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bitrex <bitrex@de.lete.earthlink.net>: Aug 19 01:35PM -0400 > Increasing the capacitance does increase the start up surge current - but most diodes have large single cycle ratings. The 1N4004 has a 1amp average current rating with a * 30amp * single cycle rating.   > http://www.onsemi.com/pub_link/Collateral/1N4001-D.PDF   > .... Phil   A good point that I've seen Phil harping away on in the past; maybe someday folks will get the picture.   I've seen the same error stated in ~40 year old textbooks... --     ----Android NewsGroup Reader---- http://usenet.sinaapp.com/

ohger1s@gmail.com: Aug 19 11:10AM -0700 On Thursday, August 18, 2016 at 12:38:31 PM UTC-4, KenO wrote:     > I have a hard time believing that Samsung would continue to use poor quality caps in their LED TVs.   Oh please. Manufacturers will use the cheapest part they believe they can get away with, and Samsung is just as bad as anyone else. But more than that, this was most likely a bad run of caps, not just a crappy selection. If you replace this with the cheapest one you can find of the same value and voltage I promise you it will last a lot longer than your OEM cap did.   And if you really want to pick on Samsung, their LED TVs are killing LEDs in the display in wholesale numbers. The last one we did had only 11 out of 44 still working (after I jumped out the open one that caused the shutdown). 32 LEDs shorted and one open after 2 years of service. THAT is crappy design and/or part selection.   > Instead am wondering if the Samsung BN44-00554B is a poor design?   There's no "design" issue involved with your particular failure. It's a simple full wave bridge and bypass filter. If you want to say the cap was cheaply spec'd out, that's fair although I still believe it was just a shitty run of caps.   >>If this is correct then the 47uF 160 V 105 C cap should be upgraded. My problem is I have No knowledge or experience in this area, which is why am asking for suggestions.   If it makes you feel better, put in a 68uf/250v/105C and get it from Panasonic.   > Do you know if the schematic is available on line?   Not sure, but it probably isn't. Most service manuals these days give you block diagrams and parts lists but not much else. It's often easier to just get the datasheets of the ICs in the circuit and work with those than waste time looking for schematics.

John Robertson <spam@flippers.com>: Aug 19 11:27AM -0700 On 08/15/2016 8:08 PM, Phil Allison wrote:   > http://www.onsemi.com/pub_link/Collateral/1N4001-D.PDF   > ..... Phil   I understand that one can calculate inrush current easily; divide input voltage by ESR of the capacitor. So a 220ufd cap (rated at 25V or less - 0.4R ESR) run at 12V will have an inrush current of 12/0.4 = 30A... However a capacitor rated at 35V may have an ESR of 0.2R (60A) and at 63V the ESR may be down to 0.15R (80A @ 12V)   Or am I doing something wrong here...   John :-#)#   -- (Please post followups or tech inquiries to the USENET newsgroup) John's Jukes Ltd. 2343 Main St., Vancouver, BC, Canada V5T 3C9 (604)872-5757 or Fax 872-2010 (Pinballs, Jukes, Video Games) www.flippers.com "Old pinballers never die, they just flip out."

Phil Allison <pallison49@gmail.com>: Aug 19 07:16PM -0700 John Robertson wrote:   > However a capacitor rated at 35V may have an ESR of 0.2R (60A) and at > 63V the ESR may be down to 0.15R (80A @ 12V)   > Or am I doing something wrong here...   ** When you simply connect an electro to a DC source, your calc gives the peak surge value.   However, line frequency and SMPSs are way more complicated and the latter usually include a "soft" start systems for the input AC and DC output sides.         .... Phil

KenO <kenitholson@yahoo.com>: Aug 20 09:11AM -0700 ohg,   "Samsung, their LED TVs are killing LEDs in the display in wholesale numbers. The last one we did had only 11 out of 44 still working (after I jumped out the open one that caused the shutdown). 32 LEDs shorted and one open after 2 years of service. THAT is crappy design and/or part selection."   Have not checked the display LEDs yet. Could bad LEDs have caused the 47uF cap to fail?   If yes seems like necessary to protect the display LEDs.   Did see mention about turning down the display level.

"Danny D." <dannydiamico@yahoo.com>: Aug 19 11:16PM Does the difference in resistance matter if you replace a 24-inch 30mv thermocouple that has a thermal switch versus one without the thermal switch? http://i.cubeupload.com/xqThcA.jpg   I bought a generic Honeywell 30mv 24-inch thermocuple (PN CQ100A1013) from Ace Hardware: http://www.acehardware.com/product/index.jsp?productId=11877505   That picture in the URL above is wrong because it's 24 inches: https://www.amazon.com/Honeywell-CQ100A1013-Replacement-Thermocouple-Furnaces/dp/B000BPHNW2#productDetails   When I went to put it in the hot water heater, I belatedly realized the original thermocouple has an integral thermal switch. http://i.cubeupload.com/TtyF4c.jpg   I know the length matters, from a resistance standpoint, but the hardware store owner had never heard of a thermocouple with at thermal switch before: http://i.cubeupload.com/z1862F.jpg   The thermal switch is a safety feature that will shut down the pilot if the heat under the hot water heater gets too great: http://i.cubeupload.com/Qh4PMI.jpg   When I call Sears in San Jose at 408-274-2593, they confirm the part number is PN 9000056015 but that replacement part doesn't seem to have a thermal switch on it. http://www.supplyhouse.com/AO-Smith-9000056015-Thermocouple-Kit-Model-TC-K24 https://www.heritageparts.com/Napa-Technology/Manufacturers/A-O-Smith/A-O-SMITH-THERMOCOUPLE/p/AOS9000056015 http://www.jupiterheating.com/ao-smith/parts/9000056015.html http://www.terapeak.com/worth/new-state-a-o-smith-9000056015-thermocouple-kit-model-tc-k24/230984311909/   Have you ever had to make the decision of whether to replace a thermocouple that had a built-in thermal switch with a generic thermocouple that had no thermal switch? Did the resistance match? http://i.cubeupload.com/nFG8Ip.jpg

"Danny D." <dannydiamico@yahoo.com>: Aug 20 01:21AM On Fri, 19 Aug 2016 16:33:50 -0700 (PDT), trader_4 wrote:   > and most others that don't have this or does my WH and others have > some other way of thermal cut off instead that yours doesn't have, > thereby leaving yours unsafe? IDK   IDK either.   The book resistance of the Honeywell CQ100A1013 thermocouple is apparently 0.2 ohms but that's all I could find out by way of technical specs from either Sears or from Honeywell.   Sears confirmed the replacement part number is 9000056015, but when I look up *that* part number, none of the pictures show the thermal switch.   The fit of the Honeywell CQ100A1013 "universal" thermocouple isn't even close to the same as the original fit either as the mounting for the original is screwed on with a plate while the "universal" Honeywell thermocouple is a screw on nut which doesn't have a corresponding mating female.   Therefore, the "universal" thermocouple isn't even close to universal, although I can probably bend some metal to make it fit - I'm basically making my own parts out of raw materials.   When I called Honeywell technical support at 800-468-1502x1x1x9x1 to find out if they have a closer replacement than the Honeywell CQ100A1013 that I bought, they drove me nuts in so much as they don't even understand the simplest thing about the product they sell.   All they could tell me is that it has to go 1/2 inch into the flame.   When I asked for a thermocouople with a theroswitch, they told me to use the Q340A1074 but that doesn't seem to have a thermoswitch either. https://www.amazon.com/Honeywell-Q340A1074-International-Thermocouple/dp/B00E0CWKPC   So I'm basically making my own parts from raw materials because the mounts aren't even close on *any* of these so-called replacement thermocouples.

"Danny D." <dannydiamico@yahoo.com>: Aug 20 04:13AM On Sat, 20 Aug 2016 01:21:37 +0000 (UTC), Danny D. wrote:   > So I'm basically making my own parts from raw materials because the mounts > aren't even close on *any* of these so-called replacement thermocouples.   I concluded the "universal" mount stood zero chance of fitting. http://i.cubeupload.com/mYJNjq.jpg   There is just no way a "universal" thermocouple is going to stay put there. http://i.cubeupload.com/8G0mAF.jpg   Just look at this bracket for my original thermocouple. http://i.cubeupload.com/vQVXGL.jpg   For now, I sandpapered the thermocouple and put it back in, but I think I'll either have to find an exact replacement or build my own bracket assembly.   I can't believe everyone runs into this fit problem. Do you?

Retired <Retired@home.com>: Aug 20 08:24AM -0400 On 8/20/16 12:13 AM, Danny D. wrote: > assembly.   > I can't believe everyone runs into this fit problem. > Do you?   According to this A O Smith webpage, see page 18 at http://www.hotwater.com/lit/training/320991-000.pdf   "the thermocouple is not a separate replaceable part."   "There is no routine service associated with the TCO"   "The TCO is an integral part of the thermocouple and not replaceable as a separate item. A pilot burner assembly must be reinstalled."   See picture and instructions on page 20   Not knowing your specific model & serial numbers, 2 possible parts are shown at https://www.wallingfordsales.com/products.asp?cat=564&pg=68 P/N's 9006013005 or 9006014005

"pfjw@aol.com" <pfjw@aol.com>: Aug 20 08:06AM -0700 Nomenclature is your problem here.   a) A THERMOCOUPLE is a bi-metallic device that generates small amounts of electricity when heated.   b) A THERMAL SWITCH is a device, typically filled with mercury or some similar material that when heated to a specific temperature - or higher - closes a switch by expansion. From 3', you would not be able to tell one from another.   THEY ARE NOT INTERCHANGEABLE. Full Stop.   c) A THERMAL FUSE such as the one you picture is also a bimetallic device that opens at a specific temperature. Some such devices will reset, some will not. Most will cycle only a few times before they fail altogether.   You will have to purchase THAT and ONLY THAT part for replacement. Call the manufacturer of your heater and get the part number. Local suppliers such as Ferguson may have them, or any good plumbing supply house. This is very unlikely to be a Home Depot or Ace Hardware device.   Do yourself and your family a favor and don't spend 10 days trying to kluge something stupid that either won't work, be dangerous or worse. Save your gas, their sanity and their time. Just get *THE* *RIGHT* *PART* the first time.   NOTE: If the water heater is more than 10 years old, replace it. It will be done anyway shortly and you may as well do it now. Given that the replacement is $143.00, think hard before buying a part over a new unit.   Peter Wieck Melrose Park, PA

"pfjw@aol.com" <pfjw@aol.com>: Aug 20 08:13AM -0700 Just to be clear - as you often need a clue-stick applied repeatedly to clear the blather:   a) A THERMOCOUPLE operates by holding a magnetic pilot light valve open by generating small amounts of electricity. If the pilot fails, the electricity stops and the valve closes.   b) A THERMAL SWITCH holds an electrical switch closed by pressure.   c) A THERMAL FUSE opens at a specific temperature.   Do you even know which part has failed? Are you even contemplating bypassing the thermal fuse? Do you care that little for your family?   Peter Wieck Melrose Park, PA

avagadro7@gmail.com: Aug 19 04:21PM -0700 > more air moving over an operating exchanger gives cooler temps...otherwise the system needs repair.   > try wiring the fan directly to the battery with a relay. prob the ground side.   > first check for leaks in the output side n close down vents not needed.   Bing has the word   https://en.wikipedia.org/wiki/Zeotropic_mixture

"Ron D." <Ron.Dozier@gmail.com>: Aug 19 10:43PM -0700 Defrost always runs the compressor though, so in the winter everybody uses it. At least in cars I've had. =====   in a 1972 Chevelle, the AC and Defrost was linked although it may have been possible that at full hot, the AC got turned off. I can't remember, but i suspect not.   An 82 Celica allowed independent AC compressor on and off and a 2000 Chevy Impala did the same thing.

Micky <NONONObobbyburns1111@gmail.com>: Aug 20 07:20AM -0400 On Fri, 19 Aug 2016 22:43:32 -0700 (PDT), "Ron D." >=====   >in a 1972 Chevelle, the AC and Defrost was linked although it may have been possible that at full hot, the AC got turned off. I can't remember, but i suspect not.   >An 82 Celica allowed independent AC compressor on and off and a 2000 Chevy Impala did the same thing.   The 2000 Toyota turns the AC on when the defroster is turned on, but it can be turned off by pressing the AC button.   The 84, 88, and 95 Lebarons had a separate switch for AC, a mechanical switch where Off meant Off.   I don't think any of these cars had a MAX setting by that name.

Phil Allison <pallison49@gmail.com>: Aug 19 09:09PM -0700 Hi,   had one of these powered mixers on the bench this week - but without a clear fault report! The unit belongs to a church and was brought in by a regular customer, who did not use it personally.   The main problem proved to be similar, intermittent faults in both power amps - with very low and distorted (ie half sine wave) output when one or both were in fault condition. Both amps could work for periods of a hour or more between episodes of the fault condition.   The amp PCB did not respond to impacts or wiggling any multi-pin connectors and there are no rail fuses. So there was no option but to remove the heatsink and unbolt all 16 flat-pak devices to release the PCB.   This revealed a surprising situation - the solder on each leg of every TO3P device was visibly cracked, no need for a magnifying lens to see them either. Some devices almost fell of the PCB when it was released. Strangely, no other solder joints on the PCB showed any problems at all.   The unit is maybe 15 years old and looked well treated, so WTF was going on ?   The best hypothesis I have is the heatsink is the main culprit - it is a single piece of extrusion, about 20cm square, with raised, flat surfaces on opposite sides for two rows of TO3Ps bolted into threaded holes. The PCB itself is secured by 4 bolts fitted into stand-offs in a square pattern.   So, whenever the aluminium gets hot it expands and this pulls on all the flat-paks, tensioning the legs of each device against the solder joints. Do this thousands of times and fatigue cracks appear.   Not really sure if the solder was Pb free or not ( there is no marking on the unit ) but they all did have that dull look of the evil Pb fee stuff.   Anyone here seen the same thing before ?   BTW   The power amps use a really odd circuit topology called "EEEngine" by Yamaha - with six power Darlington devices, two of them operating as self oscillating, switching current sources.     .... Phil

bitrex <bitrex@de.lete.earthlink.net>: Aug 19 01:31PM -0400 I had some free time the other day and figured out the issue with my basket case i7 (bent power supply connection pin on the motherboard.) It's powering up now.   Unfortunately it looks like the ribbon cable connector has been damaged for the SATA drive on the mobo as well, so the clamp dosent "catch" with the cable when it's inserted and the clamp pressed down. I considered taping it in but on this type of connector, where it isn't a friction fit, I don't think it will apply enough pressure to keep it secure.   Any suggestions? Dab of superglue or hot glue gun, maybe?     --     ----Android NewsGroup Reader---- http://usenet.sinaapp.com/

John Robertson <spam@flippers.com>: Aug 19 11:02AM -0700 On 08/19/2016 10:31 AM, bitrex wrote: > connector, where it isn't a friction fit, I don't think it will > apply enough pressure to keep it secure.   > Any suggestions? Dab of superglue or hot glue gun, maybe?   Superglue would be my last resort - you don't want it working its way into the electrical contacts...   I am not familiar with something called an i7 (or 'mobo' either for that matter - is this some sort of phone? You sent this with an android, so perhaps this is android speak?), but assuming a standard SATA drive connector that isn't making good contact I would consider using a stronger bond that hot-melt - which doesn't stick that well to stuff. Perhaps contact/rubber cement? Or an adhesive putty like the stuff used to hang posters on walls?   John :-#)# -- (Please post followups or tech inquiries to the USENET newsgroup) John's Jukes Ltd. 2343 Main St., Vancouver, BC, Canada V5T 3C9 (604)872-5757 or Fax 872-2010 (Pinballs, Jukes, Video Games) www.flippers.com "Old pinballers never die, they just flip out."

MJC <gravity@mjcoon.plus.com>: Aug 19 07:49PM +0100 In article <jr-dnT-yP7YG1CrKnZ2dnUU7-InNnZ2d@giganews.com>, spam@flippers.com says...   > I am not familiar with something called an i7 (or 'mobo' either for that > matter - is this some sort of phone? You sent this with an android, so > perhaps this is android speak   Pretty certain mobo=motherboard, but I think "i7" is too enigmatic, as well.   Mike.

Jon Elson <jmelson@wustl.edu>: Aug 19 02:03PM -0500 MJC wrote:   >> perhaps this is android speak   > Pretty certain mobo=motherboard, but I think "i7" is too enigmatic, as > well. Intel core processors are available in i3, i5 and i7 versions.   Jon

bitrex <bitrex@de.lete.earthlink.net>: Aug 19 03:42PM -0400 >> well. > Intel core processors are available in i3, i5 and i7 versions.   > Jon   Yup. It's a Wintel laptop mobo, with a Core i7 processor. Sorry that wasn't clear. --     ----Android NewsGroup Reader---- http://usenet.sinaapp.com/

"jfeng@my-deja.com" <jfeng@my-deja.com>: Aug 19 01:02PM -0700 You can get pc-board mount SATA data connectors on eBay. This seller has 2 for $3.79+$0.80(shipping) http://www.ebay.com/itm/2-Pcs-New-Sata-7-Pin-DIP-Straight-Female-Connector-For-Hard-Drive-HDD-/181864444077?hash=item2a57f730ad:g:gfkAAOSwQ15XOX7X   and 10 for $5.99, shipping included http://www.ebay.com/itm/10-Pcs-Sata-Type-A-7-Pin-Straight-DIP-Male-Connector-For-Hard-Drive-HDD-/181691160057?hash=item2a4da315f9:g:jBYAAOSwcvdXOX0A   If you want the combo data/power connector, it is also 10 for $5.99, shipping included http://www.ebay.com/itm/10-Pcs-New-Sata-7-15-Pin-Straight-DIP-Female-Connector-For-Hard-Drive-HDD-/171977931322?hash=item280aaefa3a:g:BIkAAOSwxehXOX89   Same prices for connectors of the other gender.   Disclaimer: I know nothing about this eBay vendor, but I have purchased from other vendors on eBay.   I assume you will have no problems finding replacement data cables.

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