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N_Cook <diverse@tcp.co.uk>: Apr 14 01:23PM +0100 Please excuse the horological terms in the following. A nice brass and glass dome Horolovar type 400-day , at least 50 year old J Haller of Germany, torsion suspension clock. I've reset the pallets on the escapement so it is back in working order. These clocks are notorious for bad time keeping, bu tlook great, as no fusee or remontoire mechanism so the back torque from the main spring varies fully from fully wound to near unwound. Rotation escapement is 8 turns per minute or 7.5 seconds per cycle, exactly , in theory, but impossible to maintain even over a week let alone a year, summer and winter etc. Playing with a very basic 1.5V plastic quartz-timed clock mechanism with balance wheel escapement, about 0.8mA pulse every 3 seconds powering its escapement via a solenoid. If I brought out the solenoid to the steel "metronome" arm part of the escapement on this clock, any chance of it keeping time? Main motive power would still be the clockwork. So a pulse at end of swing at 0 seconds, pulses at 3,6,9,12 miss altogether, leaving just pulse at 15 seconds, so 4 per minute. If the arm arrives late the pulse pulling it closer and if the arm leaves early it is pulled back slightly, or am I missing something fundamental. Hopefully around the 7.5 second full cycle one, it would be too distant to be influenced by pulses at 6 or 9. Or would an astronomic type gravitational lock situation arise , with drift , and another synchronism would emerge?

"pfjw@aol.com" <peterwieck33@gmail.com>: Apr 14 05:47AM -0700 a) These clocks were never meant to keep time. They were meant to be ornamental. b) These clocks, generally, were the toys of the wealthy. They had servants to (discreetly) reset the clock each morning. c) Any such clock modified to keep time would be anathema. To the clock and to the hobby.   Get it to run reasonably reliably, and then have Throckmorton set it each morning such that you believe it to be keeping time.   Peter Wieck Melrose Park, PA

N_Cook <diverse@tcp.co.uk>: Apr 14 02:23PM +0100 > Get it to run reasonably reliably, and then have Throckmorton set it each morning such that you believe it to be keeping time.   > Peter Wieck > Melrose Park, PA   Scrotum is too occupied ironing The Telegraph for me, to accommodate that extra chore.

Mike Coon <gravity@mjcoon.plus.com>: Apr 14 03:59PM +0100 In article <pasvcb$3gn$1@dont-email.me>, diverse@tcp.co.uk says... > > Melrose Park, PA   > Scrotum is too occupied ironing The Telegraph for me, to accommodate > that extra chore.   Have it done at night. It must be just the cumulative error that is to be eliminated. Only the working class are going to worry about absolute error...   Mike.

jurb6006@gmail.com: Apr 14 01:18AM -0700 <"I've heard of Jeff - never heard of you. From what I've read so far, you will never know a tenth of what Jeff does (and I suspect I'm being generous). Further, he's not "snit".. "   If so, he hides it well. And the fact remains that even if he is a genius he has the mentality of a child. Not that we've seen evidence of any genus.   And heard of ? I heard of plenty of people. Like the guy who set his motor home to cruise control and then sued because he thought it would drive itself and went in the back leaving the driver's seat empty. He was genius enough to impel manufacturers to put a warning in the motor homes to the effect that you have to drive them.   It is surprising that the guy could afford a motor home being that fucking stupid but he could.   Heard of. Yeah.

Fox's Mercantile <jdangus@att.net>: Apr 14 06:03AM -0500 On 4/14/18 3:18 AM, jurb6006@gmail.com wrote: [ yap yap yap ]   Somebody let him outside before he pisses on the carpet. Again.     -- "I am a river to my people." Jeff-1.0 WA6FWi http:foxsmercantile.com

"pfjw@aol.com" <peterwieck33@gmail.com>: Apr 13 10:07AM -0700 On Friday, April 13, 2018 at 12:13:21 PM UTC-4, Jeff Liebermann wrote: Should that happen, be advised > that I derive considerable sadistic enjoyment watching others reinvent > the wheel.   Oh, you should, you should!   Horses for courses. Special applications require special attention - no surprise there.   Generally, when I "fix" something, I want it to stay that way. So, I will use (where appropriate) precision resistors, 105C+ caps, pre-screened film caps, matched transistors, dual-element fuses - again, where appropriate. The incremental cost across any one device will be less than the postage for that 'special' part and so forth. And, I also want to understand the 'why' of things. But I have no particular investment in being 'right', or even in being 'correct'. Just in the ultimate results.   Case-in-point - the relay for the HK Citation 17. After all the discussion, using the OEM relay just turned out to give a good result with no second thoughts or guesses. Good enough for me. Was it my only good option? Probably not. Was it -a- good option. Yes.   Peter Wieck Melrose Park, PA

whit3rd <whit3rd@gmail.com>: Apr 13 03:57PM -0700 > When mounting power transistors and chips to a heat sink they often use > heat shrink grease   That greasy stuff (also available in waxy and rubbery forms) is thermal transfer compound; like a grease, but it is NOT grease.   It has to stay put in small crevices in order to work.   If you use a 'grease' formula instead of a 'thermal compound' formula, it might only work for a few hours, then flow away.   If you try to add particles with high thermal conductivity to grease, you might just be making spacers to keep the metal parts at a distance (it's distance times resistance-to-heat-trasfer that you want to minimize). Don't fall for the 'better conductivity' argument, it's conductivity DIVIDED BY GAP DISTANCE you care about.

Jeff Liebermann <jeffl@cruzio.com>: Apr 13 04:06PM -0700 On Fri, 13 Apr 2018 10:07:46 -0700 (PDT), "pfjw@aol.com" >> that I derive considerable sadistic enjoyment watching others reinvent >> the wheel.   >Oh, you should, you should!   I do, I do. I positively salivate at the possibility of telling the experts "I told you so".   >Generally, when I "fix" something, I want it to stay that way.   Sure, if I can get the right parts. More commonly, I have a schedule to meet and am forced to use not so wonderful parts. Using substitute or recycled parts has caused me grief a few times, but in general, it works because I understand how the circuit works and therefore what I can get away with doing.   Incidentally, you can get diamond doped thermal goo: <https://www.innovationcooling.com/products/ic-diamond/> Not too expensive for those who want the very best at any price: <https://www.newegg.com/Product/ProductList.aspx?Submit=ENE&DEPA=0&Order=BESTMATCH&Description=ic+diamond>   >I also want to understand the 'why' of things.   Yep. If you re-read my long and boring rants on proper abuse of thermal goo, you might notice that I spent quite a few bytes explaining how things worked and why I do things in some particular manner. While I believe that everyone is entitled to expressing their opinions, I usually ignore the one-line "conversations" that have become the defacto standard of chat type communications. Without substantiation and explanation, opinions are worthless.   >But I have no particular investment in being 'right', or even in >being 'correct'. Just in the ultimate resuts.   I have an investment in being (mostly) right. I value my reputation, or at least what's left of it after making a few major screwups. If "ultimate results" means doing whatever it takes to separate the customer from their money, we need to have discussion on ethics.         -- Jeff Liebermann jeffl@cruzio.com 150 Felker St #D http://www.LearnByDestroying.com Santa Cruz CA 95060 http://802.11junk.com Skype: JeffLiebermann AE6KS 831-336-2558

dplatt@coop.radagast.org (Dave Platt): Apr 13 05:25PM -0700 >>"but you are supposed to mix it 50-50. They claim that 100% antifreeze can freeze."   >Whoever claimed that is an idiot. Don't listen to them. Actually anytihng can freeze, but that is not what they meant. The statement indicates they're totally >unfamiliar with chemistry and physics.   I see a whole bunch of charts on the net, which show the freezing temperature of various glycol-and-water mixtures.   For ethylene glycol, there's a very clear eutectic effect taking place. The freezing point decreases from 0C to -50C, as the concentration of EG in in the mix increases from 0% to about 65%. At ratios above that (more than 65% EG, less than 35% water), the mixture freezes at increasingly _higher_ temperatures. The freezing point of 100% ethylene glycol is shown as being around -20C, or not much "below zero" Farenheit.   The curve for propylene glycol is very different. A mixture of PG and water freezes at a few degress higher than an equivalent EG/water mix, up to that magic 65% ratio... but the freezing point continues to drop (slowly) all the way up to 100% PG. There's no visible eutectic effect that I can see. However, the rate-of-decrease is quite low above about 70% - going all the way up to 100% PG gains you only a couple of degrees of increased freeze protection.   So, the question of "what's the right mix of antifreeze and water, for the best freeze protection" depends very much on *WHICH* glycol is in the antifreeze. I suspect a mixture of the two may have a more complex behavior.   If you're starting with a 100% (or close to it) ethylene glycol antifreeze, then the advice to stick to 50:50 looks very good, as far as freeze protection is concerned. If you go up to straight 100% glycol, you're good down to around -10F or -20C, but below that, the glycol *will* freeze. You'd save money and have significantly better freeze protection with 60:40 or 70:30.   If you're using propylene glycol, loading up to 80% or more won't hurt your freeze protection... but it's still not as good protection as you'd get with a 60:40 or 70:30 EG mixture.   >As for antifreeze, if there is no water at all in there it is much less likely to form corrosive components. There is a difference in how it cools though, thus :   Keeping it absolutely dry is going to be difficult in practice. It's going to absorb at least some moisture via the reserve tank, I imagine.

Jeff Liebermann <jeffl@cruzio.com>: Apr 13 07:59PM -0700 On Fri, 13 Apr 2018 16:06:03 -0700, Jeff Liebermann <jeffl@cruzio.com> wrote:   ><https://www.innovationcooling.com/products/ic-diamond/> >Not too expensive for those who want the very best at any price: ><https://www.newegg.com/Product/ProductList.aspx?Submit=ENE&DEPA=0&Order=BESTMATCH&Description=ic+diamond>   Thermal Paste Application Methods - Which one is best? - The Workshop <https://www.youtube.com/watch?v=r2MEAnZ3swQ> (10:13) Included are various lines, an X, a P, finger smear, too much, too little, etc. If you're impatient, skip to 7:49 for a Powerpoint chart with the results.   -- Jeff Liebermann jeffl@cruzio.com 150 Felker St #D http://www.LearnByDestroying.com Santa Cruz CA 95060 http://802.11junk.com Skype: JeffLiebermann AE6KS 831-336-2558

"pfjw@aol.com" <peterwieck33@gmail.com>: Apr 14 03:38AM -0700 On Friday, April 13, 2018 at 7:06:19 PM UTC-4, Jeff Liebermann wrote:   > or at least what's left of it after making a few major screwups. If > "ultimate results" means doing whatever it takes to separate the > customer from their money, we need to have discussion on ethics.   This is a hobby, not a business. I have yet to take any sort of compensation for anything other than parts for any repair (for a friend) I have ever made. As I do not make repairs for strangers, that is moot. I want the device to be safe, functional and reliable once it leaves my bench. Full Stop.   Peter Wieck Melrose Park, PA

Ralph Mowery <rmowery28146@earthlink.net>: Apr 13 01:06PM -0400 In article <2f65767f-2974-4182-b25b-15888a6eca13@googlegroups.com>, timothy42b@aol.com says...   > If we have two LEDs in parallel in reversed polarity, and we put 12 volts across them, aren't we exceeding both Vf and Vr? will they share the current, at some calculable ratio?   > Sorry for my ignorance, that electrical circuits class was in the 80s.   LEDs do not really have a voltage rating as such. They are current devices. You just have to limit the current to a safe level. That is why there is almost always a resistor in series.   For many circuits you can forget the voltage of the led and just figuer the resistance value dependin on the current your led will need for the brightness you want. If very low voltage circuits, say under 12 volts, substract the 1 to 3 volts the led is rated at from the supply voltage.   The LED will have a voltage across it of about 1 to 3 volts depending on the type in the forward direction. That voltage is almost the same no matter what the current is within reason.

Tim R <timothy42b@aol.com>: Apr 13 10:47AM -0700 On Friday, April 13, 2018 at 1:06:30 PM UTC-4, Ralph Mowery wrote: > LEDs do not really have a voltage rating as such. They are current > devices. You just have to limit the current to a safe level.   Okay. 12 volt car battery, 1k resistor, the most current you can get is 12 mA, any LED should handle that. But that's not the fault condition I was wondering idly about.       > The LED will have a voltage across it of about 1 to 3 volts depending on > the type in the forward direction. That voltage is almost the same no > matter what the current is within reason.   My first thought is if he used one LED and connected it backwards, he could think a circuit was dead that was really hot, and burn up his new red sports car. Or he'd always have to fuss with getting the right lead on. I didn't realize he had a ground clamp and probe, so I was probably just wrong on this one. I was thinking two probes.   My second thought was if he uses 2 LEDs in parallel, and they're both above 5 volts, then they're both conducting. How much current goes through the forward biased one? enough to give a bright light, or maybe dim enough he thinks the circuit is dead and he burns up his new red sports car.

tabbypurr@gmail.com: Apr 13 11:31AM -0700 On Friday, 13 April 2018 18:48:02 UTC+1, Tim R wrote: > > matter what the current is within reason.   > My first thought is if he used one LED and connected it backwards, he could think a circuit was dead that was really hot, and burn up his new red sports car. Or he'd always have to fuss with getting the right lead on. I didn't realize he had a ground clamp and probe, so I was probably just wrong on this one. I was thinking two probes.   > My second thought was if he uses 2 LEDs in parallel, and they're both above 5 volts, then they're both conducting. How much current goes through the forward biased one? enough to give a bright light, or maybe dim enough he thinks the circuit is dead and he burns up his new red sports car.   someone is not familiar with LEDs

Ralph Mowery <rmowery28146@earthlink.net>: Apr 13 04:49PM -0400 In article <6fc822f2-5067-4617-a903-107399f6912e@googlegroups.com>, timothy42b@aol.com says...   > My second thought was if he uses 2 LEDs in parallel, and they're both above 5 volts, then they're both conducting. How much current goes through the forward biased one? enough to give a bright light, or maybe dim enough he thinks the circuit is dead and he burns up his new red sports car.   You put them so one diodes anode is connected to the cathode of the other. Only one will lite at a time on DC.   Best little handy dandy checker I ever had is one made by Fluke. I think it is a T2. Has about 10 or 12 LEDs in it and 2 leads. You just hook the leads to anything you want to check. If open, nothing hapens. if low resistance it beeps and a led lights up. Anything over about 3 volts DC and it gives an indication of power and direction. Good to about 200 or 250 volts dc. When used on ac, it starts somewhat higher and goes to atleast 600 volts. The leds inbetween nothing and mix give a rough indication of more common voltges such as 120,220 480 and 600 volts AC. It starts at 6, 12, 24 and I forget the others for DC.

whit3rd <whit3rd@gmail.com>: Apr 14 01:42AM -0700 On Thursday, April 12, 2018 at 8:19:07 AM UTC-7, Terry Schwartz wrote: > That can easily be addressed by using two LEDs in parallel, in opposite polarity.   > > At the risk of pointing out the obvious, an incandescent bulb doesn't care which end is positive. An LED on the other hand..................   One variant is to get a bicolor LED; these are usually red forward, green reverse biased. It's better not to tease the R/G colorblind population, though, and a white LED pair, behind + and - shaped windows, would be a better indicator.

Fox's Mercantile <jdangus@att.net>: Apr 13 02:14PM -0500 On 3/12/18 9:19 AM, Fox's Mercantile wrote: > And because I'm a stubborn bastard, I made a Cisco 7912 VoIP > phone work with the system as well. So I can have a phone at > the shop.   It gets better, I have 6 of them now AND a VoIP phone line as well.   -- "I am a river to my people." Jeff-1.0 WA6FWi http:foxsmercantile.com

N_Cook <diverse@tcp.co.uk>: Apr 13 07:37PM +0100 > That is so cool. I had no idea that was how the eggs got that look. > Thanks for posting. > Eric   If it was anyone else other than Attenborough saying that, I'd have disbelieved them. I've never seen an egg with streaks on it, so difficult to believe that mechanism.

Mike Coon <gravity@mjcoon.plus.com>: Apr 13 05:56PM +0100 In article <MPG.3535a6739f60412c98977f@news.east.earthlink.net>, rmowery28146@earthlink.net says...   > One give away for me is to take the heat gun of my hot air rework > station and playing it around one or two capacitors at a time. If the > set starts working or manking a big change I replace them.   The heat gun I have is a paint stripper. I use it a lot to shrink heat- shrink tubing but am reluctant to play it on electronics. And I cannot find the non-contact thermometer I was sure I had.   Viewing the youtube video I think was meant, I see the same capacitors have bulges in my power supply. So though I cannot pop down to my local Maplin (like the youtuber) because they have since gone out of business, I have ordered replacements, fitted three, and the monitor is now working!   It is sad that a board clearly marked 2007 already has multiple duff components (assuming they are duff). I notice that the bulgy capacitors have cross-scores on the flat end, almost like a hot-cross bun. The scores recall a burst diaphragm, so I wonder if they are a safety feature for components which are considered quite likely to fail explosively! The words written on the items include "VENT", which makes me think that I might be right...   As well as three bulging capacitors there are three flat-ended ones which are also scored, so I hope those are "good".   I do not have an ESR meter but have noticed many discussions of such in this NG over the years...   Thanks to all respondents.   Mike.

tabbypurr@gmail.com: Apr 13 10:14AM -0700 On Friday, 13 April 2018 17:56:05 UTC+1, Mike Coon wrote:   > this NG over the years...   > Thanks to all respondents.   > Mike.   Lytics can explode if no such precautions are taken during mfr     NT

Ralph Mowery <rmowery28146@earthlink.net>: Apr 13 01:21PM -0400 In article <MPG.353af18286183a7e9896a3@news.plus.net>, gravity@mjcoon.plus.com says... > feature for components which are considered quite likely to fail > explosively! The words written on the items include "VENT", which makes > me think that I might be right...   Glad you got the monitor going. Seems that many of the simple repairs are just replacing the capacitors around a switching power supply. For some reason the switchers seem very hard on capcitors. They build up heat and will vent the steam. Most electrolytic capacitors are not really dry inside, but slightly moist. When the heat builds up and th epressure is too much, they burst. That could be the reason for the scores on the capacitors, not sure. They will have a way of bursting and venting the steam with a large explosion for the most part.     If possiable you should look at the temperature ratings of the capacitors. Some are around 80 deg C and some are around 100 or more. Always get the highest temperature ratings you can.

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