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itt788 <itt788@outlook.com>: Jul 19 05:40PM I have a laptop motherboard which suddenly had its DC input ends short circuited. It workded normally for hours and switched off normally. When trying to run it again some day after it won't boot up and I noticed that the DC input ends were short circuited.

Jeff Liebermann <jeffl@cruzio.com>: Jul 19 10:47AM -0700 >circuited. It workded normally for hours and switched off normally. When >trying to run it again some day after it won't boot up and I noticed that >the DC input ends were short circuited.   Look for a big reverse power protection diode across the DC input connector. Also, if your battery charger is of the "universal" variety, look for the power being applied backwards.   If that's not it, I suggest you disclose the maker and model number, and if it works on battery 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

M Philbrook <jamie_ka1lpa@charter.net>: Jul 19 06:35PM -0400 In article <55abe0f8$0$3017$426a74cc@news.free.fr>, itt788@outlook.com says... > circuited. It workded normally for hours and switched off normally. When > trying to run it again some day after it won't boot up and I noticed that > the DC input ends were short circuited.   Plugged the wrong adapter into it?   Do you have others in the place that also likes to plug things into stuff like that?   It just sounds to sneaky..   Jamie

itt788 <itt788@outlook.com>: Jul 20 04:26PM Le Sun, 19 Jul 2015 17:40:08 +0000, itt788 a écrit :   > circuited. It workded normally for hours and switched off normally. When > trying to run it again some day after it won't boot up and I noticed > that the DC input ends were short circuited.   I wrote a bit too fast my message and I skipped some important information.   When I tried to boot up the computer and noticed it won't do I first checked the transformer and it showed the right voltage on the voltmeter screen. I also tried to draw some power using a fixed resistor which value was chosen to get something around 1 A and indeed the expected current values flowed within the resistor.   Then when trying to plug back it into the computer I noticed a big spark everytime I was trying to plug it in. That's when I noticed with an ohmmeter that the DC input ends were short-circuited. I also tested the battery, the voltmeter show a nice 0 Volt for each cell while it should fully charged.   I disassembled the computer and noticed that the short-circuit was caused by a MOSFET next to the DC input socket on the motherboard but after I replaced it, this new component also got killed and shorted the DC input ends.

N_Cook <diverse@tcp.co.uk>: Jul 20 10:07AM +0100 Model number HD604 is the only label, and no identifier inside. I'm modifying the lens mount to be able to focus it to less than the made 12 foot minimum proj-screen distance. It has S-vid, SVGA, 2x HDMI inputs and a USB socket. Would anyone know if the USB can be used from a PC as a video feed also (OSD of sources is ambiguous) and if so, would the pc-driver have to be specific to this unknown make/model of projector or some generic driver.

Mike Tomlinson <mike@jasper.org.uk>: Jul 20 12:27PM +0100 En el artículo <moidmh$kou$1@dont-email.me>, N_Cook <diverse@tcp.co.uk> escribió:   >Would anyone know if the USB can be used from a >PC as a video feed also   I would have thought that very unlikely, it's more likely to allow a memory stick or external hard disc to be connected to view photos or to play .mp3 music/.mp4 videos.   -- (\_/) (='.'=) (")_(")

N_Cook <diverse@tcp.co.uk>: Jul 20 12:52PM +0100 On 20/07/2015 12:27, Mike Tomlinson wrote:   > I would have thought that very unlikely, it's more likely to allow a > memory stick or external hard disc to be connected to view photos or to > play .mp3 music/.mp4 videos.   That sounds likely, so acting like a digital picture frame. The projector exterior looks like this http://www.led-projectors.co.uk/shop/used-led-504/ HD 504, HD probably meaning the weasel phrase HD compatible for this one also. They've used a first generation, discharge lamp type injection moulder for the casing as there is the protruding section for the removable cover for the discharge lamp of Epson? earlier projectors, now irrelevantly protruding below the casing and moulded as one piece now. Otherwise like the OHP converter to video , large 4x6 inch or so LCD and large optics to allow for distributed LED lamp source. I like the,KISS, keystone adjuster, simply pivots a mirror directly by turning the knob on the case side

N_Cook <diverse@tcp.co.uk>: Jul 20 05:13PM +0100 Looks as though OSD source select labelled DTV/Card is the USB source so presumably USB digital TV or card=thumbstick? Anyway got the minimum focus adjustment range down from 3.1m to 1.3m , retaining whatever the maximum was.

mroberds@att.net: Jul 19 10:15PM > I hooked up the inverter directly to the car battery in the car.   What did the wiring from the inverter to the car battery look like? If it involved either a cigarette lighter plug or alligator clips, improving that connection will help a little. Ideally you would have fairly thick cables (8 AWG or thicker), as short as possible, running from the inverter to the battery terminals. Remember, if the inverter is putting out the full 500 W, it will be drawing around 42 amps from the battery.   > If the car wasn't running the entire time, the items connected to the > inverter would start flickering on and off after a period of time.   This was probably the low-voltage shutdown in the inverter trying to operate. Most of them will shut off the AC output when the DC input voltage gets too low, so as to avoid running the battery down too far. Usually this isn't adjustable, but on some inverters it might be... check the manual if you have one.   > There certainly wasn't a lot of wattage being drawn.... the TV uses > like 100 watts   Have you measured it or looked at the nameplate? This is from 2009 http://www.enerank.com/tv-power-consumption-energy-efficiency-46-inches.php but 46" TVs drew from 107-310 W.   > with the lights maybe 10 watts each, and there were 2.   A 60 W equivalent CFL is usually 13 or 14 W. If you're playing games like this, a Kill-a-Watt or similar portable watt-hour meter is a good tool. http://www.p3international.com/products/p4400.html   Standard disclaimers apply: I don't get money or other consideration from any companies mentioned.   Matt Roberds

avagadro7@gmail.com: Jul 19 04:05PM -0700 the OEM alternator, cost effective, works only on the highway where rpm produces power. Generalizing, a Ford 120amp alternator supplies lights and air at 50-60mph. Add a stereo amp, way over limits. The negative threshold comes slowly with yellow lights after 2-3 hours of asking a very good battery for more discharge than charge.   A 200amp alternator (Summit Racing) claims production of 120amps at idle but give it 15-20 mph. The OEM needs 65mph to give 120amps.   The battery your using may not be quality or fresh. Charging takes power and voltage the system may not support but that the OEM alternator at 65mph does. The 200amp unit charges at 45 mph in abt 20 miles.   drivers 'charging' dead batteries at idle after jump starting are not getting their $$$ worth.

avagadro7@gmail.com: Jul 19 05:30PM -0700 > A 200amp alternator (Summit Racing) claims production of 120amps at idle but give it 15-20 mph. The OEM needs 65mph to give 120amps.   > The battery your using may not be quality or fresh. Charging takes power and voltage the system may not support but that the OEM alternator at 65mph does. The 200amp unit charges at 45 mph in abt 20 miles.   > drivers 'charging' dead batteries at idle after jump starting are not getting their $$$ worth.   ++++++++++++++++     Google Images offers a menu of chart information or search your alternator   https://goo.gl/vvXQXM   https://goo.gl/X9bapx   Powerstream under 'technical resource' offers a wire size calculator     http://www.powerstream.com/

avagadro7@gmail.com: Jul 19 03:55PM -0700 On Sunday, July 19, 2015 at 12:32:42 PM UTC-4, Jeff Liebermann wrote: > 150 Felker St #D http://www.LearnByDestroying.com > Santa Cruz CA 95060 http://802.11junk.com > Skype: JeffLiebermann AE6KS 831-336-2558   The ELECTRONICS CLEANER's msds lists no silicone or...but yes there is a naptha of unknown character.   CRC prob has the ground covered for soldering but jus' wondering you know.   I'm using this CRC for lubing lugnut studs when changing tires. The solder is on a relay board for aux PITA in my E250.

Jeff Liebermann <jeffl@cruzio.com>: Jul 19 05:27PM -0700 >> you're using to clean up your soldering. Then check the MSDS listing >> for any oils or additives that might consititute a residue.   >The ELECTRONICS CLEANER's msds lists no silicone or...but yes there is a naptha of unknown character.   What's the name or product number?   >CRC prob has the ground covered for soldering but jus' wondering you know.   I'm also wondering why it's so difficult to extract the name or product number from you.   >I'm using this CRC for lubing lugnut studs when changing tires. The solder is on a relay board for aux PITA in my E250.   If your unspecified product is a lubricant, then it has some kind of lubricant residue. Methinks that would be a bad idea for cleaning off the flux after soldering.   -- 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

Jeff Liebermann <jeffl@cruzio.com>: Jul 19 11:03AM -0700 On Sat, 18 Jul 2015 08:59:50 -0700, "Snuffy \"Hub Cap\" McKinney"   >> > I would not recommend the TRO480BS. Many problems -- those I recall are door can't be adjusted to close evenly, letting too much air in/out on one side. Top and bottom heaters don't heat equally - have to turn toast over to brown both sides, etc.   >> Try posting in sci.electronics.repair   >Thanks.   The B&D TR048BS has one good feature... it's cheap. Typically about $30 when on sale. According to a few reviews that I skimmed, everything else about it is marginal. If a typical parts vendor: <http://www.ereplacementparts.com/black-and-decker-tro480bs-toaster-oven-parts-c-4167_124449_182647.html> wants $11.29 for the timer knob, I can imagine what a replacement timer would cost. Methinks buying a replacement toaster oven might be cheaper. Or, as somone else suggested, try AliExpress. This looks like a possible: <http://www.aliexpress.com/item/30-minutes-pressure-cookers-microwave-oven-timer-parts-mechanical-timer-type-250V6-5A/1573000112.html>   You didn't bother to mention whether the mechanism or the contacts failed on your existing timer. If the contacts, I suggest you take it apart and clean the contacts, which might fix the problem.   Incidentally, I use a similar B&D toaster oven for reflow soldering electronics: <http://802.11junk.com/jeffl/pics/repair/BGA%20reflow/index.html>   -- 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

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