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Mad Roger <rogermadd@yahoo.com>: Jul 21 04:51PM On Thu, 20 Jul 2017 17:32:39 +0100, Mike Coon wrote:     > Trip meter miles depends on circumference of driving wheels. I know my > speedo closely matches readings of roadside radar displays or my GPS, so > I guess trip meter miles will be accurate too.   Every reading a mom and pop does has inaccuracies that, I posit, are tremendously higher than most people seem to think they are (at least most people who quote mpg figures with decimal places in them).   Most people have a tripmeter reading and a gas pumpmeter reading. Where they fill the tank and reset the tripmeter before driving away.   I can't find any reliable source that says what the accuracy or repeatability of that mom-and-pop tripmeter/pumpmeter calculation, but basic logic dictates that the errors compound such that there is likely (IMHO) no way to get anywhere near decimal-point accuracy, and worse, probably plus or minus 1 mpg is the closest anyone can get in terms of repeatability and precision.   Even the EPA's $360,000 machine only claims plus or minus 2% of the indicared reading. I can't find where I got the notion that a mom and pop can't possibly get closer than about 4% with a tripmeter/pumpmeter mpg calculation - but I'm still seeking those numbers as we speak.

dpb <none@non.net>: Jul 21 12:42PM -0500 On 07/21/2017 11:51 AM, Mad Roger wrote: ...   > (IMHO) no way to get anywhere near decimal-point accuracy, and worse, > probably plus or minus 1 mpg is the closest anyone can get in terms of > repeatability and precision. ...   Why do errors compound in your view?   And, it depends on what you mean in terms of accuracy -- in terms of absolute one needs to know the calibration error of the odometer; most folks are satisfied to just assume it's close enough for the purpose.   If you look at simply a single fillup, it's not unreasonable to expect a few tenths of a gallon difference between the first fillup level and the subsequent; if you try it on shorter distances than a full tank then the fractional error goes up.   OTOH, if one keeps track over longer periods of multiple fillups and take some care to use the same filling pattern and only fills up after using near the full tank capacity, then over time plus/minus targets _will_ tend to cancel out and I have no qualms in believing a relative performance number in the 0.1 mpg can be determined.   As noted, I've done this on long trips a number of times (generally on first trip or so with a new vehicle, either actually new (rare) or (most often) new to me) just to see how it compared with previous and have had quite good comparisons on recent ones with the computer-computed results. These would be over total distances of 1500 to 2000 miles, not just 20 miles test runs.   --

rickman <gnuarm@gmail.com>: Jul 21 02:02PM -0400 Vic Smith wrote on 7/20/2017 8:29 AM: > So if you want "true" MPG for your car, you have to do it for the life of the car. > Once you do it initially, it's kind of pointless to do again except to satisfy your > curiosity.   +1   I measure my gas mileage on every fillup. I get 19 to 20 MPG every fill unless I do a lot of around town driving. Very consistent. I watch it to see if it drops off which would mean something is wrong.   --   Rick C

Vic Smith <thismailautodeleted@comcast.net>: Jul 21 01:31PM -0500 >indicared reading. I can't find where I got the notion that a mom and pop >can't possibly get closer than about 4% with a tripmeter/pumpmeter mpg >calculation - but I'm still seeking those numbers as we speak.   The EPA doesn't have the time to do accurate MPG numbers Plus/Minus 2% is good enough for the EPA. I'm sure my "mom and pop" MPG number are more accurate than that. But so what? The MPG I get depend on the driving circumstances. For instance, I've measured my MPG on a number of cars on 3000 mile round trips to Florida. I can tell you the EXACT total MPG I got on those 3000 mile trips because I carefully noted the exact metered amount of gas I used, and I verified the odometer accuracy using mile markers. The only real useful thing that gives me is my MPG for the entire trip. That includes local traffic when getting off the highway, and my travels at my destination. But I know my approximate MPG at steady highway speed because I sometimes do tank to tank calculations by filling to the filler tube. That too is an EXACT calculation, but is still only approximate MPG because maybe the terrain and weather may vary. So before you ask about "accurate MPG" you have to define what that is.

Mad Roger <rogermadd@yahoo.com>: Jul 21 07:05PM On Fri, 21 Jul 2017 12:42:08 -0500, dpb wrote:   > Why do errors compound in your view?   It's like a chain is no stronger than the weakest link.   No calculated result can be better than the worse inaccuracy.   > And, it depends on what you mean in terms of accuracy -- in terms of > absolute one needs to know the calibration error of the odometer; most > folks are satisfied to just assume it's close enough for the purpose.   Accuracy, precision, and sigfigs are standard terms: http://www.chem.tamu.edu/class/fyp/mathrev/mr-sigfg.html Accuracy: how closely a measured value agrees with the correct value. Precision: how closely individual measurements agree with each other. Sigfigs: accuracy is no better than the least accurate measurement.   By way of off-the-cuff example, if the accuracy of the odometer is to the billionth of a mile and the accuracy of the pump gallons is to the billionth of a gallon, but the accuracy of the fillup is plus or minus one gallon, then the resulting mathematical (division or multiplication) accuracy can be no better than plus or minus one gallon.   > few tenths of a gallon difference between the first fillup level and the > subsequent; if you try it on shorter distances than a full tank then the > fractional error goes up.   A single fillup will never suffice.   We're trying to compare a MPG *change* between two situations, so, by definition, there _must_ be (at the very least!) /two/ separate calculations. + Calculation before the change (say, smaller tire/wheel diameter) + Calculation after the change (say, larger time/wheel diameter)   > using near the full tank capacity, then over time plus/minus targets > _will_ tend to cancel out and I have no qualms in believing a relative > performance number in the 0.1 mpg can be determined.   That's not necessarily true, because it depends on the understimations balancing out the overestimations, but I'm not going to quibble that more calculations done over time are likely going to randomize the precision and accuracy fluctuations over time.   While I will not quibble with your statement (because I essentially agree with you), I can point out that your speedometer can be consistently wrong in the same direction in either precision or accuracy, in which case it's *not* going to balance out over time. It will be consistently wrong, over time.   But, let's not quibble about that because we both can assume that, for our purposes, the randomization of measurement results will be half the time underestimating and the other half the time overestimating - such that they could balance out.   > quite good comparisons on recent ones with the computer-computed > results. These would be over total distances of 1500 to 2000 miles, not > just 20 miles test runs.   Nobody yet, and even not me, has supported a claim for any better accuracy than my presumed plus or minus one mile per gallon using the standard mom-and-pop test of dividing the number of miles driven based on the tripmeter reading by the pump indication of gallons used to fill back up to a presumed similar previous starting point of amount of fuel consumed.   Remember, the resulting accuracy can't possibly be better than the least accurate measurement.

dpb <none@non.net>: Jul 21 02:20PM -0500 On 07/21/2017 2:05 PM, Mad Roger wrote: ...   > Remember, the resulting accuracy can't possibly be better than the least > accurate measurement.   On a _point_ estimate, yes.   The point I'm making is that it is the _total_ fuel consumed over the total distance; the changes in hitting the target level on a tank-by-tank basis goes away for all excepting the last tank as it doesn't matter in the total. So, if you miss by 0.1 gal on the one tank, yeah, that roughly will translate to 0.1 on the mpg number. But, over the 9 tanks prior to the tenth and last, it doesn't matter; it was all used and so the 0.1 gal error on the last is only a tenth of the size on the overall as it was on the first.   So, over a time, you can get quite precise estimates this way.   As noted, the bias in odometer calibration is a bias, yes, but presuming there's not a reason it is getting worse with time it's not compounding, it just makes a percentage difference in the computed result.   --

Mad Roger <rogermadd@yahoo.com>: Jul 21 09:51PM On Fri, 21 Jul 2017 13:31:01 -0500, Vic Smith wrote:   > calculations by filling to the filler tube. That too is an EXACT calculation, but is still > only approximate MPG because maybe the terrain and weather may vary. > So before you ask about "accurate MPG" you have to define what that is.   We're trying to compare a MPG *change* between two situations: + Calculation before the change (say, smaller tire/wheel diameter) + Calculation after the change (say, larger time/wheel diameter)   If the change itself causes, say, a 1 mpg difference, but if our measurement accuracy is, say, plus or minus 1 mpg, then we'll never see a measurable difference between the two test runs.   Even if we run ten thousand test runs, we'll still never see a statistically valid difference, even though the 1 mpg difference is actually there.   We can't measure any better than our accuracy and repeatability allows.   The factors, I think, are accuracy, precision, repeatability, and, since multiplication/division is involved, each offset worsens the results.   Without answering these questions, nobody, yes, not even you, can say you have an "exact" number, and, I posit, that you can't even get remotely close to exact, using the standard mom-and-pop tripmeter/pumpmeter method.   + Tripmeter accuracy is what in the average car over a 300-mile tank? + Owners ability to "match" the previous level of fuel is what? + Gas station pump reading accuracy is what?

Mad Roger <rogermadd@yahoo.com>: Jul 21 10:05PM On Fri, 21 Jul 2017 14:20:43 -0500, dpb wrote:     > As noted, the bias in odometer calibration is a bias, yes, but presuming > there's not a reason it is getting worse with time it's not compounding, > it just makes a percentage difference in the computed result.   Your multiple-runs argument only holds water for both random accuracy and random precision, but not if one is random and the other is not.   For example, I think it's well known that most speedometers read high *most* of the time (at least that's my understanding - but I could look that up if you question that assertion).   Assuming that assertion is close to correct, let's say they read high by about 5% accuracy most the time (just to make a point), where the precision is about plus or minus 1%.   Notice the accuracy is *always* high while the precision is random around a set point.   http://www.chem.tamu.edu/class/fyp/mathrev/mr-sigfg.html Accuracy: how closely a measured value agrees with the correct value. Precision: how closely individual measurements agree with each other.   If the speedo reads high by 5% all the time, whether you measure your speed once or if you measure your speed a billion times, you'll never any closer to the right speed than 5% plus or minus 1%.   In repeatability, the gauge may give you different figures within + or - 1% of that 5%, which is only to say that the speed will be consistently reading from 4% to 6% higher than the actual speed.   But a billion test runs won't get you any better than that, all of which are at least 4% off from the "correct" measurement (in the example).   My point is that a billion test runs only randomizes that which is random.

root <NoEMail@home.org>: Jul 21 10:25PM > We're trying to compare a MPG *change* between two situations: > + Calculation before the change (say, smaller tire/wheel diameter) > + Calculation after the change (say, larger time/wheel diameter)   Putting different size wheels on the rear will affect the mileage measurement apart from the mpg, so you will have to correct the miles measurement before computing mpg. Smaller wheels => higher miles for the same real distance. You will have to take into account how you drive with the wheel change. If you maintain the same real speed for smaller wheels your engine will be turning over faster than before. Driving at the same speedometer speed with smaller wheels reduces the load on the engine.   As a somewhat off-topic point, manifold vacuum is directly related to instantaneous mpg. It is relatively easy to install a vacuum gauge in the driver's compartment.

rickman <gnuarm@gmail.com>: Jul 21 06:39PM -0400 Ralph Mowery wrote on 7/20/2017 10:57 AM: > last tank full would be where the error would come in. So instead of 1 > gallon of error like the example above, you would have about .1 gallon > of error if the pumps are correct, which they should be.   You obviously don't check your mileage very often. I do and seldom see even 1 MPG difference. I get high 19 or low 20 MPG on 19 out of 20 tanks. I think the idea of uneven filling of the tank is a red herring. I can't remember the last time I saw a gas station on a slope.   Bottom line is try it and see. I expect the major factor in MPG variation is actual MPG variation from driving a different mix of town and highway driving.   --   Rick C

dpb <none@non.net>: Jul 21 06:05PM -0500 On 07/21/2017 5:05 PM, Mad Roger wrote: ...   > But a billion test runs won't get you any better than that, all of which > are at least 4% off from the "correct" measurement (in the example).   > My point is that a billion test runs only randomizes that which is random.     We'd already thrown the mileage calibration bias out as being simply that. It can be compensated for by comparison over set measured course and recording the offset. Red herring for the discussion.   The point I'm making is that it doesn't matter at all about whether there's any random error in the fillup on individual tanks at all on the intermediary answers--yes, they may have some fluctuation owing to inconsistent fillup, but one can assume the pump is accurate since they're checked by the State weights and measures folks on a regular basis. So, all the fuel that went in went out in accumulating the miles and it didn't matter how much went in on each individual measurement at all in the end--it's the total. Only that random error on the final fillup when you make the calculation at the end does that error enter in -- and it becomes quite small by then in comparison to the total.   And, if one computes the mean of the billion trials, the error in the mean is quite small even if the random error in each trial is sizable.   --

Mad Roger <rogermadd@yahoo.com>: Jul 21 11:13PM On Fri, 21 Jul 2017 18:39:37 -0400, rickman wrote:   > 1 MPG difference. I get high 19 or low 20 MPG on 19 out of 20 tanks. I > think the idea of uneven filling of the tank is a red herring. I can't > remember the last time I saw a gas station on a slope.   I don't think I've ever seen a gas station on a slope. However ... The errors in the calculation stem from errors that nobody seems to know what they are, which means nobody knows what they're talking about.   Assuming the tripmeter/pumpmeter calcultion is the method used, + A tripmeter of 300 miles is neither accurate nor precise + A pumpmeter of 20.25 gallons is likely relatively accurate & precise + Matching fuel level in the tank isn't even close to accurate nor precise   Any one measurement (either miles or gallons alone) can only be as accurate and precise as the worst measurement, while the miles/gallons calculation compounds those inaccuracies and imprecisions (in loss of sig figs).   I think most of us would probably assume the pumpmeter is the most accurate and the most precise, but the other two measurements aren't even close to accurate or precise.   What matters is how accurate & precise is a 300 mile tripmeter reading? And how accurate and precise is the match to the previous fuel level?   I posit that the best you can do, overall, after running the calculation, is something like plus or minus about 1 mile per gallon such that 20 mpg is actually anywhere from 19 to 21 miles per gallon actual.   What I'm seeking is data that tells us the three main questions that must be answered for anyone to say that my hypothesis is even close to being right or wrong:   + How accurate & precise is a reading of 300 miles on a typical tripmeter? + How accurate & precise is a reading of 20.25 gallons on a gas pump? + How accurate & precise is the matching of the prior fuel level done?   No calculation can do better than the worst measurement, and worse, errors compound when you multiply or divide.   > Bottom line is try it and see. I expect the major factor in MPG variation > is actual MPG variation from driving a different mix of town and highway > driving.   But that's the kind of things we're looking for, which is why the minimum number of calculations possible is two, since you have to have a "before" situation and an "after" situation.   For example, if the change that you are testing causes about 1 mile per gallon decrease in fuel economy overall (but which isn't linear), but if your calculations are no better than plus or minus 1 mile per gallon in accuracy or precision, then you'll never even see the very real difference because it will be unmeasurable given the plus or minus 1 mile per gallon typical accuracy and precision that I posit the typical mom-and-pop tripmeter/pumpmeter calculation provides.   But there's no sense in talking about *any* of that, if we don't know the answer to these three questions. + How accurate & precise is a reading of 300 miles on a typical tripmeter? + How accurate & precise is a reading of 20.25 gallons on a gas pump? + How accurate & precise is the matching of the prior fuel level?

Mad Roger <rogermadd@yahoo.com>: Jul 21 11:13PM On Fri, 21 Jul 2017 18:39:37 -0400, rickman wrote:   > 1 MPG difference. I get high 19 or low 20 MPG on 19 out of 20 tanks. I > think the idea of uneven filling of the tank is a red herring. I can't > remember the last time I saw a gas station on a slope.   I don't think I've ever seen a gas station on a slope. However ... The errors in the calculation stem from errors that nobody seems to know what they are, which means nobody knows what they're talking about.   Assuming the tripmeter/pumpmeter calcultion is the method used, + A tripmeter of 300 miles is neither accurate nor precise + A pumpmeter of 20.25 gallons is likely relatively accurate & precise + Matching fuel level in the tank isn't even close to accurate nor precise   Any one measurement (either miles or gallons alone) can only be as accurate and precise as the worst measurement, while the miles/gallons calculation compounds those inaccuracies and imprecisions (in loss of sig figs).   I think most of us would probably assume the pumpmeter is the most accurate and the most precise, but the other two measurements aren't even close to accurate or precise.   What matters is how accurate & precise is a 300 mile tripmeter reading? And how accurate and precise is the match to the previous fuel level?   I posit that the best you can do, overall, after running the calculation, is something like plus or minus about 1 mile per gallon such that 20 mpg is actually anywhere from 19 to 21 miles per gallon actual.   What I'm seeking is data that tells us the three main questions that must be answered for anyone to say that my hypothesis is even close to being right or wrong:   + How accurate & precise is a reading of 300 miles on a typical tripmeter? + How accurate & precise is a reading of 20.25 gallons on a gas pump? + How accurate & precise is the matching of the prior fuel level done?   No calculation can do better than the worst measurement, and worse, errors compound when you multiply or divide.   > Bottom line is try it and see. I expect the major factor in MPG variation > is actual MPG variation from driving a different mix of town and highway > driving.   But that's the kind of things we're looking for, which is why the minimum number of calculations possible is two, since you have to have a "before" situation and an "after" situation.   For example, if the change that you are testing causes about 1 mile per gallon decrease in fuel economy overall (but which isn't linear), but if your calculations are no better than plus or minus 1 mile per gallon in accuracy or precision, then you'll never even see the very real difference because it will be unmeasurable given the plus or minus 1 mile per gallon typical accuracy and precision that I posit the typical mom-and-pop tripmeter/pumpmeter calculation provides.   But there's no sense in talking about *any* of that, if we don't know the answer to these three questions. + How accurate & precise is a reading of 300 miles on a typical tripmeter? + How accurate & precise is a reading of 20.25 gallons on a gas pump? + How accurate & precise is the matching of the prior fuel level?

Vic Smith <thismailautodeleted@comcast.net>: Jul 21 06:22PM -0500 >If the change itself causes, say, a 1 mpg difference, but if our >measurement accuracy is, say, plus or minus 1 mpg, then we'll never see a >measurable difference between the two test runs.   Under just moderately controlled conditions, 1 MPG is actually a significant amount, and would be easily detectable using your mom and pop method, assuming the mom and pop competently applied the method.     >+ Tripmeter accuracy is what in the average car over a 300-mile tank? >+ Owners ability to "match" the previous level of fuel is what? >+ Gas station pump reading accuracy is what?   I never used the tripmeter for MPG, because I never bothered testing them with mile markers. Matching gas level is trivial - and it only has to done at the beginning and end of the trip. Gas station pumps - I assume they are accurate, and can't control that anyway. I'm confident that my measurements are accurate to within .1 MPG. Because I don't care about .135867 on the total. I round it down to .1 That's pretty "exact." Repeatability is meaningless when measuring MPG, unless you're driving on a covered track, with a temperature controlled environment. On every trip the MPG can vary. BTW, I don't disagree that perfect measurement of MPG in unattainable. Perfection is impossible even under lab conditions. But you too easily discount "mom and pop" MPG calculations.

Mad Roger <rogermadd@yahoo.com>: Jul 21 11:30PM On Fri, 21 Jul 2017 18:05:52 -0500, dpb wrote:   > We'd already thrown the mileage calibration bias out as being simply > that. It can be compensated for by comparison over set measured course > and recording the offset.   I agree with you that the tripmeter calculation is inaccurate to some degree, for which there are ways of "calibrating" the equipment.   > Red herring for the discussion.   The answer to the question depends on only 3 factors, I think.   Given these three factors are critical to answer the question, I think everyone is talking out of their ass (including me) if they can't answer these three questions to validate their own thought process:   + How accurate & precise is a reading of 300 miles on a your tripmeter? + How accurate & precise is a reading of 20.25 gallons on the gas pump? + How accurate & precise is the matching of the prior fuel level?   I posit both the tripmeter and the previous-fill-level measurements suck. How much to they suck?   I don't know.   I would not be surprised if they suck so badly that the end result is a calculation which is plus or minus 1 mile per gallon in either accuracy or repeatability.   > inconsistent fillup, but one can assume the pump is accurate since > they're checked by the State weights and measures folks on a regular > basis.   While it will be useful to know what the accuracy and precision (repeatability) of the pump is, I think we can all assume that the pump is within something like (at least) plus or minus a few percent of what it reads.   But that number can be accurate to a billionth of a gallon, and it still would be meaningless if the fill level was off by plus or minus a gallon because the accuracy of any one measurement is only as good as the worst measurement and the accuracy of the final calculation (when multiplication adn division are involved) compounds inaccuracies.   Anyway, all the words are moot if we don't know the answer to 3 questions: + How accurate & precise is a reading of 300 miles on a your tripmeter? + How accurate & precise is a reading of 20.25 gallons on the gas pump? + How accurate & precise is the matching of the prior fuel level?   > all in the end--it's the total. Only that random error on the final > fillup when you make the calculation at the end does that error enter in > -- and it becomes quite small by then in comparison to the total.   Am I correct to understand that you are saying if you go only 300 miles on one tank, then the fill-level inaccuracy is (say) plus or minus 1 gallon per tank; but if you go 3,000 miles (obviously on multiple tanks), that the fill-level inaccuracy is one tenth of that plus or minus one gallon per tank?   > And, if one computes the mean of the billion trials, the error in the > mean is quite small even if the random error in each trial is sizable.   As long as the error is random (i.e., in both directions of the true answer).

Mad Roger <rogermadd@yahoo.com>: Jul 21 11:35PM On Fri, 21 Jul 2017 18:22:08 -0500, Vic Smith wrote:   > I'm confident that my measurements are accurate to within .1 MPG.   Assuming one tank is about 300 miles and about 20.25 gallons read on any one pump, on a long trip of ten times that, you still can't be confident of that 1/10th of a mpg unless you know the answer to these questions.   + How accurate & precise is the combined reading of 3000 miles on your tripmeter? + How accurate & precise is the combined reading of 202.50 gallons on the 10 gas pumps? + How accurate & precise is the matching of the 1st & last fuel levels?   Remember the exammple of the speedometer, where it's *always* going to be a few percent wrong, even if you drove a billion miles to try to "randomize" out the errors.

jurb6006@gmail.com: Jul 21 03:37PM -0700 On Wednesday, July 19, 2017 at 4:53:41 PM UTC-5, John-Del wrote:   > > Its one or the other - delta is a bundle of guns and inline is exactly what > > it says.   > Yep, misspoke. The porta-color used an inline gun but retained the round RCA style shadow mask. When viewed up close, the round phoshpors looked a lot like the earlier delta. Later in-lines (including the Trini) used the rectangular slots that were quite obvious even when the TV was off.   It is totally possible to use inline guns with a triad type shadow mask. In fact it holds its shape better than the slit type mask. Plus, with such poor resolution (screen pitch) it looked better.   Those GEs with the AA and AB chassis' were not something I was in love with to say the least. Had to resolder all those feedthroughs. Plus they used a wafer tuner which is harder to clean properly.   I did make some money fixing them but you can't charge that much on those elcheapo sets.   Actually though, it was very rare that I had to replace any parts in them.

GattoNero <miao@miao.it>: Jul 21 11:49PM +0200 > Have you gone to the Horse's Mouth? At the very least, you might be able to get a schematic.   mmm really, sir, my english knowledge is not so good to appreciate if this is a sarcastic phrase or some coloured way of saying somethings... Can you explain better what are you talking about?     > https://www3.fronius.com/cps/rde/xchg/SID-12218796-57DE8E7D/fronius_usa/hs.xsl/3022_3755.htm#.WXDn3oTyvIV   Thanks sir...I've just told you that the official assistance said that no repair is possible due to no more spare parts....Maybe contacting an USA service is different but I don't think so...     > Generally, I do not take "my friend said..." as the epitome of exhaustive research.   Bho...Maybe sometimes is only question of kind of friends...   Diego -Italy-

Michael Black <et472@ncf.ca>: Jul 21 01:42PM -0400

William Unruh <unruh@invalid.ca>: Jul 21 07:05PM >>> browser ID to see what it looks like?   >> FYI, there is a Ubuntu newsgroup: alt.os.linux.ubuntu   > Thanks for the admonition that there is a ubuntu-specific ng.   I am virtually certain that there is nothing special about ubuntu in any of this. tools available on Ubuntu are also there on other versions of Linux. This is about opera (which operates on all versions of linux).     > parameters perhaps) and where the ID is stored (so that we may look at it > perhaps) & in what form do you think it's transmitted & to whom (so that we > may watch and intercept it perhaps)?   This is not a question in which wild guesses are going to be of much use.   IF you know where the uniqID is sent to you could use tcpdump with that IP as the host. But since we have no idea where it is sent to, that is probably pointless.     You have the source for Opera, and you could look through that to find if there are any indicators to "unique ID"

"Ian Field" <gangprobing.alien1@virginmedia.com>: Jul 21 06:42PM +0100 Some of the HDDs were rescued from binned cable PVRs, all were Seagate - so it was no surprise when a few started clicking and tangling up FAT chains.   Since taking out the old PC and firing up a spare, most of the drives are behaving now, a couple started with the blue screen of CHKDSK during boot but seemed fine after that. One failed to detect and still does on the new PC, another prevented boot but was recoverable on the new PC.   Any tips on narrowing down the exact cause?   PSU ripple could be it - but I only have a basic load tester.   Thanks for any help.   PS: Drives were also getting jangled on a JMJ raid card I was using unconfigured to get more USB sockets.

"Ian Field" <gangprobing.alien1@virginmedia.com>: Jul 21 06:58PM +0100 "Ian Field" <gangprobing.alien1@virginmedia.com> wrote in message news:R1rcB.450228$h63.63378@fx34.am4...   > Thanks for any help.   > PS: Drives were also getting jangled on a JMJ raid card I was using > unconfigured to get more USB sockets.   Typo - that was supposed to be SATA sockets.

Robert Roland <fake@ddress.no>: Jul 21 07:47PM +0200 On Fri, 21 Jul 2017 15:21:22 +0100, Arfa Daily   >removing the type of clip that needs expanding, but has just a pair of >sort of 'opposite-facing "C"s' on the ends of the arms,   I have been searching for that a wile as well. It seems they are called flat nose snap ring pliers or flat nose retaining ring pliers. I have not found any cheap ones, though.   >thing that I could suggest to him was that he take a pair of 'tradional' >pin-tip ones, and Dremel a slot in each pin with a diamond cutting wheel >like I keep in mine most of the time for jobs like this.   That's what I did. I used an angle grinder to remove some material from the inside of the jaws, so that they close a little tighter. On the outside, I simply used a bench grinder. I have left the surface plain flat for now. I have used it only once, but it worked fine. -- RoRo

Arfa Daily <arfa.daily@ntlworld.com>: Jul 21 06:49PM +0100 On 21/07/2017 15:55, Ken Layton wrote:   > Sears has several more styles of snap ring pliers:   > http://www.sears.com/search=snap%20ring%20pliers   > Some are for both internal and external style snap rings while others are for internal only or external only.   Have you actually used yours on the type of clip that I was trying to describe - i.e. without actual holes in the arms ? My colleague was trying to use some that look pretty similar to those that you linked to, but they just slipped, even though they were an appropriate size   Arfa

N_Cook <diverse@tcp.co.uk>: Jul 21 06:51PM +0100 On 21/07/2017 15:21, Arfa Daily wrote: > of clip or if the clip or tool has a unique name rather than it just > being a variant of an 'external circlip' ?   > Arfa   Usually the C ends are quite close together. I just grab a range of jewellers flat blade screwdrivers and find one that inserts at an angle and when twisted , opens out the arms, the circlip laying nicely on the blade..

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