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T i m <news@spaced.me.uk>: Sep 26 05:26PM +0100 On Tue, 26 Sep 2017 06:46:01 -0700 (PDT), tabbypurr@gmail.com wrote:   <snip>   >> supply is greater?   >> That seemed like the best of all worlds (for the KISS solution)?     >You want a zener with a nice straight line at the low current end. One linked to from here has that.   Yeah, ok ... but what about the question re using a lower value zener to get it away from the 'knee', especially as it's no more difficult to do?   Cheers, T i m

Foxs Mercantile <jdangus@att.net>: Sep 26 02:30PM -0500 On 9/26/2017 11:26 AM, T i m wrote:   > Yeah, ok ... but what about the question re using a lower value zener > to get it away from the 'knee', especially as it's no more difficult > to do?   Here it is again. The simplest is a 20K resistor in series with a 10v zener diode. Use a low current Zener so the knee works right at low values. Something like this: <http://www.mouser.com/ds/2/395/BZX55C2V0%20SERIES_D1610-1099630.pdf> Note, this is a DO-35 package.   -- Jeff-1.0 wa6fwi http://www.foxsmercantile.com

mike <ham789@netzero.net>: Sep 26 02:13PM -0700 On 9/26/2017 9:26 AM, T i m wrote: > to get it away from the 'knee', especially as it's no more difficult > to do?   > Cheers, T i m   Since we're just trying to be clever, Try this:   https://i.imgur.com/irLisN7.jpg   The transistor and zener make a temperature compensated ~7V reference (must use 6.2V zener with standard tempco). Two pots set the min and max voltages. Rk allows you to add current to the zener to get it past the most nonlinear portion of it's V-I curve. This circuit has the ability to calibrate out almost any component variation. It's relatively temperature independent. You can use any meter that will make full scale at less than about 7V. Downside is that the pots are vibration sensitive and subject to moisture/corrosion.   Are we having fun yet?

tabbypurr@gmail.com: Sep 26 03:29PM -0700 On Tuesday, 26 September 2017 17:26:46 UTC+1, T i m wrote: > to get it away from the 'knee', especially as it's no more difficult > to do?   > Cheers, T i m   The zeners with the straightest knee are at 9-10v. Go look at the linked data sheets.     NT

T i m <news@spaced.me.uk>: Sep 27 01:40AM +0100 On Tue, 26 Sep 2017 14:13:20 -0700, mike <ham789@netzero.net> wrote:   <snip>   >> to get it away from the 'knee', especially as it's no more difficult >> to do?   >Since we're just trying to be clever,   I'm not mike, I'm just trying to refine the design of any solution to be as good as possible with the fewest possible components. ;-)   >https://i.imgur.com/irLisN7.jpg   >The transistor and zener make a temperature compensated ~7V >reference (must use 6.2V zener with standard tempco).   Ok.   >Two pots set the min and max voltages.   Noted.   >Rk allows you to add >current to the zener to get it past the most nonlinear portion >of it's V-I curve.   Understood.   >This circuit has the ability to calibrate out >almost any component variation.   That sounds like the sort of thing I was hoping to hear. ;-)   >It's relatively temperature >independent.   As long as it will cope with the -10 to +10 DegC range it should be fine here in the UK. ;-)   >You can use any meter that will make full scale at >less than about 7V.   And that's most small panel meters I'm sure.   >Downside is that the pots are vibration sensitive >and subject to moisture/corrosion.   Sure, but in my case they won't be subject to any real vibration and will be in a sealed enclosure. Also I would typically use a quality multiturn pot of the smallest value possible to give me sufficient 'trimming' around the end points and quality resistors to do the main bridge / work.   >Are we having fun yet?   Well, it's certainly bringing some interesting and varied solutions out of the woodwork. ;-)   It might also help me use up my stock of BC107's. ;-)   Cheers, T i m

T i m <news@spaced.me.uk>: Sep 27 01:49AM +0100 On Tue, 26 Sep 2017 15:29:19 -0700 (PDT), tabbypurr@gmail.com wrote:   <snip>   >> to get it away from the 'knee', especially as it's no more difficult >> to do?   >The zeners with the straightest knee are at 9-10v.   Ok, so again that helps because I'd go for a 9V zener to get AFA I can from that 10V threshold and still retaining the sharpest knee. ;-)   >Go look at the linked data sheets.   Too much information (variables) for me in most cases mate. ;-)   Ah, you can use the 9V zener but it only comes in SM and you have to buy 1000. The 10V are easier to get but need a higher current ... etc etc. I don't play chess or poker or any game of chance for that matter (preferring FPS when I can shoot my fellow players in the face). ;-)   The whole point to me of asking those who know is they are the ones who should all agree on a single 'best' solution. ;-)   More than one way to skin a cat? (But for that as long as it does get skinned is good enough for me [1]).     Cheers, T i m   [1] I couldn't hurt one but I don't see the point in them ... apart from a source of whiskers for crystal sets and guts for violins. ;-)

Foxs Mercantile <jdangus@att.net>: Sep 26 08:00PM -0500 On 9/26/2017 7:49 PM, T i m wrote: > Too much information (variables) for me in most cases mate.;-)   You keep missing it.   Here it is again. The simplest is a 20K resistor in series with a 10v zener diode. Use a low current Zener so the knee works right at low values. Something like this: <http://www.mouser.com/ds/2/395/BZX55C2V0%20SERIES_D1610-1099630.pdf> Note, this is a DO-35 package.     -- Jeff-1.0 wa6fwi http://www.foxsmercantile.com

John-Del <ohger1s@gmail.com>: Sep 26 05:00PM -0700 > that sort of melted from the flames.   > Shipping is extra.   > Post a reply if you want to buy it!       LOL!   Not to get too far from your post but your story reminded me of a true story my dad told me. Back in the late 1950s or early 60s, he was making a house call on a B&W console. He arrived at the house and found it on the front porch. Turns out the grandfather was watching TV while the TV was literally on fire. His daughter and son-in-law ran into the room when they smelled the smoke and there was grandpa watching that TV en fuego. He wasn't aware of the flames licking the curtains because the show he was watching was a western and either the wagon train or the barn was set on fire by the Indians (er, Native Americans) and was in full blaze.

dplatt@coop.radagast.org (Dave Platt): Sep 26 12:42PM -0700 In article <hiljsctonehbkmnnivrp1mu59osrc2j29t@4ax.com>,   >My question is whether I can use a common spray paint on bakelite, such >as Rustoleum? I may not get the exact color as original, but I dont see >any way to get the original paint.   http://www.radiomuseum.org/forum/vintage_radio_restoration_bakelite_radio_cabinets.html has a good discussion of this.   He doesn't mention any specific sort of paint being required, but does recommend spraying on a coat of primer after a thorough cleaning... probably a good idea to help ensure good adhesion.   I recall that Rustoleum makes some paint varieties which are specified as being suitable for use on plastics. This sort of multi-surface paint might give you some additional defense against peeling, if you decide to omit the primer step.

rickman <gnuarm@gmail.com>: Sep 26 05:14PM -0400 Dave Platt wrote on 9/26/2017 3:42 PM: > as being suitable for use on plastics. This sort of multi-surface > paint might give you some additional defense against peeling, if you > decide to omit the primer step.   It all depends on the details. I used a paint for plastic to use on a plastic container and it did not work well at all. I cleaned the surface well, but did not rough it up and did not use a primer. It was not too long before the paint started to peel. I don't know the type of plastic. It was a food storage container with a seal ring commonly available in stores. Just a data point for what it is worth.   --   Rick C   Viewed the eclipse at Wintercrest Farms, on the centerline of totality since 1998

tabbypurr@gmail.com: Sep 26 03:31PM -0700 On Tuesday, 26 September 2017 22:14:42 UTC+1, rickman wrote:   > before the paint started to peel. I don't know the type of plastic. It was > a food storage container with a seal ring commonly available in stores. > Just a data point for what it is worth.   Nothing sticks to polythene.     NT

tabbypurr@gmail.com: Sep 26 03:33PM -0700 On Tuesday, 26 September 2017 20:42:20 UTC+1, Dave Platt wrote: > as being suitable for use on plastics. This sort of multi-surface > paint might give you some additional defense against peeling, if you > decide to omit the primer step.   I've seen seasoned restorers use car spray paint, vauxhall brazil brown for bakelite.   When getting a colour match I always give the sample a good clean first, otherwise the wrong colour is inevitable.     NT

rickman <gnuarm@gmail.com>: Sep 26 06:43PM -0400 >> a food storage container with a seal ring commonly available in stores. >> Just a data point for what it is worth.   > Nothing sticks to polythene.   Are you in the UK? Is that what we call polyethylene? How does it happen that we end up with different names for things like common plastic?   --   Rick C   Viewed the eclipse at Wintercrest Farms, on the centerline of totality since 1998

tabbypurr@gmail.com: Sep 26 03:53PM -0700 On Tuesday, 26 September 2017 23:43:46 UTC+1, rickman wrote:   > > Nothing sticks to polythene.   > Are you in the UK? Is that what we call polyethylene? How does it happen > that we end up with different names for things like common plastic?   Yes, yes, it's easier to say. Polythene is the next best thing to ptfe when you want to keep friction low. Handy for moving heavy loads. Food storage containers are most commonly polythene.     NT

dplatt@coop.radagast.org (Dave Platt): Sep 26 04:16PM -0700 >> Nothing sticks to polythene.   >Are you in the UK? Is that what we call polyethylene? How does it happen >that we end up with different names for things like common plastic?   Tradition. It dates back at least as far as the day when we Americans decided we couldn't afford to spell the new metal "aluminium" due to a severe shortage of printers' slugs for the letter "i". :-)

"David Farber" <farberbear.unspam@aol.com>: Sep 26 02:10PM -0700 David Farber wrote:   > Yes, that matches what the old part is. I'm in no hurry so I'll wait > to see what diodes.com has to say.   > Thanks for your reply.   I finally had time to install the new transistors and they worked perfrectly. The cats are happy again!   Thanks for all your helpful replies. -- David Farber Los Osos, CA

bruce2bowser@gmail.com: Sep 26 02:28PM -0700 > > will only be let back in if they are not bringing anything with them.   > Bad move!   > Your cats think that you are a particularly incompetent hunter, eat all kinds of weird, smelly, dead food and generally are not very good cats. So, they are trying to feed you, and train you as they would their kittens.   That's really the explanation?

tabbypurr@gmail.com: Sep 26 03:42PM -0700 > > Bad move!   > > Your cats think that you are a particularly incompetent hunter, eat all kinds of weird, smelly, dead food and generally are not very good cats. So, they are trying to feed you, and train you as they would their kittens.   > That's really the explanation?   You could ask one, but IME they're inclined to be secretive.     NT

dplatt@coop.radagast.org (Dave Platt): Sep 26 03:26PM -0700 In article <oqefp1$98r$1@dont-email.me>,   >I finally had time to install the new transistors and they worked >perfrectly. The cats are happy again!   Excellent - very glad to hear it!

Steve Goldstein <sgoldHAM@alum.mit.edu>: Sep 26 07:02PM -0400 Does anybody have schematics or repair info for this scale or one of the other V-series models? My V-350 worked fine when carefully put on a shelf a few months ago, but when I tried to use it today it wouldn't boot up. It showed all the display segments briefly, but then hung with only the tiny arrow in the upper left of the display showing, and was unresonsive to the CAL and TARE buttons (though I could turn it off and on with the switches).   Thanks.

N_Cook <diverse@tcp.co.uk>: Sep 26 07:22PM +0100 Silly wind-up torch but could be anything using Ni-Cad or ni-Mh multi-cells. LEDs are full bright for a short time after winding up , then drops to low light level, regardless of amount of winding beforehand. One cell is out of kilter with the rest, and in use discharges quickly compared to the others. Bench ps charging that one , in isolation, cures the problem. But presumably it may return , unbalanced charge/discharge across the cells. How to do the isolated charging of one cell properly, the next time in the way of monitoring voltages and charge currents ?

"Ian Field" <gangprobing.alien1@virginmedia.com>: Sep 26 10:27PM +0100 "N_Cook" <diverse@tcp.co.uk> wrote in message news:oqe5sp$qmg$1@dont-email.me... > But presumably it may return , unbalanced charge/discharge across the > cells. How to do the isolated charging of one cell properly, the next time > in the way of monitoring voltages and charge currents ?   The one i bought was total crap - you can get them with a charging jack, they might be less of a disaster.

tabbypurr@gmail.com: Sep 26 03:45PM -0700 On Tuesday, 26 September 2017 19:22:21 UTC+1, N_Cook wrote:   > Bench ps charging that one , in isolation, cures the problem. > But presumably it may return , unbalanced charge/discharge across the > cells.   likely discharge in the cell from a dendrite. If so the cell's at end of life.   > How to do the isolated charging of one cell properly, the next > time in the way of monitoring voltages and charge currents ?   The easiest way is just overcharge them, but it must be done at slow charge, ie 16hr charge rate.   The practical answer is new cells. They're very cheap.     NT

Dusty <Dusty@DustyDustyDusty.com>: Sep 26 11:57AM -0700 Nothing on reliability ! As usual reviewers do not know how to review. What is most important to you ?   Their second top rated is the one that died.   Other parameter metrics are of little interest.   Buying a Sony 32G as the one I already have has been the best.   Why ? The Sony has worked at every USB port I have tried it on. The Sandisk only works on some USB ports. Why ? because the Sony connector is a better quality connector and can make up for the deficiencies of the USB PC connector. I have several SanDisk pen drives and with some I have to wiggle the pen drive for it to make a connection. Not so with the Sony. The SanDisk skimps on it connector length and area trying to save a penny and putting their fingers in my purse. Poor quality connector !   The Sony has more reliability and quality. So I pay a few bucks more but it is well worth it.     Bob_S wrote:

harry newton <harry@is.invalid>: Sep 26 06:03PM He who is Piet said on Tue, 26 Sep 2017 10:16:57 +0200:   >> or build the bezel such that there is uneven support, and it >> can easily break.   > And *that* is the whole issue.   JF Mezei & Piet bring up good on-topic points where the question is whether Apple outright lied or not, and if they did outright lie, why they did so.   If it's true that the *material* is the "strongest ever" put on a smarphone, then we'd have to look at two things that Apple said & meant: a. What Apple literally said, and, b. What Apple meant their mostly factually-clueless customers to perceive   It's hard to believe that one of the finest, if not the finest, marketing organizations in the world would need to stoop to an outright lie to get its customers to appreciate the product, so, the statement that they didn't lie outright about the "material" holds credibility.   Is the "lie" explained as simply as: a. The "material" is the strongest ever put in a smartphone, but, b. The "implementation" is as weak as any (and even weaker than some).   Is that a rational explanation of Apple's statements as compared with fact?

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