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John-Del <ohger1s@gmail.com>: Apr 14 01:42PM -0700 I have this device which uses 14 AA rechageable batteries. It was originally shipped from the factory with nicds and a charger.   The instructions show it has two recharge modes switchable from the front panel; recharge and store. The store is a very low trickle charge. Because it's from the early 80s, I'm assuming it's just a current limited charger (dumb charge) as it takes 14 hours to charge the entire group.   I would have like to install eneloops in it, but anecdotal evidence suggests they don't like this type of charge, so I'm back at looking at regular nicads for it.   So, is it true that Panasonic eneloop cells need a smart charger and does anyone know if anyone is making a quality nicad battery anymore? In the old days, I'd buy Sanyo nicads and although they'd often advertise less mah per cell than others, they seemed to last almost forever.

tabbypurr@gmail.com: Apr 14 06:29PM -0700 On Saturday, 14 April 2018 21:42:30 UTC+1, John-Del wrote:     > The instructions show it has two recharge modes switchable from the front panel; recharge and store. The store is a very low trickle charge. Because it's from the early 80s, I'm assuming it's just a current limited charger (dumb charge) as it takes 14 hours to charge the entire group.   > I would have like to install eneloops in it, but anecdotal evidence suggests they don't like this type of charge, so I'm back at looking at regular nicads for it.   > So, is it true that Panasonic eneloop cells need a smart charger and does anyone know if anyone is making a quality nicad battery anymore? In the old days, I'd buy Sanyo nicads and although they'd often advertise less mah per cell than others, they seemed to last almost forever.   Over here they're banned now. FWIW I had good results years ago with very old nicads, but yeah, the capacity isn't hot.   I also wouldn't ignore the possibility of just using cheap new NiMH, if the capacity is enough.     NT

mike <ham789@netzero.net>: Apr 14 06:56PM -0700 On 4/14/2018 1:42 PM, John-Del wrote:   > The instructions show it has two recharge modes switchable from the front panel; recharge and store. The store is a very low trickle charge. Because it's from the early 80s, I'm assuming it's just a current limited charger (dumb charge) as it takes 14 hours to charge the entire group.   > I would have like to install eneloops in it, but anecdotal evidence suggests they don't like this type of charge, so I'm back at looking at regular nicads for it.   > So, is it true that Panasonic eneloop cells need a smart charger and does anyone know if anyone is making a quality nicad battery anymore? In the old days, I'd buy Sanyo nicads and although they'd often advertise less mah per cell than others, they seemed to last almost forever.   There are a LOT of variables here. It would be helpful to know what it is. Are the batteries in series, parallel, separate supplies? Is the OFF power drain really zero? Is it gonna sit for a long time between uses?   '80's nicads were probably about 500maH. With eneloops, that 14 hour charge might become 56 hours. If there are 14 cells in series, there's a lot of opportunity to have at least one cell reversed by the time you sense any symptoms. Keep doing that and you'll kill 'em all eventually.   The best strategy is to charge the cells externally in a proper charger and put 'em back in when you're ready to use it.   There are many charging strategies, but depend heavily on the usage patterns and actual cell configurations.

Jeff Liebermann <jeffl@cruzio.com>: Apr 14 07:18PM -0700 On Sat, 14 Apr 2018 13:42:27 -0700 (PDT), John-Del <ohger1s@gmail.com> wrote:   >I have this device which uses 14 AA rechageable batteries.   There's quite a bit on charging Eneloop cells here: <https://eneloop101.com> <https://eneloop101.com/charge/> Plenty of warnings to NOT use really fast chargers and really dumb (trickle) chargers.   Can I suggest yet another alternative? 14 NiCd cells, at 1.35v each = 18.9V total. If you replace the AA cells with five 14500 LiIon cells, which are the same physical size, that would be: 5 * 3.6 = 18.0v There are plenty of smart chargers available for the RC market that can deal with a 5s battery pack. I have one of these: <https://hobbyking.com/en_us/imax-b6-50w-5a-charger-discharger-1-6-cells-genuine.html> Checking the specs, it charge 1 to 6 cells so it should work. If you need AC power, LiFePO4 charging, PC connectivity, upgradeable firmware, and terminal voltage adjust, the V2 version is what you want: <https://hobbyking.com/en_us/imax-b6ac-v2-professional-balance-charger-discharger.html>   I use nothing by the cheapest cells, which sucks because they usually only have about half the capacity and lifetime of a decent cell. However, they're cheap, and my use in mostly flashlight is not critical. <https://www.ebay.com/sch/Rechargeable-Batteries/48619/i.html?_nkw=14500+li-ion+battery> I haven't tried this brand, but at $1/ea, it's worth trying.   One potential problem with LiIon is if your unspecified device runs on +10 and -10 volts. 5 cells won't work but 6 cells might. It all depends on the operating voltage range of your unspecified device and on how it's wired/designed/configured.     -- 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

mike <ham789@netzero.net>: Apr 15 01:22AM -0700 On 4/14/2018 7:18 PM, Jeff Liebermann wrote: > critical. > <https://www.ebay.com/sch/Rechargeable-Batteries/48619/i.html?_nkw=14500+li-ion+battery> > I haven't tried this brand, but at $1/ea, it's worth trying.   Thanks, but the link takes me to page after page of cells. Can you disclose exactly which link is the one you've verified as reasonable cells? Better the devil you know than to take a random shot.   I've had horrible luck with any 18650's with "ultra" or "fire" in the name. I'd like not to repeat that with 14500's.

tabbypurr@gmail.com: Apr 15 04:02AM -0700 On Sunday, 15 April 2018 02:29:50 UTC+1, tabby wrote:   > Over here they're banned now. FWIW I had good results years ago with very old nicads, but yeah, the capacity isn't hot.   > I also wouldn't ignore the possibility of just using cheap new NiMH, if the capacity is enough.   > NT   or it might be easier to ask for a pile of NiCds on ebay     NT

John-Del <ohger1s@gmail.com>: Apr 15 07:05AM -0700 On Saturday, April 14, 2018 at 9:57:51 PM UTC-4, mike wrote:   > > So, is it true that Panasonic eneloop cells need a smart charger and does anyone know if anyone is making a quality nicad battery anymore? In the old days, I'd buy Sanyo nicads and although they'd often advertise less mah per cell than others, they seemed to last almost forever.   > There are a LOT of variables here. > It would be helpful to know what it is.   Trying to avoid that :) It's a Teknetics 9000 metal detector. Back when it was new, it was a high end detector. I don't know where I got it or even when, but there it is in my collection. My brother lost some keys last fall and has a pretty good idea where they are. He was going to buy a detector but I told him I have one so that's what prompted my inquiry.     > Are the batteries in series, parallel, separate supplies?   Series, but in two different banks of 8 and 6. If I feed in a dc supply on the 8 cell bank, the LCD display comes to life and the controls affect the display. If I put a supply on the 6 cell bank, it draws current but the LCD doesn't light. No, I haven't powered both simultaneously. I will before I order any batteries to confirm it's working.   > Is the OFF power drain really zero?   I think so. There is a physical switch for power.     > Is it gonna sit for a long time between uses?   Probably, although these are fun toys and I do have several acres of uncleared woods on my property to explore. One of my best friends has a house built in 1798 with an original rock wall and outhouse, so there's that.     > The best strategy is to charge the cells externally in a proper > charger and put 'em > back in when you're ready to use it.   I agree, but one of the banks of batteries had a leakage and several of the very thin battery contacts have disintegrated away. If I install batteries in it, it would be far more convenient to not have to physically remove them for charging.   I may have to rebuild the battery box with new contacts and go with external charging as you suggest. I was just looking for an easier way out (which is my defining personality trait...)   Thanks everyone.

Martin Riddle <martin_ridd@verizon.net>: Apr 15 11:28AM -0400 On Sat, 14 Apr 2018 13:42:27 -0700 (PDT), John-Del <ohger1s@gmail.com> wrote:     >The instructions show it has two recharge modes switchable from the front panel; recharge and store. The store is a very low trickle charge. Because it's from the early 80s, I'm assuming it's just a current limited charger (dumb charge) as it takes 14 hours to charge the entire group.   >I would have like to install eneloops in it, but anecdotal evidence suggests they don't like this type of charge, so I'm back at looking at regular nicads for it.   >So, is it true that Panasonic eneloop cells need a smart charger and does anyone know if anyone is making a quality nicad battery anymore? In the old days, I'd buy Sanyo nicads and although they'd often advertise less mah per cell than others, they seemed to last almost forever.   A few years ago I pickedup a Eneloop battery pack for a bearecat scanner.   It takes longer to charge, since the charger is a fraction of the eneloop capacity. I never had over heating issues. It probably never fully charged, but it's always ready to use.   Avoid the trickle charge.   Test it out, you'll be happy with the eneloops.   Cheers

"jfeng@my-deja.com" <jfeng@my-deja.com>: Apr 15 08:57AM -0700 On Sunday, April 15, 2018 at 7:05:10 AM UTC-7, John-Del wrote: > .... My brother lost some keys last fall and has a pretty good idea where > they are. He was going to buy a detector but I told him I have one so that's > what prompted my inquiry.   If you only need it once for a single job, I would just use alkaline batteries for a quick and easy fix. If necessary, use a couple battery holders and mount them externally. I assume that the circuitry will tolerate the slightly higher voltage, but if you are concerned, you could use one or two fewer cells in each pack.

"pfjw@aol.com" <peterwieck33@gmail.com>: Apr 15 08:56AM -0700 Ten years in service as of April 1. Makes our hot water, so operates year-round. Not one single glitch all these 10 years, but the service manual 'suggests' a firebox cleaning every five years or so. So, I purchased the kit ($59) and the cleaning tool ($29) and decided that this would be a good bit of PM to do while my new hip heals as I can do it sitting down.   Kroil is wonderful stuff. From reading on-line, it seems that these beast are notorious for seizing nuts and stripping studs. Given that, starting Saturday afternoon, I treated all the nuts and screws lightly, once again this morning. nothing seized or stripped, everything came off clean.   The old gaskets and heat-washers were pretty much done. The cover plate needed a bit of cleaning, I replaced the spark ignitor (included), cleaned the heat-exchanger - got about 1/3 cup of grit - and cleaned the site-glass. Checked the inhibitor levels (acceptable) cleaned the fire-cone, and put everything back together. Torqued the nuts per the sequence, fired it up, and off it went. Total time invested: about 2 hours.   I promise not to let it go 10 years, again, but this unit did not seem worse for the wear despite all that time. Note that this unit heats (well) our entire house (4,500 s.f.), so no complaints.   Peter Wieck Melrose Park, PA

pedro <me@privacy.net>: Apr 15 02:54PM +0800 On Thu, 12 Apr 2018 17:52:20 -0500, Jon Elson <jmelson@wustl.edu> wrote:   >Just 2 days idle during the weekend and they were in >trouble.   That sounds rather like Epson with separate heads/carts. Got so tired of trying to revitalise those that I swore off Epson completely.   Still have an olde HP900 series inker that seems to fire up fine about every six months, and a Canon that rattles/clunks/whirrs for about 90 seconds at every power-up. Good thing nearly all our printing needs are mono and met elegantly/economically with an HP Laser.

Bob Engelhardt <BobEngelhardt@comcast.net>: Apr 15 08:57AM -0400 I had a rarely used Lexmark (yearly cartridge replacement, more or less). I had it for years and never had a blockage. Only got rid of it because there was no driver for Windows 10.

John-Del <ohger1s@gmail.com>: Apr 15 08:31AM -0700 On Friday, April 13, 2018 at 2:37:30 PM UTC-4, N_Cook wrote: I've never seen an egg with streaks on it, so > difficult to believe that mechanism.     That's because Epson doesn't print eggs...

Jeff Liebermann <jeffl@cruzio.com>: Apr 14 11:26AM -0700 On Fri, 13 Apr 2018 15:57:55 -0700 (PDT), whit3rd <whit3rd@gmail.com> wrote:   >That greasy stuff (also available in waxy and rubbery forms) is thermal transfer compound; >like a grease, but it is NOT grease.   Well, it's called thermal grease, silicon grease, high viscosity semi-solid, or maybe magic grease. While not a lubricating petrochemical compound, it is a type of grease.   >It has to stay put in small crevices in order to work.   It also has to have a grain size small enough to fit in the crevices. >If you use a 'grease' formula instead of a 'thermal compound' formula, it might only >work for a few hours, then flow away.   Actually, it's worse than that. When heated, the viscosity of commodity silicon grease is lowered, making it flow easier. It also expands when heated. If I built a sandwich with a spring loaded heat sink, some thermal goo, and a CPU, the expansion and easier flow will cause the thermal goo to sloooowly ooooooze out of the sandwich. The spring tension (as found in some CPU coolers) will help prevent air gaps and thermal goo losses. Setting the spring pressure correctly is tricky. If too little, the assembly will eventually rattle. If too much pressure, and if too much thermal goo was added, it could potentially make a mess. Fortunately, as the thermal goo slowly ooooozes out from the sandwich with every thermal cycle, the gap between the heatsink and the CPU slowly decreases, causing an improvement in heat sink performance. That's why Arctic Silver and others mention that you should see lower temperatures after the thermal goo has had time to "break in" [1]. <https://archive.techarp.com/showarticle600c.html>   >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.   Yep. Actually, energy distribution is by the inverse square of the distance, but at tiny distances, it might as well be linear. Having too large a grain size will certainly ruin the thermal conductivity but not because they don't fit in the cracks. It's because large particles offer fewer points of contact between adjacent particles than smaller (nano) particles: Particle Radius Thermal Conductivity 50 micro meters 0.8 W/mK 1 micro meter 1.1 W/mK 0.003 micro meters 2.4 W/mK I don't have numbers handy for the grain size used in commodity thermal goo.     [1] <http://www.arcticsilver.com/as5.htm> Due to the unique shape and sizes of the particles in Arctic Silver 5's conductive matrix, it will take a up to 200 hours and several thermal cycles to achieve maximum particle to particle thermal conduction and for the heatsink to CPU interface to reach maximum conductivity. (This period will be longer in a system without a fan on the heatsink or with a low speed fan on the heatsink.) On systems measuring actual internal core temperatures via the CPU's internal diode, the measured temperature will often drop 2C to 5C over this "break-in" period. This break-in will occur during the normal use of the computer as long as the computer is turned off from time to time and the interface is allowed to cool to room temperature. Once the break-in is complete, the computer can be left on if desired.         -- 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

Jeff Liebermann <jeffl@cruzio.com>: Apr 14 11:54AM -0700 >>taking a step backwards. The bulk of the heat is passed by metal to >>metal contact.   >Smallest grain size is 1 micron. Or .0000039 Inches   or 39 micro inches (one too many zeros).   >My best surface plate is flat within 30 millionths of an >inch. My best set of gauge blocks, the ceramic ones, are +1 to + 3 >millionths in size except for the 4 inch block which is +4 millionths.   Arctic Silver 5 uses: <http://www.arcticsilver.com/as5.htm> Average Particle Size: <0.49 micron or <0.000020 inch or 20 micro inch. However, they use: "Arctic Silver 5 uses three unique shapes and sizes of pure silver particles to maximize particle-to-particle contact area and thermal transfer."   Crystalline diamond nanoparticles have an advantage, where the flat facet surfaces provide better thermal conduction than random, rough, or spherical shapes. <https://www.google.com/search?q=diamond+nanoparticles&tbm=isch>   Your diamond particles are twice the diameter, but considering the mix of sizes in Arctic Silver 5, the sizes are comparable. They should work if you decide to mix your own thermal goo. However, you can buy diamond thermal paste: <https://www.innovationcooling.com/products/ic-diamond/> The data sheet claims: Average Particle Size: <40 µ maximum particle diameter 40 micro what? inches or meters? Probably inches which is the same as your lapping compound.   If we made CPU's and heat sinks with the same precision as your gauge blocks, then we wouldn't need thermal paste or even mounting hardware. The two surfaces would stick together by themselves.   -- 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

N_Cook <diverse@tcp.co.uk>: Apr 14 06:49PM +0100 An added note relevant to repair. The rocking anchor of the escapement, is an early plastic, that holds the pallets with plastic move to lock plastic clamps. Like a lot of problems with early tape recorders using nylon like plastic, it can change dimension or relieve stress with age and bend or something, then something touches or disengages or something causing failure of the mechanism. In this case one o fthe tiny plastic clamps had loosened its grip on the receive side pallet, allowing the metal pallet to gradually move away from the escapement cog. Then the escapement escapes. Reset it to match the other pallet distance .

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