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Jeff Wisnia <Jwisnia18@DUMPTHIScomcast.net>: Nov 06 03:49PM -0500 Lazy guy that I am, I installed "touch switches" in the bases of four metal bodied table lamps in our home.   It's a heck of a lot easier to just reach out and tap the lamps than to have to stretch and reach up under the lampshades to twist the typical socket switch knob. And, they provide four levels of illumination from an ordinary bulb.   I might add that shortly after I installed those switches about 15 years ago I learned the hard way that I had to install a fuse holder with a 2 amp fast blow 3AG fuse in the line going to the lamp bulb because when a bulb burned out sometimes a "tungsten arc" occurred and drew a surge of current large enough to fry the touch switch's electronics. Now, I only have to replace a 20 cent fuse along with the lamp bulb.   SWMBO and I were sitting on the sofa watching the November 2nd election returns when the lamp on the end table next to me turned off. I thought WTF? and touched the lamp which turned it on again. I went back to watching TV and a few minutes later the lamp turned off again.   I figured maybe the lamp bulb might have gotten loose in its socket or the lampshade loose on its stud and stood up to see if that was the cause.   When I looked down into the lamp shade I saw a ladybug crawling on the lamp socket. A few ladybugs join our family every fall, seeking warmth I guess.   I stood there and watched as that ladybug crawled up the side of the lamp socket shell and started to walk around the neck of the bulb.   The moment its legs touched both the lamp socket shell and the side of the bulb's screw base the lamp went out.   Mystery solved. The bug was creating a connection between the lamp body and the bulb's screw base (Said base was connected to one side or the other of the 120 volt line). That connection drew enough current out of the touch switch's sensing lead to cause it to react as if someone had touched the lamp and drawn enough capacitive charging current to activate it.   Who woulda thought it? I kicked that ladybug outdoors again.   Jeff -- Jeffry Wisnia (W1BSV + Brass Rat '57 EE) The speed of light is 1.8*10^12 furlongs per fortnight.

jurb6006@gmail.com: Nov 06 03:46PM -0800 Yup, needs a good debugging.

"hrhofmann@sbcglobal.net" <hrhofmann@sbcglobal.net>: Nov 06 08:39PM -0800 Great story!!

Jeff Wisnia <Jwisnia18@DUMPTHIScomcast.net>: Nov 07 11:19AM -0500 > Great story!!   And last nite it happened again. Don't know why the ladybugs favor that part of a table lamp. Might be they are going for the warmth coming from the lit bulb.   This time the lamp was being turned off and on intermittently every 5 or ten seconds. I looked down at the socket and the ladybug was crawling in a circle around the top edge of the socket shell. when its inside legs touched the top of the threaded socket the touch switch was triggered.   The ladybug didn't seem affected, it just kept crawling around the socket until I removed it.   IIRC I've heard of insects triggering some types of smoke detectors too.   Jeff   -- Jeffry Wisnia (W1BSV + Brass Rat '57 EE) The speed of light is 1.8*10^12 furlongs per fortnight.

"Mike Marlow" <mmarlowREMOVE@windstream.net>: Oct 30 05:17PM -0400 Danny D. wrote:   > She's brand new to teaching, but, it turns out that classroom > management is a standard problem in these multi-ethnic San Jose > schools.   Well - that's a big part of your problem. Rather than teaching kids things, parents and teachers rally around excuses for what the things exist. I wish you the best - deal with the problems you are creating.     > One teacher uses a bathroom plunger, as his bathroom pass.   Brilliant! Shear stupidity - so why shouldn't everyone else follow suit?   >> mention, an exercise in futility. What does this really accomplish?   > What it (attempts to) accomplish is the reduce undue interruptions of > the classroom environment.   Brain dead thinking. But that's fine - do that kind of thinking where you live. What in the hell do you really think you are solving with this kind of approach?     > jail, if > even for only 10 minutes (which they can synchronize with other > friends, if they're clever).   You just keep on letting those kids outsmart you. I'm sure you'll win that way...       > What the pass does, first and foremost, is it discourages such > intents.   Bullshit! Are you and the teachers at that school that stupid as to really believe this? If so - muck in your own mire.   > Also, it allows the teacher to continue teaching, > uninterrupted, as > the students just get up, grab the pass, and return, unannounced.   Really? Do you even think about the things like this that you post?     > something they can leave hidden in the hallway while they > surreptitiously run a'muck about the hallways or outdoors to catch a > smoke or whatever.   Dear Parent...       > Likewise, it prevents multiple kids (from the same classroom anyway) > leaving the room at any one time.   Really? The high paid teacher is this dumb as to not be aware of this syndrome? Really?     > or not. It's like the red sign on an airplane bathroom door showing > it's in use, rather than what we have to do at a McDonalds, which is > to jiggle the doorknob repeatedly to find out if someone is in there.   Yeah - when I was a kid I had a really hard time understanding a locked door - are you really this stupid? How about facilities that accomodate 4 kids at once - where does that fit into your foolish thinking?     > And, being so large (on purpose), the kids, who almost certainly don't > like it, can't lose it easily.   Oh man - that just can't be anymore stupid.     > At the very least, it's objectionable to carry (as you noted), which > would further discourage the unnecessary potty breaks.   Really? What in the hell is the problem you are looking to solve? I think you have a California mindset which just does not think at all.       > Rest assured, this teacher has at least one kid a day out of her 200, > walk out on the class without excuse.   Really? Then fire the teacher. That is her or his responsibility to make sure that kind of thing does not happen. Screw the 200 number - that's a classic over-exageration - how many students in any one class session? The total number is completely meaningless.     > all of which are common through all the classes, as she told me most > of these kids are being weeded out of the system through their > behavior in *all* their classes.   Guess you guys need to improve your school disciplines and forget looking at magic tokens like stupid wood fobs for a key to the boys room. Do you really belive that is going to fix the problems you guys have created in your schools? Really? Are you really that dumb?   > comments on their report cards of "very polite", "always helpful", > "pitches in to volunteer every time I ask", and even once "raises > hand to answer questions too often!".   Good for you! That's what is necessary - not stupid fobs.     > California, they go through 3 semesters of graduate training, to > obtain a preliminary teaching certificate, two semesters of which > have on-the-job training of sorts.   Kudos to you for trying to help a new teacher but don't you see that the problem is so much bigger than that?   > their preliminary teaching certificate cleared. At that point, they > also get tenure (which is kind'a soon, if you ask me), and then > they're bona-fide teachers.   Well - you might want to take the problem up with your school district. You guys created the problem and stupid ideas like wooden fobs is not going to fix that problem.     > training on "classroom management", which I found odd when I saw that > it's the *first* thing they re-train the preliminary-credentialed > teachers on.   Oh well...   > small percentage of the kids (maybe 1/3?) actually care to learn it. > It's a required class for the rest, which they hope to never see > again during the rest of their lives.   We have to remember? Really? Are you that stupid? They are in school. They are there to learn what they are told to be taught. We have to remember? I see the very root of this problem...     > When is the last time you or I graphed a quadratic equation, for > example? Could each of us solve a binomial equation to save our lives? > (Building suspension bridges in the redwoods notwithstanding... :)   Competely irrelevent! We did do it when we were in school. What does it matter at all when the last time was that we did it. I'll tell you that I have used that knowledge throughout my life - though it may not have been on a daily basis - but when I needed it, I could call on it. You are making excuses for dumbing down our already stupid kids even more?   --   -Mike- mmarlowREMOVE@windstream.net

sonnichjensen@gmail.com: Nov 06 10:31AM -0800 > Not necessarily. I as expecting to see the red cathode alot higher.   > Since you have dicrete video outputs and not a chip you can clip lead test it. Turn your brightness/cpntrasdty down and tak a 10 K resistor from the red cathode to ground. You should see red. Use a voltmeter and make sure the 10 K is pulling the red cathode voltage down below the other two. Once you see red get it off of there, in fact just stick the resistor in the end of a grounded clip lead. Use the connection to the CRT aquadag for a ground because we haven't determined what kind of power supply this thing has. Is might not be totally isolated, and you don't want to use the hot ground. If the 10 K doesn't pull it down to like 50 volts, try maybe an 8.2 K.   > Only connect this temporarily as it might result in excessive cathode current. Once you see the color that is enough. In fact go ahead and try the blue as well. Once the CRT is actually confirmed good, then it is a matter of working backwards.   I tried the colours, and they are all there. Now I tried another video source, and it does not work. The problem will have to be around the TDA3565, but I cannot see what it can be at the moment.

sonnichjensen@gmail.com: Nov 06 12:14PM -0800 > Not necessarily. I as expecting to see the red cathode alot higher.   > Since you have dicrete video outputs and not a chip you can clip lead test it. Turn your brightness/cpntrasdty down and tak a 10 K resistor from the red cathode to ground. You should see red. Use a voltmeter and make sure the 10 K is pulling the red cathode voltage down below the other two. Once you see red get it off of there, in fact just stick the resistor in the end of a grounded clip lead. Use the connection to the CRT aquadag for a ground because we haven't determined what kind of power supply this thing has. Is might not be totally isolated, and you don't want to use the hot ground. If the 10 K doesn't pull it down to like 50 volts, try maybe an 8.2 K.   > Only connect this temporarily as it might result in excessive cathode current. Once you see the color that is enough. In fact go ahead and try the blue as well. Once the CRT is actually confirmed good, then it is a matter of working backwards.   ok, I tried to check all wirering around the TDA3565 and signaling, and I cannot fint anything that seems to wrong. It is not the exact same as the datasheet, but close. No shorted condensators, resistors seem be ok.   Using my scope I have signals which seem to be ok. The contrast voltage can be adjusted (pin 6), but it has no affect whatever.   Maybe afterall it is the CRT

jurb6006@gmail.com: Nov 06 08:51PM -0800 Scope it right at the CRT cathodes.   If the thing is not old enough for aa pension (literally) it has all common elements of the tube except the cathodes. That is now the inpur no matter what.   I should've told you to do the green cathode with the resistor as well. If the green is really bright and the red is not, it is probably the CRT. With the same resistor, the red should be every bit as bright as the green, and maybe brighter. The blue not so much, some blue phosphors are not that strong. some of them are a really pure blue which inherently requires more current to push. The only tubes that had the really ineffieicent red phosphors were from the 1950s and abouts. then they found neodynium or someting, threw it in the phosphor and red was brilliant after that. Now if there is any problem, it is the blue.   Have you found the greyscale adjustments ? You know if it is the CRT, it might still be within limits to adjust. We used to do that all the time. You could have pots on the board or you could have it in the service menu.   It is normal for CRTs to become imbalanced over time, that is why there are adjustments.

David Lesher <wb8foz@panix.com>: Nov 07 01:24AM I have a orphaned Olevia TV that has just developed an ugly new symptom.   There are blooms/blotches of ~red appearing on darker scenes. It's most obvious on older B+E rerun shows such as Route 66 & I Spy. But I have seen them on low-def color shows.   I don't see them on network 720P feeds. At least now...   Any suggestions?     -- A host is a host from coast to coast.................wb8foz@nrk.com & no one will talk to a host that's close.......................... Unless the host (that isn't close).........................pob 1433 is busy, hung or dead....................................20915-1433

jurb6006@gmail.com: Nov 06 05:56PM -0800 That's not called blooming, but no big deal.   If the splotches are stationary and onbly in certain modes it is most likely decoding errors, and that is usually on the main board. If it was in all modes I would say it might be the panel or Tcon, but it isn't.   Slight possibility of it being bad caps, but very slight.   Try looking for settings that are channel or mode specific in the menu(s). Of you find them you might find the broghtness turned too low for one mode or sometning. Sometimes LCD panels "overtwist" which can do things like this. That is ALOT more noticable on an edgre lit display like a laptop PC. Regular backlit monitors are alot better about that now, unlike years before when they didn't have the viewing angle.   If it is overtwist, likely you will see a difference when you change your angle. I it looks significantly different from the left, right, above or below, just adjusting the brightness (pedestal) might fix you up. I do not mean in different places, I mean more or less pronounced.   Even if there is a minor fault, adjustments might make it watchable. Especially if it has a gamma control. I doubt it does, but if it does you can play with that.

bud-- <null@void.com>: Nov 06 02:24PM -0600 On 11/3/2014 10:19 PM, josephkk wrote: > pipe when metallic. Also bonding to the structural steel if there is > significant steel above ground. Enforcing article 250 et seq. has been > part of my job for the past 8 years.   There may be requirements other than the NEC where you are working.   The NEC requirements are:   - Power earthing may have one or many electrodes that are connected together as an earthing system (250.50).   - A metal water service pipe MUST be used as one of the earthing electrodes. It has been so since time began. Exact requirements have changed over time as more water services use plastic pipe. The requirement for many years is that a metal water service pipe in contact with the earth for 10 ft MUST be used as an earthing electrode. (250.50, 250.52)   - If the water service pipe is NOT metal-10ft, then the interior metal water pipe must be "bonded" to the power ground system (250.104-A). The connection as an earthing electrode (above) is more stringent than "bonding".   - Since a metal water service may be replaced by plastic, a "supplemental" electrode has been required for many years. Many kinds of electrode can be used (250.53-D). Often it has been a ground rod because they are easy to install.   - Gas piping must be "bonded" to the building ground system. The size of the bonding wire is determined by the current rating of the circuit that is likely to energize the pipe. In a house this is likely the feed circuit for a furnace, or similar device. "The equipment grounding conductor for the circuit that is likely to energize the piping shall be permitted to serve as the bonding means." (250.104-B)   - Gas service pipe may not be used as an earthing electrode.   - Structural steel may be required to be used as an earthing electrode (250.50, 250.52). Else it is required to be "bonded" (250.104-C). Connection as an earthing electrode is more stringent than "bonding".   - For new construction, if there is a concrete foundation or footing, a "concrete encased electrode" is required (250.50, 250.52) These are commonly called a "Ufer" ground. They are a good electrode (far better than a ground rod) and are used as the "supplementary" electrode for a water service pipe where both are present.   - Ground rods are required to be used as an earthing electrode "where present". They won't be present unless someone installs one. Installing one is not required. (250.50) Rods are 8 ft min, and the types used are 5/8" diameter. They must have a resistance to earth of 25 ohms or less, or else 2 can be used and there is no requirement (250.53-A-2).   Ground rods are among the worst earthing electrodes. If you connect a 120V circuit to a code compliant 25 ohm rod will it blow a 15A fuse?   If the only earthing electrode is a ground rod (which is compliant is some places), and the rod has a near miraculous resistance to earth of 10 ohms, and there is a surge to earth of 3,000A, the potential of the building "ground" is 30,000V above 'absolute' earth potential. In general, 70% of the voltage drop away from the rod is in the first 3 ft. Over 3 ft from the rod is at least 21,000V from the building "ground" system. If you have a rooftop TV antenna that is earthed only to a separate rod the coax will be over 21,000V from the power "ground". You may also get that on a metal gas service pipe, which is why very thin-walled CSST can be a problem.     What I wrote is consistent with NEC requirements. Installing earthing systems has been part of my job for the past ...um... lots of years.

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