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Re: Batteries
On Sun, Mar 2, 2025 at 02:18 PM, Roy J. Tellason, Sr. wrote:
The YT channel "Project Farm" does all sorts of comparison tests on a lot of stuff, and he did one video comparing different brands, some of which I'd never heard of. He arrived at the conclusion that lithium was the way to go, that they didn't leak, and offered better performance than any of the alkaline cells that were out there. Now by "lithium" - do you mean the NON-rechargeable, super-long-life lithium 1.5 V cells?? The ones that cost $20 for a pack of four AA's?
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I use those for the outside thermometer so it won't freeze, but I reserve it for that only because they cost so much.
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If I'm not mistaken, they are guaranteed to have at least 10 or 15 years of shelf life.
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It is unfortunate that there are so many cells and batteries named "lithium" these days.? Some electronics insists "NO lithium batteries!" but of course they are talking about the lithium-ion rechargeables (which are nowhere near 1.5 V), not the non-rechargeable lithium cells (which are about 1.5 V).
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Andy
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Re: Batteries
On Sun, Mar 2, 2025 at 02:18 PM, Roy J. Tellason, Sr. wrote:
These days if you look at the battery rack in the front of a Wal-Mart near the registers, it's pretty much more Eveready than anything else.Interesting.? That's not what I see here.? (I stopped going to Walmart during early COVID and mostly haven't been back.)? These days I see tons of Duracell and few of others.? I'm sure each retailer has their preferences.? Less supply-demand, more what they want to put on their shelves, as long as it moves. ?
Andy
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Re: Batteries
wn4isx
The Everready >primary< AA and AAA and 9V lithiums do not have a drop down regulator.
Just disassembled a dead AA and 9V.
They are pricey but probably worth it for several reasons...
For test gear I seldom use, the 10 year life expectancy means the test gear will probably work when I need it, and, if the lithium goes flat, it won't leak.
For devices like our blood pressure machine, used everyday, a set of lithiums last about 3 times as long as alkylines with no risk of leakage.
For the flashlights in the cars, given the 10 year life expectancy, I can count on having them work when I? need them.
My primary reason for adopting them was lack of leaking and no corrosion, and I pay through the nose for the cells / batteries.
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Re: Batteries
On Sun, Mar 2, 2025 at 07:41 AM, Bertho wrote:
I don't know, but I expect they all use crimped seals of? one form or another, and the quality of those seals (a manufacturing step where they can save money) surely comes into play.? Even if they use the same cell wall thickness, if the seal fails, it's no good.
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They are not likely to inspect them after sealing them.
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I remember a story some 20 years ago, how car batteries from the same "American" name brand companies suddenly became noticeably lighter, because they started using significantly thinner lead.? I think it coincided with using a different Chinese supplier for the American name brand.
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Andy
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Re: Batteries
I don't know if this is relevant.? ?But one of the stated characteristics of Leclanche cells was an initial open-circuit voltage of about 1.4 V, which rapidly falls off.? Whereas carbon/zinc dry cells are supposed to be a little above 1.5 V, and all the ones I played with, measured close to 1.6 V when new.
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And I still wonder why the only person in the world I have ever seen call them Leclanche cells, is here in this group.? Nobody else ever calls them that.? Why is that?? Is it because few of the people I know are chemists?? But surely many of them are engineers, and none of the engineers I know ever called them that.? Even some chemists don't call them Leclanche either.
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I have your word, or I have my years of experience, to go on here.? Which do you think I am inclined to believe?
How does one give a cell a "reverse charge"?? What does it even mean? ?
It implies doing a partial DIScharge first.? Is that it?? I'm assuming it does not mean to discharge until the voltage reaches 10% negative, but like I said, I don't understand.
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Does it help only with "non-rechargeable" dry cells?? Or does it apply to rechargeables too?
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Andy
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Photo Notifications
#photo-notice
Group Notification
Dave <theschemer@...> added the photo album Lorex Wifi Camera : An image of the circuit board of my Lorex Wifi security camera that has lost it's effective range. The following photos have been uploaded to the Lorex Wifi Camera photo album of the [email protected] group. By: Dave <theschemer@...> |
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Re: Wireless Camera repair
On Sat, Mar 1, 2025 at 02:27 PM, Dave wrote:
I'd be concerned about the word "outdoor" in that sentence.
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Being exposed to the elements opens up at least a few cans of worms.? Including corrosion.? Or frozen (compromised) components.? Some of that you might not be able to easily see.
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Andy
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Re: Wireless Camera repair
I just realized that the problem is likely just the wifi card that the antenna connects to. Problem is that it's likely proprietary and? not obtainable.
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On 3/2/2025 10:41 PM, wn4isx via groups.io wrote:
Is the screw on connector mounted on the PCB or is there a jumper? |
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Re: Wireless Camera repair
I just opened it up with a Phillips head screwdriver and all the connections look ok. The antenna connection is on the frame or housing of the camera and looks in fine shape. It travels through the adjustable angle connector and into the main housing. It's all SMT in there but after a quick look I see no issues and the wire from the antenna connects the same way a wifi card in a laptop does and it looks fine. I may look at it at a later date under the microscope but the way its assembled even if I did find and replace a bad SMD component (and they are really small) it would be a real pain to re-assemble it and probably wouldn't work anyway. I will post a pic if the circuit board just so you can see what I have.
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Thanks On 3/2/2025 10:41 PM, wn4isx via groups.io wrote:
Is the screw on connector mounted on the PCB or is there a jumper? |
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Re: Batteries
开云体育Question about the Lithium AA cells - I know they use a little buck regulator to get the voltage down to 1.5V (nominal) but that also means that they are current-limited. Finding out the current limit on the advertised products it "deucedly" difficult. Have you ever tried the glow plug test on a Li AA cell? Many TIA, On 3/2/25 14:37, Roy J. Tellason, Sr.
via groups.io wrote:
On Sunday 02 March 2025 01:49:59 am Andy via groups.io wrote:On Sat, Mar 1, 2025 at 01:30 PM, wn4isx wrote:****The "less likely to leak" has become a joke, all the major brands now leak long before their use by date. **** [snip] The YT channel "Project Farm" does all sorts of comparison tests on a lot of stuff, and he did one video comparing different brands, some of which I'd never heard of. He arrived at the conclusion that lithium was the way to go, that they didn't leak, and offered better performance than any of the alkaline cells that were out there. |
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Re: Wireless Camera repair
wn4isx
Is the screw on connector mounted on the PCB or is there a jumper?
Most cameras I've worked with have a short, 5" or so, jumper with a press on RF connector on the PCB.
A few have the SMA directly on the BCB and the center connector can come unsoldered or the trace to it break. The break can be so microscopic it might be impossible to see, ohm out with a meter on low ohms, I'd use the diode measurement function.
Good luck. These things can drive a man to distraction.
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Re: Wireless Camera repair
开云体育I will see if I can get into the camera and post pics of what I find or see inside. I probably have the correct tools to get into it as I have some gun tool kits that have an assortment of bits along with other large plastic box kits with various bits. I think I already mentioned I tried a new antenna and this camera uses a screw on type like a coax cable. I will post back when I know more. Thanks On 3/1/2025 2:39 PM, wn4isx via
groups.io wrote:
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Re: Batteries
On Sunday 02 March 2025 01:49:59 am Andy via groups.io wrote:
On Sat, Mar 1, 2025 at 01:30 PM, wn4isx wrote:That may be changing, we'll see.If rumors are to be believed (I know, there's a major problem with that), then some brands are considerably better than others in this respect. I went through a period where I tried all sorts of brands. Dollar store brands, etc. And I arrive at the conclusion that the name brands like Duracell and Eveready would last longer than any of those other ones. Yeah, you can get a whole big honkin' box of those other ones fairly cheaply, but who wants to be bothered with changing them more often? I used to favor Duracell, but they had a period of time where they seemed to be more prone to leakage. These days if you look at the battery rack in the front of a Wal-Mart near the registers, it's pretty much more Eveready than anything else. OTOH, I have a couple of Duracell D size that I pulled out of a magliite flashlight after realizing that they'd been in there close to a decade and a half, There's a date of "MAR 2013" on them And they still test good! The YT channel "Project Farm" does all sorts of comparison tests on a lot of stuff, and he did one video comparing different brands, some of which I'd never heard of. He arrived at the conclusion that lithium was the way to go, that they didn't leak, and offered better performance than any of the alkaline cells that were out there. One time when I was still in high school I picked up a "glow plug" at a hobby shop, the sort of thing you'd use for a model airplane engine. And just for the heck of it I connected it up to a AA alkaline cell, and sure enough that little heating element glowed. So I got curious and measured the current. I was really surprised to see that it was over an amp! I had no idea that you could pull that much out of one of those.... -- Member of the toughest, meanest, deadliest, most unrelenting -- and ablest -- form of life in this section of space, ?a critter that can be killed but can't be tamed. ?--Robert A. Heinlein, "The Puppet Masters" - Information is more dangerous than cannon to a society ruled by lies. --James M Dakin |
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Re: Batteries
On Sunday 02 March 2025 01:29:11 am Andy via groups.io wrote:
On Fri, Feb 28, 2025 at 04:03 PM, Roy J. Tellason, Sr. wrote:You don't need to cut anything open. Just grab one corner of the sheet metal where it joins with a pair of needle nosed pliers, and twist. Keep going like that and eventually you peel all of the metal off. Early 9V batteries had six smallish rectangular cells stacked, but the current alkaline ones have six AAAA cells standing up.The only place I've ever seen AAAA being used was in laser pointers. AndMy wife has something that uses one.? I think it goes with her tablet.? From about 5 years ago. I don't have anything around here that uses them. Some stuff here uses AAA, which is annoying enough. Going from AAA to AA you get almost 3 times the power out of it... -- Member of the toughest, meanest, deadliest, most unrelenting -- and ablest -- form of life in this section of space, ?a critter that can be killed but can't be tamed. ?--Robert A. Heinlein, "The Puppet Masters" - Information is more dangerous than cannon to a society ruled by lies. --James M Dakin |
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Re: Wireless Camera repair
On Saturday 01 March 2025 03:39:00 pm wn4isx via groups.io wrote:
If you can open the case, many security devices use "odd" screws, you might find the antenna connector popped loose. Most of these connectors are press fit and not 'real' microwave cables.Harbor Freight has a set of bits like that too. They've pretty much covered my needs when I encounter some of that weird stuff. I try not to do business with amazon to the extent possible. :-) -- Member of the toughest, meanest, deadliest, most unrelenting -- and ablest -- form of life in this section of space, ?a critter that can be killed but can't be tamed. ?--Robert A. Heinlein, "The Puppet Masters" - Information is more dangerous than cannon to a society ruled by lies. --James M Dakin |
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Re: Batteries
开云体育One more battery detail: Pagers (beepers) used N-cells and later AA-cels.? Mercury cells were popular with the much longer life. I collected dead cells and recovered the mercury that I then refined. Designing the RF and IF sections was not easy.? From the single cell, there was a linear regulator so only 0.975V was available at a couple of mA. Bertho |
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Re: Batteries
wn4isx
On Sun, Mar 2, 2025 at 10:48 AM, wn4isx wrote:
I wrote:
They started out dry but the electrolyte was replaced with magnesium dioxide and they became 'dry.' That should have been?
They started out wet but the electrolyte was replaced with magnesium dioxide and they became 'dry.'
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I'm still on codeine cough syrup and it sure shows. Glad I don't have to drive anywhere today. |
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Re: Batteries
wn4isx
Nobody but engineers and chemists called them by their proper name.
Leclanché cells were the first practical "dry cell." They started out dry but the electrolyte was replaced with magnesium dioxide and they became 'dry.' [damp really] Of course "as deployed" they were quite different from the original and featured additions/modifications by several people.
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https://www.sciencedirect.com/topics/engineering/zinc-carbon-battery
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I took a class in the "physics of electrical cells" in 'university' and learned the proper name.
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Most of us called them carbon-zinc batteries being ignorant that a battery is a collection of cells.
I cringe when I hear people call a "D" cell a battery.
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You can actually recharge carbon-zinc/Leclanché cells. They don't recharge all that well, the only place I could see the process being worthwhile was for a night watchman, use one set and recharge the other.
Going from a vague memory, each recharge lost about 5% of capacity. Typically recharging ended when the process ate through the zinc shell.
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There was a long series of letters to the editor in one of the magazines about how to improve charging.
One thing that appeared to have helped was to have about 10% reverse charge during the process.
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Everready [or one of the battery companies] actually sold a commercial charger.
I don't think you can recharge alkaline cells at all. even charging the carbon-zinc was a loss leader.
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The university class was interesting because it helped me understand "Primary batteries are burning metal to produce electricity." Not exactly accurate but it gets the idea across. We visited Oak Ridge and saw a liquid sodium battery. Good energy to weight ratio but molten sodium is pretty energetic if there is a leak.
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At the time, silver-cadmium had the best, as in highest energy to weight ratio, they were prone to memory just like nickle-cadmium but handled temperature extremes better. Of course they were somewhere so far beyond obscene expensive only the military and NASA could use them. The US Navy OSCAR series used them. The Nike' Zeus missile defense missiles would have also used them.?
[Been to one Nike' Zeus as they demolished it. Interesting site.]?
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Note: The Navy OSCAR and amateur Oscar only share names and have nothing else but being satellites in common.
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Bertho
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