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Cursitor Doom <curd@notformail.com>: Apr 11 10:03PM Hi all,   Earlier I needed to do something with my graphing calculator. It only gets used very rarely so I wasn't surprised when it didn't switch on. I immediately suspected the batteries, but they were fine. All the same, I slipped in a brand new set. Still nothing. In the battery compartment they have an arrangement of 4xAAA cells in series to give a 6V supply. However, on checking the voltage from 'head to toe' as it were (from the first '-' to the last '+') I got a reading of minus 3V instead of the plus 6V I'd expected. Checked all the connections and the probes in the right sockets and whatnot: all fine. I'm sure I've had this issue before with a different battery appliance in the dim and distant past but can't recall what the cause was. It's like it's too far in the back of my mind to resurrect any more. :( Can anyone assist, please?

"Gareth Magennis" <soundserviceleeds@outlook.com>: Apr 11 11:37PM +0100 "Cursitor Doom" wrote in message news:ocjjrp$tjr$5@dont-email.me...   Hi all,   Earlier I needed to do something with my graphing calculator. It only gets used very rarely so I wasn't surprised when it didn't switch on. I immediately suspected the batteries, but they were fine. All the same, I slipped in a brand new set. Still nothing. In the battery compartment they have an arrangement of 4xAAA cells in series to give a 6V supply. However, on checking the voltage from 'head to toe' as it were (from the first '-' to the last '+') I got a reading of minus 3V instead of the plus 6V I'd expected. Checked all the connections and the probes in the right sockets and whatnot: all fine. I'm sure I've had this issue before with a different battery appliance in the dim and distant past but can't recall what the cause was. It's like it's too far in the back of my mind to resurrect any more. :( Can anyone assist, please?       ********************************************************     You are not checking from "head to toe".   You might think you are, but you are not.     Gareth.

Cursitor Doom <curd@notformail.com>: Apr 11 11:24PM On Tue, 11 Apr 2017 23:37:29 +0100, Gareth Magennis wrote:   > You are not checking from "head to toe".   > You might think you are, but you are not.   You were right! However there's still something not right about the continuity of the battery caddy. Unfortunately I can't go any further tonight partially due to the stupid modern prods you get with the absurd amount of shrouding which is making it impossible for me to 'get right in there' as I would like (and these prods don't have the removable shrouds). So it'll have to wait til tomorrow when I can get some more suitable ones. :(

mike <ham789@netzero.net>: Apr 11 09:23PM -0700 On 4/11/2017 4:24 PM, Cursitor Doom wrote: > there' as I would like (and these prods don't have the removable > shrouds). So it'll have to wait til tomorrow when I can get some more > suitable ones. :(   Take the socket from a PC power supply IDE disk power connector without the plastic part. Solder a short piece of piano wire to one of the connector sockets. Fits nicely over typical DVM probes and can fit into small places for probing battery sockets.

"pfjw@aol.com" <pfjw@aol.com>: Apr 12 08:52AM -0700 I have a few vintage battery power radios that have multiple voltage take-offs (taps) at various points within the battery case. One (uses six (6) D-cells) has the 9V end-to-end, a 3V-from-two tap, and a 1.5V tap for the intermittent dial-light. Another using four has taps at 6, 3 and 1.5. It would not surprise me if your calculator had similar conditions.   Clean the contacts. Check for broken or cracked connections. Check each individual cell for the correct voltage (and polarity!!! - ask me why!) prior to installing. I expect this is a mechanical issue in any case.   If you have something like a flashlight to test batteries, that is best as some will give 1.54V, but not enough current to do anything.   Once upon a time, I came across a set of very, very cheap (from China) knock-off duracell (small D deliberate) batteries, D-cells in 4-packs. Of the eight batteries, two were "packaged" backwards - the button at the negative end, the flat on the positive end - one in each package. So, I ask.   Peter Wieck Melrose Park, PA

Tomos Davies <cariadmenywod@gmail.com>: Apr 11 10:37PM Given that you can have manufacturers' red and yellow match mounting balancing dots can occur at any location on the tire sidewall, which, theoretically, is the "most balanced" tire (out of the box) when chosen out of a large selection of tires? a. When the red and yellow dots are at or near the same location b. When the red and yellow dots are about 180 degrees apart c. When the red and yellow dots are about 90 degrees apart   We all know that the yellow dot is usually the tire light spot (to be matched with the wheel heavy spot which is almost always the valve) and that the red spot is generally the tire out-of-round (aka radial runout & radial force variation) sidewall-thickness spot (which also is to be mounted at the tire valve in most cases).   While the red dot wins (if both dots exist) unless the wheel is so new that the match-mounting marks are still visible (and accurate), the question I ask has never been asked by anyone to my knowledge.   The reason this question has never been asked is probably because it's an engineering question, mostly theoretical, since you can mount the tire any way you want and still balance it just fine with the proper equipment.   So I ask the THEORETICAL question only to learn more about tires.   Given that you can have manufacturers' red and yellow match mounting balancing dots can be found at any location on the tire sidewall, which, theoretically, is the "most balanced" tire (out of the box) when chosen out of a large selection of tires? a. When the red and yellow dots are at or near the same location b. When the red and yellow dots are about 180 degrees apart c. When the red and yellow dots are about 90 degrees apart

"pfjw@aol.com" <pfjw@aol.com>: Apr 12 04:08AM -0700 On Tuesday, April 11, 2017 at 6:37:02 PM UTC-4, Tomos Davies wrote: > a. When the red and yellow dots are at or near the same location > b. When the red and yellow dots are about 180 degrees apart > c. When the red and yellow dots are about 90 degrees apart   The troll is back. Please don't feed the troll.   This is yet another alias using the name of a quasi-famous individual, not military this time.

avagadro7@gmail.com: Apr 12 06:14AM -0700 find a qualified shop with a road force machine   https://www.google.com/#q=auto+tires+road+force+balancing&spf=68   heavy tires, here LT heavy tread n multiple belts, do not balance without finding a balancing relation between rim and tire ...that is the tire needs rotating after the first try to a balance point agreeable with the rim. Then the unit is balanced.   the machine senses sidewall wobble ...with the heavy tire ....n suggests a balance point for eliminating sidewall wobble.   more than your dots question.

thekmanrocks@gmail.com: Apr 12 06:30AM -0700 I know a shop here in CT that *had* a road force balancer, but actually went back to a standard unit! Said something about technicians getting "inconsistent results" with it, so they went back to the simpler model.

Stephen <stephen_hope@xyzworld.com>: Apr 11 07:51PM +0100 >>consistent.   >Exactly so. This is common with flash-based systems. The power >system has to guarantee at least the current block has been written.   Well - not really. What can you do with an app that is running and doesnt keep files in a "safe" state?   Even some working apps dont leave files in a consistent state while idle (although agreed that is bad design).   Less said about malware busy scribbling all over your drive to maximise the chance of coming back to life after a reboot the better...   The point is that an operating system cannot make assumptions about what programs are trying to do and having "well formed" behaviour - they need to try to be robust no matter what is mucking around, while a disk is full and a drive is trying to remap to sort out bad sectors. >but they were there, so the were tested.   >It's a really good idea to test your system backups from time to time, >too. You may find the restore doesn't work. :-(   But the only true test of a restore is to actually wipe and restore on the same hardware build - when it is too late to find out it didnt get recorded correctly if you only have 1 machine (or 2 with different builds)......   >>Moral of the story: always try any new hardware during the warranty period!   And keep the old one as a fallback....   >Anything that's important has to be tested. Stephen Hope stephen_hope@xyzworld.com Replace xyz with ntl to reply

Stephen <stephen_hope@xyzworld.com>: Apr 11 07:52PM +0100 On Sun, 9 Apr 2017 15:34:01 +0100, MJC <gravity@mjcoon.plus.com> wrote:     >Conversely the possibly apocryphal story I heard had the generator >tested regularly. When eventually needed it ran for a few minutes and >then ran out of fuel. The protocol didn't include top-ups!   We had one where someone spoofed the guage and drained the tank.   >Mike. Stephen Hope stephen_hope@xyzworld.com Replace xyz with ntl to reply

jurb6006@gmail.com: Apr 11 09:01PM -0700 >"Of course. There are morons designing stuff all the time. Worse,there are companies that don't care that they're making crap."   Worse is that of companies, at least in consumer electronics WANT them to fail. I have seen examples that are pretty sure. Like in the five volt power supply they have an extras AC feedback loop which can only make the line vary. I beleive they did it corrupt the software. But then you could get the software "update" but wouldn't they just use better capacitors, or not do anything else ? I could find the reference to it under duress, but I am saying that they spend extra copper on the board to put certain caps near the vertical IC.   Like people say the government does so many stupid things, For some of them, they have a reason.   I have also seen alot of shit in audio like that. And this did not start yesterday either. I think they want(ed) to keep their jobs, so some units must fail. Their paychecks come from the sale of new units. Same with management.   It really comes down to screwing the People.

jurb6006@gmail.com: Apr 11 09:09PM -0700 >">>Moral of the story: always try any new hardware during the warranty period!   And keep the old one as a fallback."   Guilty. I bought a bunch of laptops and one stayed in the box past the warranty. I have had people try that so many times that I didn't even bother calling them, I just shelfed it. Luckily later, I got to use some of the parts.

Cursitor Doom <curd@notformail.com>: Apr 11 09:28PM Hi all,   I finally got around to taking a look at our tumble dryer, which has been out of action for a while (SWMBO's nagging finally paid off for her). In order to get it spinning round, you have to give the drum an initial shove, after which it rotates totally fine. But it cannot revolve without that artificial boost at start-up. I don't deal with repairing this kind of gear, but still fixed it within 5 minutes anyway. The 7uF/400V cap that lies strapped to the motor was faulty (had gone completely open-circuit). It was the first thing I checked. Nevertheless, I'm still unsure what exactly this cap's purpose is. AIR, they are often referred to as 'motor-start caps' or 'motor-run caps' but why are they needed? I'm guessing if they weren't used then manufacturers would have to fit more powerful motors simply to overcome the start-up inertia and a cap is cheaper than a heftier motor. But that's just a guess. Can some kind soul disabuse me of my ignorance here, please?

Foxs Mercantile <jdangus@att.net>: Apr 11 04:55PM -0500 On 4/11/2017 4:28 PM, Cursitor Doom wrote: > Nevertheless, I'm still unsure what exactly this cap's purpose is. > AIR, they are often referred to as 'motor-start caps' or 'motor-run > caps' but why are they needed?   Typical motors don't have to torque to start turning on their own. The start winding in series with the start capacitor provides the torque to start the motor. There's a switch to disconnect the capacitor after the motor comes up to speed.       -- Jeff-1.0 wa6fwi http://www.foxsmercantile.com   --- This email has been checked for viruses by AVG. http://www.avg.com

etpm@whidbey.com: Apr 11 04:11PM -0700 On Tue, 11 Apr 2017 21:28:41 -0000 (UTC), Cursitor Doom >would have to fit more powerful motors simply to overcome the start-up >inertia and a cap is cheaper than a heftier motor. But that's just a >guess. Can some kind soul disabuse me of my ignorance here, please? A single phase induction motor won't spin up without a push. This is because until the motor is spinning there is no ratating magnetic field. There are many ways to do this. One way is to use a starting capacitor. This cap is connected to a different winding, called the start winding, than the run winding and causes a phase shift, about 90 electrical degrees to the run winding. This gives the rotor a direction to start spinning. There is a centrifugal switch that takes the cap out of the circuit once the motor is about 85% of rated speed. If left in circuit the start winding would overheat. Another cap scheme is to have a cap that starts the motor and stays in circuit. This scheme doesn't provide as much starting torque but does have the advantage of simplicity and making the motor run smoother. There are also motors with switched start caps and always in circuit run caps. Eric

Rheilly Phoull <rheilly@bigslong.com>: Apr 12 09:15AM +0800 > advantage of simplicity and making the motor run smoother. There are > also motors with switched start caps and always in circuit run caps. > Eric   Most dryers I've seen have a "Run" cap only. I.e it stays in circuit all the time, much smaller rating than a "Start" cap and typically 7uF.

etpm@whidbey.com: Apr 11 05:17PM -0700 I'm sure someone here can help. I need to get power to a solenoid operated valve spinning at 5000 RPM. Low power, 24 volts at 5 watts. The power will be on for about 4 seconds and off for 7 seconds. This on/off cycle will be going on 10 hours a day. I have looked at slip rings online but the high speed through hole type are really spendy. Then I got to thinking about the slip rings in alternator. They certainly can carry enough current but I don't know how fast alternators typically spin. I do have an old alternator that would make a good slip ring donor. Anybody know or have a better idea? I need about 1 inch diameter through the slip rings. Thanks, Eric

Rheilly Phoull <rheilly@bigslong.com>: Apr 12 09:11AM +0800 > need about 1 inch diameter through the slip rings. > Thanks, > Eric   Not sure which "alternator" you have but a U/S vehicle one would yield what you want most likely, probably you could mod the brush holders too.

avagadro7@gmail.com: Apr 11 10:04AM -0700 > Probably on a global scale. Given all the various magnetic fields in and around the earth, given the differences in resistance from location to location (on land) and more, I am sure there are all sorts of micro-variations. But ground potential at any given point will be whatever is needed - that is, able to take 100% of what is 'above ground' relative to it. Which is what is measured (at that point) in any case, correct?   > Peter Wieck > Melrose Park, PA   I doahn know. Searching does not in short time lead to pursuable paths.   My experiments in the area define the concept as behaviorally and then functionally positive pursuing action within the arrived at elevated or depressed electric charge space.   From there awareness of time differences.....1950 vs 2010 ....in environmental charges coming from rubber on cement, electrical line discharge, the gamut...for behavioral response to the environment is clearly yes it does this in a significant way.   This does not agree with your response. Link to the plumbing ?   The question posed here is based on a probably fictional number for stable microvolt flow in and out of the ground. A not available number ?

"pfjw@aol.com" <pfjw@aol.com>: Apr 11 10:56AM -0700 You write in pretzels, not clear English.   At the scales you are positing, there are very few things that humans could do that would affect global static potential. If the concept of a marble containing a large amount of iron and maintaining a significant magnetic field, traveling in a moderately hard (but by no means perfect) vacuum around a much larger magnetic field that is continuously spewing massive quantities of various particles, some charged, some not, some fast, some slow, some massive (in the realm of particles) and some not lets you see a way that rubber on concrete, even large amounts of it relative to human size and weight, will materially affect ground-voltage other than _very_ locally - I would like *that* explained.   No matter how arrogant Mankind might be, we are still barely the equivalent of light mold on an orange. And as far as the earth is concerned, various sorts of mold have come and gone with no material effect on the planet itself - not on any sort of galactic scale. We may render the planet inimical our particular type of mold, but as it happens, the earth just does not care as in the fullness of time, some other sort will come along.   Peter Wieck Melrose Park, pA

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