liebermann wrote: > but after considering your suggestion, I suspect it might be the > fallout from exploding white LED's that were tested using your > methodology.   Lol. I doubt it. The OP hasn't a clue what he's got, the possibility of killing a 1 cent LED by overcurrent is no big deal.     NT

bitrex <bitrex@de.lete.earthlink.net>: Dec 26 09:18PM -0500 On 12/26/2017 08:16 AM, Fox's Mercantile wrote: >> is not gonna help determine the proper bulbs.   > Ya know, for someone who is constantly pissing and moaning about > "Unreliable Chinese shit" you sure seem to buy a lot of it.   Like politicians who want to ban porn because they've "done the research" on how awful it all is. Ah, ok, definitely tell me all about it then Mr. Expert

oldschool@tubes.com: Dec 26 06:44PM -0600 On Fri, 22 Dec 2017 18:04:44 -0500, "Percival P. Cassidy" >never totally extinguish but only dim to a a faint glow.   >Any way of using both the illuminated switch and the 40W LEDs?   >Perce   Are you using dimmable or non-dimmable LED bulbs?   That may make a difference.... (just a thought).

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oldschool@tubes.com: Dec 25 02:34PM -0600 I have one of those costly animated outdoor Christmas displays with white LED lights on it. A few of the LEDs are dead. There is no manufacturer info available.   I know LEDs all have a different current draw. I am not sure how critical it is, to choose a replacement bulb. Does it matter, or will any white LED work, as long as it fits the socket?   These are sort of the domed type, but have flat tops. Nothing fancy, and they dont have to look identical since they are inside of a coating.   My thought is to just buy a string of white xmas lights after the holiday (on sale) and use them for replacement bulbs. But maybe I need to know more about the current draw or something. I ve never had to replace LED bulbs before. I replaced amny of the old xmas light strings that has incandescent bulbs, and with them, you had to match the number of bulbs to get the correct voltage.

Jeff Liebermann <jeffl@cruzio.com>: Dec 25 02:18PM -0800 >ve never had to replace LED bulbs before. I replaced amny of the old >xmas light strings that has incandescent bulbs, and with them, you had >to match the number of bulbs to get the correct voltage.   Two days after I hung my string of Hanukah lights, the local squirrels gave it a taste test resulting in about half the string going dark. You might inspect your lights for similar damage. If so, splice or solder the wires back together and it should work. Be sure to use shrink tube or liquid electrical tape for insulation. My 25ft string has about 6 breaks from similar squirrel damage from previous years.   If you plan to fix it, take the time to determine how it's wired. Some possible schematics and wiring diagrams: <https://www.google.com/search?q=led+christmas+light+wiring&tbm=isch> Trace out your wiring and see what matches.   Try to fix just one section that's currently not lit. If you find it, don't fix it immediately. Use a VOM or DVM to measure the current and you have your answer. Some LED's have built in resistors or current regulators like this: <https://www.google.com/patents/US8007129>   You can determine which LED is blown in one segment, attach needles to the VOM or DVM leads and probe across each LED by puncturing its wires. If you see an unusually large voltage, the LED that you're straddling is the culprit. Be careful as most light strings do not have any isolation from the AC power line. Use a 117-117VAC isolation transformer or be VERY careful when probing live power.       -- 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

whit3rd <whit3rd@gmail.com>: Dec 25 05:42PM -0800 > I know LEDs all have a different current draw. I am not sure how > critical it is, to choose a replacement bulb. Does it matter, or will > any white LED work, as long as it fits the socket?   There's multiple shades of 'white' available; if you can't see the replacements side-by-side, they won't be exact.   Generally available (new stock) LEDs in the same package are likely (for heatsinking reasons) to be electrically compatible. And, cheaper than a set, you can get bags of LEDs from a variety of suppliers, like this: <https://www.ebay.com/itm/3mm-white-LED-light-100pcs-Light-Emitting-Diode/182490012569?epid=571206918>   but polarity, case size, color, are just as mysterious as the 'no manufacturer info available' item you are thinking to rebuild.

oldschool@tubes.com: Dec 26 05:08AM -0600 On Mon, 25 Dec 2017 14:18:44 -0800, Jeff Liebermann <jeffl@cruzio.com> wrote:   >straddling is the culprit. Be careful as most light strings do not >have any isolation from the AC power line. Use a 117-117VAC isolation >transformer or be VERY careful when probing live power.   Thanks for the help. This is an outdoor display, but I use it indoors. So no animals have chewed on the wires. I dont hasve whole sections out, just two or three bulbs that dont light. I could just leave it alone, but if it's series wired, I know it will eventually overload other bulbs. (Yea, I need to get a better look at the way it's wired). Plus this was a very costly and very pretty display, so I want to keep it in tip-top shape. (Which is why I only use it indoors).   The reason I got this, was because it was a store display, and I got it at a much reduced price. So, running it in the store for weeks probably killed the weak LEDs. However there was no box or instructions. I'm sure it was NOT made in the US, so finding the manufacturer is not gonna help determine the proper bulbs.

Fox's Mercantile <jdangus@att.net>: Dec 26 07:16AM -0600 > I'm sure it was NOT made in the US, so finding the manufacturer > is not gonna help determine the proper bulbs.   Ya know, for someone who is constantly pissing and moaning about "Unreliable Chinese shit" you sure seem to buy a lot of it.       -- "I am a river to my people." Jeff-1.0 WA6FWi http:foxsmercantile.com

tabbypurr@gmail.com: Dec 26 06:12AM -0800 > killed the weak LEDs. However there was no box or instructions. I'm sure > it was NOT made in the US, so finding the manufacturer is not gonna help > determine the proper bulbs.   If they're 5mm LEDs, a bag of mixed random 5mm chinese LEDs would work. Who knows if they'll match on brightness & colour though.     NT

Tim R <timothy42b@aol.com>: Dec 26 05:52AM -0800 I've had that happen on a CRT not quite that old.   It's really annoying. There was always some combination of inputs from the remote that fixed it, but sometimes it took us a couple weeks to hit on it again.

"~misfit~" <shaun.at.pukekohe@gmail.com>: Dec 26 02:09PM +1300 > and some pots, switches, jacks and you have a complete device. They > are made for amps, pre-amps, test equipment and lots of other stuff. > So I wonder if they are made for pass filters????   https://www.aliexpress.com/item/Low-Pass-Filter-Plate-Subwoofer-Preamp-Board-2-1-3-Channel-DC-10-24V-22Hz-300Hz/32590327578.html   I've used one of these and it seems to work fine. For $5 delivered it's hard to not try it. -- Shaun.   "Humans will have advanced a long, long way when religious belief has a cozy little classification in the DSM*." David Melville (in r.a.s.f1) (*Diagnostic and Statistical Manual of Mental Disorders)

tabbypurr@gmail.com: Dec 25 07:14PM -0800 On Tuesday, 26 December 2017 01:09:43 UTC, ~misfit~ wrote: > > On Fri, 8 Dec 2017 07:52:47 -0000 (UTC), gregz <zekor@comcast.net> > > wrote: > >> <oldschool@tubes.com> wrote: 8<     > https://www.aliexpress.com/item/Low-Pass-Filter-Plate-Subwoofer-Preamp-Board-2-1-3-Channel-DC-10-24V-22Hz-300Hz/32590327578.html   > I've used one of these and it seems to work fine. For $5 delivered it's hard > to not try it.   What's the point of it? A couple of RCs does the job without waiting for delivery or paying a thing. Or using a psu, or adding noise to your signal.     NT

"~misfit~" <shaun.at.pukekohe@gmail.com>: Dec 26 12:43PM +1300 > increasing failure rate starting at around age 10.   > Peter Wieck > Melrose Park, PA   Thanks Peter, that's what I though made the most sense (though there was a full stop between 'caps' and 'Frakus' which made me wonder) but even googling 'Frakus capacitor' didn't confirm my suspicions.   Cheers, -- Shaun.   "Humans will have advanced a long, long way when religious belief has a cozy little classification in the DSM*." David Melville (in r.a.s.f1) (*Diagnostic and Statistical Manual of Mental Disorders)

Jeff Liebermann <jeffl@cruzio.com>: Dec 25 06:31PM -0800 On Sun, 24 Dec 2017 04:53:09 -0800 (PST), "pfjw@aol.com"   >Frakus being a German brand of electrolytic capacitor with a rapidly increasing failure rate starting at around age 10.   I Googled for "Frakus capacitors" and found nothing. Google refered me to Frako capacitors at: <http://www.frako.com/en/products/power-capacitors/> which is a German company but which makes big power factor correction capacitors for industrial applications that are unlikely to be found inside a Bose Wave CD player. Are you sure about the "Frakus" name?     -- 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

"Ian Field" <gangprobing.alien1@virginmedia.com>: Dec 25 05:27PM "~misfit~" <shaun.at.pukekohe@gmail.com> wrote in message news:p1o1uc$5km$2@dont-email.me...   > I'm always a bit shy about soldering onto a cell - worried I'll cook it. > That's why I left the nickel strip on in the first place, so it'd be there > if I needed to solder the cell somewhere.   The bus strip is a little more thermal resistance on the way to the cell.   A strong active flux helps make the joint quickly so damage is minimised.

"~misfit~" <shaun.at.pukekohe@gmail.com>: Dec 26 12:45PM +1300 Once upon a time on usenet Ian Field wrote: > cell. > A strong active flux helps make the joint quickly so damage is > minimised.   Cheers, -- Shaun.   "Humans will have advanced a long, long way when religious belief has a cozy little classification in the DSM*." David Melville (in r.a.s.f1) (*Diagnostic and Statistical Manual of Mental Disorders)

JBI <JBI@ez1.net>: Dec 25 01:08PM -0500 >> I'm taking this new heater back, I can't stand the burning plastic smell >> it's producing.   > Buying a more expensive heater from a less-cheap store might be a good idea, too.   The quartz heater I linked to earlier seems to be doing a surprisingly good job. It seems to heat up the room more quickly than the Honeywell did, no smell from the start and not running continuously. The only inconvenience I can find is that the analog thermostat, like the Honeywell, isn't very accurate. If I try presetting it when the timer triggers the heater early morning, it's still plenty cold in the room when I walk in several hours later. Due to that, I just might use the external thermostat (I ordered it before recognizing the possible hazards mentioned prior and it arrived on Saturday) I also mentioned before, but leave the heater thermostat at a point where it won't ever run continuously. I think it would be more accurate than the heater's since it's digital.

Fox's Mercantile <jdangus@att.net>: Dec 25 01:03PM -0600 On 12/25/17 12:08 PM, JBI wrote: > I think it would be more accurate than the heater's since it's digital.   Being digital does not equal accuracy.   -- "I am a river to my people." Jeff-1.0 WA6FWi http:foxsmercantile.com

tabbypurr@gmail.com: Dec 25 12:11PM -0800 On Monday, 25 December 2017 19:03:38 UTC, Fox's Mercantile wrote: > On 12/25/17 12:08 PM, JBI wrote: > > I think it would be more accurate than the heater's since it's digital.   > Being digital does not equal accuracy.   no not at all. Portable heaters with bimetal stats tend to lack compensation, without which the stat is almost useless.     NT

bruce2bowser@gmail.com: Dec 25 09:57AM -0800 On Sunday, December 24, 2017 at 5:56:45 AM UTC-5, frank wrote:   > > yellow is used in lieu of gold for tolerance - it's non-metallic.   > the resistors I'm talking about have both gold (as 4th band) and yellow > as 5th band.   Too bad there is usually so little difference between yellow and gold as opposed to blue and gold or silver and gold.

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