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markcriscabanilla12@gmail.com: Aug 20 06:19PM -0700 Hello Can I get the solutions manual of Principles of Electronics by Malvino 7th edition. Thanks

"Michael A. Terrell" <mike.terrell@earthlink.net>: Aug 21 10:54AM -0400 > Hello Can I get the solutions manual of Principles of Electronics by Malvino 7th edition. Thanks   Do you really think that the spammer comes back to look for replies?

jurb6006@gmail.com: Aug 20 10:08AM -0700 According to   http://www.yamahaproaudio.com/global/en/training_support/selftraining/technology/eeengine.jsp   They are effectively using transistors as active filters for switching regulators, pretty much like class D.   High frequency and current are not nice to solder. Some TV manufacturers used eyelets at the connections to the horizontal (lie) output transistor for this reason. The transformer as well.   I've seen that topology before, may have been Yamaha, or some other brand. I don't know if they have it patented or not, or if it is patentable or worth patenting. Crown apparently patented their grounded bridge, how enforceable it is is another story. I think it would be pretty hard to prosecute.   I see this one is actually DC coupled, but there may have been no other way to make it work. Not sure.

Phil Allison <pallison49@gmail.com>: Aug 20 07:03PM -0700 > http://www.yamahaproaudio.com/global/en/training_support/selftraining/technology/eeengine.jsp   > They are effectively using transistors as active filters for > switching regulators, pretty much like class D.   ** A better description is that the class B output stage includes signal tracking supplies for each rail employing switching, buck regulators.   The attraction of this example is the extreme simplicity and low parts count - in part made possible by the use of Sanken power Darlingtons rated at 70MHz.   http://www.semicon.sanken-ele.co.jp/sk_content/2sd2560_ds_en.pdf     .... Phil

John Robertson <spam@flippers.com>: Aug 20 10:54AM -0700 On 08/19/2016 7:16 PM, Phil Allison wrote:   > ..... Phil   Hi Phil,   My point was one has to be careful with what cap you choose to replace the original. Too low an ESR may over stress the diodes. If the input is protected with a varistor or similar then indeed, I agree there isn't a problem, however if the bridge rectifier is directly connected to line (via xformer, etc.) then wouldn't lower ESR caps introduce a problem?   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."

ohger1s@gmail.com: Aug 20 05:18PM -0700 On Saturday, August 20, 2016 at 12:11:15 PM UTC-4, KenO wrote:   > 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.   NO! NO! NO! You're overthinking this again!!   It's simply a rectified and filtered AC supply. They've been building power supplies this way since the 1920s. It's simple and foolproof. Your rectifier is good, your cap is bad. The only external factor that could have caused your cap to fail is a weak or open neutral in your house's wiring that doubled the input voltage. But if that happened, you would notice other things, like light bulbs exploding..   Again, the cap in your TV was likely just a bad run of caps at least, and a poorly spec'd cap at most. Nothing caused it to fail, nor will the failed cap damage any LEDs. Further, shorted LEDs won't harm your AC bridge capacitor.   On a totally different subject, YES, lowering the back light in the menu (particularly in LED TVs) will extend the life of the back light exponentially. When I repair LED TVs for failed back lights, I always modify the LED drive circuit so that the LED array runs between 30 and 40 percent lower in wattage regardless of where the customer sets it or if it defaults back to full brightness. Customers don't notice and I don't have to worry about them coming back in warranty.

Phil Allison <pallison49@gmail.com>: Aug 20 06:54PM -0700 John Robertson wrote:     > Hi Phil,   > My point was one has to be careful with what cap you choose to replace > the original. Too low an ESR may over stress the diodes.   ** In the example given, the winding resistances of the switching tranny are gonna be way higher than the electro's ESR, overriding any effect changes in that value could cause.   Also, actual ESR is not clear from the published data as makers typically quote maximums at room temp. New caps may be half or less that value and in any case ESR drops with rising temp - by a factor of FIVE times more of the temp rises to 100C.     > If the input is > protected with a varistor or similar then indeed,   ** AC side thermistors or resistors help with inrush surges, but then normally have very little effect afterwards.   For practical purposes, the average value of the rectified current is all that matters, which does not change with C or ESR value.   Of course, the diode must be fast enough to handle the switching speeds with low loss.     .... Phil

"Danny D." <dannydiamico@yahoo.com>: Aug 20 05:47PM On Sat, 20 Aug 2016 08:24:06 -0400, Retired wrote:   > ccording 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."   Thank you for locating that training information as it sure does seem like they designed the $10 thermocouple to not be replaced easily!   The existing thermocouple is attached at two points, one of which is screwed on at the S-shaped 180 degree C thermoswitch (which seems easy to remove) but the other of which is seemingly firmly attached to a plate that also has the pilot light tube just as firmly attached.   So it seems that the thermocouple can't be 'wiggled' out, although I haven't tried using real force yet.   > "There is no routine service associated with the TCO"   It's only slowly dawning on me that the thermal cutoff switch (TCO) is making the thermocouple not "universal".   > not replaceable as a separate item. A pilot burner assembly must be > reinstalled."   > See picture and instructions on page 20   That manual was *fantastic*. Thank you for finding that!   I'm not sure how you knew I had an AO Smith hot water heater, but I do.   I called the residential service number listed in that manual at 800-527-1953 (x2 x2 x2 x1) and spoke to a very nice support person who explained that there are two filters that need to be cleaned just as described in that wonderful training manual. 1. Cordorite (she called it chromatic) anti-flame filter 2. LDO (she called it metal mesh) dust and anti-flame filter   > shown at > https://www.wallingfordsales.com/products.asp?cat=564&pg=68 > P/N's 9006013005 or 9006014005   The lady at AO Smith asked for my serial number, and given that, she told me what you said, which is that the thermocouple with Thermal Cutoff Switch is not replaceable.   She said I need the $88 MSRP pilot assembly PN 9003455005 which she said I should be able to get in San Jose at: - Slinky Brothers 408-494-7948 (7-4:30 M-F) - RV Cloud 408-378-7948 (they don't sell AO Smith anymore they said to try a place named "rubenstein on monterey highway who is not open on weekends) - TW Smith 408-249-9880 (they're not open on weekends)

Retired <Retired@home.com>: Aug 20 02:02PM -0400 <snip>   > That manual was *fantastic*. Thank you for finding that!   You're welcome       > I'm not sure how you knew I had an AO Smith hot water heater, but I > do.   > <snip>   FWIW, I did a Google Images "Search by Image" of one of your pics, and got a good hit on an A O Smith web page. (google is your friend ;-) )

"Danny D." <dannydiamico@yahoo.com>: Aug 20 06:33PM On Sat, 20 Aug 2016 14:02:54 -0400, Retired wrote:   > You're welcome   That manual was great. Nice color pictures. Nice explanation. And it had the all-important AO-Smith 800 number which is really good (and far better than Sears and Honeywell, both of which were horrid).   > FWIW, I did a Google Images "Search by Image" of one of your pics, > and got a good hit on an A O Smith web page. (google is your friend ;-) )   I'm amazed that your image search worked, but I appreciate you doing that as the sticker on the side of the AO Smith water heater had a sears number so I had called them first (and wished I had not) since they gave me the wrong part number (which I could tell was wrong from looking up what it looked like).   I called the AO Smith people back and got another nice person, who kindly is sending me, gratis, an AO Smith Filter cleaning kit PN 9006477005.   Googling, here is a picture of what I think they're sending me: https://www.johnstonesupply.com/storefront/product-view.ep?pID=N45-884   That google search also found this 2015 AO Smith parts catalog: https://www.hotwater.com/lit/catalogs/apcom_aos_catalog_w_slip_sheet.pdf   This seems to show two part numbers for the propane pilot assembly: 9003455005 & 100109243   I wonder if I should add the sacrificial anode to my list of parts to get?   Mine is under the hot water nipple, where the part number includes the hot water nipple where a minimum order is $50 at (800) 433-2545 AO Smith Sacrificial Anode 9009148005 $38 + $10 UPS Ground   Do you guys replace anodes at around 10 years?

"Danny D." <dannydiamico@yahoo.com>: Aug 20 06:35PM On Sat, 20 Aug 2016 12:39:36 -0500, CRNG wrote:   >>without the thermal fuse in and does it work? If it does, end of story >>on the resistance part.   > +1   I'm not a plumber so I don't know if the resistance matters or not, but I do know that the thermocouple generates 30mv which is puny so any additional resistance to the 24 inches of wire could make a difference and I don't know what the resistance of the 180C thermal cutoff (TCO) is.   If the 180C thermal cutoff adds appreciable resistance, then the resistance of a 24-inch universal thermocouple will be different than the resistance of this 24-inch thermocouple with TCO such that it won't be 30mv anymore.   But putting a replacement thermocouple seems to be far more difficult than people make it out to be, simply because AO Smith designed this as a non-replaceable part. It can only be replaced as a "pilot assembly", part number 9003455005.

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