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Ralph Mowery <rmowery28146@earthlink.net>: Sep 24 01:13PM -0400 In article <f7c85242-eb1c-4e21-b3f2-f187d14ac69e@googlegroups.com>, pallison49@gmail.com says...   > ** Heathkit ? 1kW ??   > FYI, there is ZERO phase angle between the V and I drawn by an amplifier.   I don't know how accurate it was, but a few years ago I replaced the tubes in my Sb-200 amp. I wanted to see how efficient the amp was.     I had an el cheepo China meter that showed Volts, amps, watts. The volts did check with my Fluke meter.   With a bathroom heater the watts and V times A were vey close maybe because of the very small fan motor. When hooked to my amp and loaded to 600 to 700 watts RF out the watts and V times A were way off. One showed maybe 80 to 90 $ different depending on the loading. I took that to be the inductance of the transformer causing that.   I don't know enough AC theory to explain it if there is not more than a ZERO phase angle.

Phil Allison <pallison49@gmail.com>: Sep 25 04:29AM -0700 Ralph Mowery wrote:   --------------------- > to be the inductance of the transformer causing that.   > I don't know enough AC theory to explain it if there is not more than a > ZERO phase angle.   ** The PF of general electronic load is about 0.5 to 0.65.   But that has NOTHING to do with transformer inductance ( a myth) or phase angle and cannot be fixed with a capacitor across the supply.   It has everything to do with the current wave be made up of pulses ( at double the supply frequency ) and so not being a sine wave.   The "true rms" value of a pulsed current is higher than a comparable steady sine current.       .... Phil

amdx <nojunk@knology.net>: Sep 25 08:19AM -0500 On 9/23/2019 10:11 PM, Phil Allison wrote:   > In any case, the current draw and power consumed off load is much lower.   > .... Phil   The reference was to the video where he used an unloaded motor. Then as you say, "current draw and power consumed off load is much lower". So how often do you run a motor unloaded and is it worth the cost of PFC. How often does a factory run a motor unloaded? Mikek

legg <legg@nospam.magma.ca>: Sep 25 08:59AM -0400 On Fri, 20 Sep 2019 16:29:16 -0700 (PDT), bruce2bowser@gmail.com wrote:     >I'd like to use dark mode but I can't, unless I reach for my wallet. That's because my iPhone 6, and older iPhones, won't be compatible with iOS 13, the forthcoming version of Apple's operating system. Owners of older iPads will be in a similar predicament. And owners of new Apple Watches but older iPhones won't be able to update their watches unless they get a newer phone."   >New York Times - August 23, 2019 >-- https://www.nytimes.com/2019/08/23/business/apple-watch-iphone-casio.html     $   RL

"pfjw@aol.com" <peterwieck33@gmail.com>: Sep 25 05:46AM -0700 As already noted, many things *can* get hot. What is in question is how heat will affect various components. In no particular order:   a) Carbon comp/film resistors will change value over time, and much more-so of heated. Some types are so awful that they will change in value simply from the heat required to install them. Given the alternatives, the only reason to use them today would be based on audiophoolery.   b) Electrolytic capacitors do not like heat at all. Sure, the come rated to 105 C. and more - but none-the-less, they continue not to like heat. In general, if an electrolytic cap in a piece of solid-state equipment gets warmer than ambient temperatures, replace it!   c) Cold-solder joints will get hot based on the current they may be carrying. And, in general, there will be some discoloration around the bad joint, or some other visible indication. Most especially if this bad joint is of long standing.   d) Broken/lifted/oxidized traces are very often heat related. And in the last stages before complete failure they may become intermittent, giving you the symptoms you hear/see.   e) If, by any chance there are small IF cans on/near this board, or within this device, silver-mica disease will create thunderstorms and breathing symptoms as the equipment heats up.   If you have access to an IR camera, try running that board until the symptoms are well-established, then pull it and photograph it. A hot component will stand out as a bright white blob. A friend of mine is a hobby photographer and has IR equipment. One day, he decided to use it to troubleshoot a piece of electronics. Within a few minutes he found the problem - that was otherwise entirely invisible under normal light.   Peter Wieck Melrose Park, PA

Michael Terrell <terrell.michael.a@gmail.com>: Sep 24 11:26AM -0700 On Tuesday, September 24, 2019 at 9:51:23 AM UTC-4, John-Del wrote:   > > .... Phil   > I can promise you that if you saw several of these a month, you would have by now acquired both the equipment (cheap enough) and the skill to do this in your sleep.   > Although SMD requires a learning curve, it is not difficult if the tech has decent hands and magnification.     It only took me abut 15 minutes to learn on 1206 & 0805 components, over 22 years ago. It wasn't long before I was working with 0402 and the occasional 0201 sizes which required a stereo microscope, due to my life long vision problems.

Ralph Mowery <rmowery28146@earthlink.net>: Sep 24 02:56PM -0400 In article <0c05ba1d-a671-484b-af34-dee126ba3f47@googlegroups.com>, terrell.michael.a@gmail.com says...   > > Although SMD requires a learning curve, it is not difficult if the tech has decent hands and magnification.   > It only took me abut 15 minutes to learn on 1206 & 0805 components, over 22 years ago. It wasn't long before I was working with 0402 and the occasional 0201 sizes which required a stereo microscope, due to my life long vision problems.   I don't know about those modules, but for about $ 500 or less you can get set up for SMD repair. I bought the Stereo microscope for $ 200, and a cheep hot air and soldering iron setup for about $ 70. This is a hobby, I would spend about 3 to 4 hundred for a good hot air station if repairing them all the time. Then a few more dollars for fine solder and tweezers.   I watched youtube and practiced on some old computer boards. I was 65 at the time. There may be some components that have multi leads under the device that may require lots of practice.

John-Del <ohger1s@gmail.com>: Sep 24 12:49PM -0700 On Tuesday, September 24, 2019 at 2:57:04 PM UTC-4, Ralph Mowery wrote: > hobby, I would spend about 3 to 4 hundred for a good hot air station if > repairing them all the time. Then a few more dollars for fine solder > and tweezers.   And FLUX! Flux is a magic elixer when it comes to SMD work.     > I watched youtube and practiced on some old computer boards. I was 65 > at the time. There may be some components that have multi leads under > the device that may require lots of practice.   Many modern SMD ics use a heat sink belly pan even if the IC has conventional leads. These must be heated by air to release the bottom pan. I've even seen 8 pin buck ICs that look totally conventional, but have a belly pan.   Before removing, check the datasheet to see if it has one. If it doesn't have a belly pan, blob both sides of the IC and lift off with tweezers.   One trick I taught my students was to take a Dremel and *carefully* mill down the top of the defective IC until the die of the IC was exposed. In this way, the IC would heat much more quickly from the top and release in far less time in order to reduce collateral damage to the PC or surrounding devices.

Ralph Mowery <rmowery28146@earthlink.net>: Sep 24 05:24PM -0400 In article <ec79a806-7232-427a-b119-82a2d991b8d6@googlegroups.com>, ohger1s@gmail.com says...   > And FLUX! Flux is a magic elixer when it comes to SMD work.   Yes, some good flux. Usually the real thick kind in the things that have plungers and look like a big shot.   As that woman on you tube (Jessica Jones or James or something) said 'they like copper, heat and flux'.

jsc1210@gmail.com: Sep 24 12:33PM -0700 Hi Chery -   This is a late response, but perhaps it will help someone else.   I could not follow some of your descriptions of on/off actions. Here is what I recommend. Turn off all circuit breakers that go to your Vantage modules, then turn them all on. If you have one enclosure, your CPU (master controller) will be rebooted by one of the circuit breakers. This is good. It will take a minute or so for it to reboot. If all works, you are good. If nothing works or you have more than one enclosure and only some light switches work but others do not, you have problems so continue reading.   Now you want to try to manually control individual circuits. There is a feature called Override which permits you to test without allowing the CPU do the work. In the master enclosure (has the CPU), there is an Manual Override switch. If the enclosure is not the master, then the Override feature may be linked to the master enclosure (this is normal) or it could be configured to only override that enclosure.   When Override is switched 'on', you can control individual loads/lights. This accomplished by the 8 micro white switches on the top of each module in the enclosure. Switch up = on, switch down = off. If you can control each load then the 8-load module is not the problem. If you cannot control anything unless Override is active, a controller is suspect - either master or slave.   When the enclosure is a 'slave' enclosure (2nd, 3rd, ... enclosure), if the CPU location in that enclosure is filled with an aluminum box, you have a slave controller for that enclosure. I have seen Master and Slave controllers fail due to lightening. The weak point in both is the power supply in those boxes. Replace those boxes and you will be good to go. A slave controller only needs to be replaced - no other action necessary. If it is a master controller, it will have to be programmed with your configuration. Hopefully that programming is available to you.   If the slave enclosure has no aluminum box that reads 'Slave Controller', you have the newer InFusion configuration and will only see a circuit board at the bottom of the enclosure. For these, there is no slave controller to contend with.

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