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Re: Batteries
wn4isx
Talk about an EMI source that exceeds FCC Part 15 radiation limits!
Bet it wipes out RF from DC to light.
I had a pair of welding goggles for use with mine and still couldn't look directly at the arc.
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The only thing brighter I was part of involved the magnesium chassis of a piece of military avionics.
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Ya see I'd stripped the electronics and had this 10 pound chassis of magnesium....some friends and I decided to visit the hill above my Daddy's family home for a January MW (AM broadcast band) mini DX [DX is radio talk for distant) reception. We wanted to receive England directly. Strung a real long wire, 2 wavelenths at 1MHz, fired up our radios and had a blast.
At bedtime I tossed the chassis in the fire when no one was watching.
I expected it to catch fairly quick but it took almost a half hour, but when it caught it was magnificent.
It was so bright we had to turn out backs to the fire and the light reflecting from falling snow flakes was so bright they hurt to look at.
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About an hour later the sheriff and concerned members of society [my kin armed for bear] showed up with some hard questions. I had a reputation but managed to look quite innocent, "Bright light you say? Damn must have slept through it." I don't think I convinced anyone of my innocence but there was no proof, magnesium ash looks like wood ash and no one was going to take samples to a lab.
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My friends and I still giggle and whisper "Man that was bright."
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I bet aircraft overhead saw it through the snow and clouds.
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Yea it was that bright.?
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I have a dozen magnesium sacrificial rods for water heaters and I've been tempted every July 4 to show the locals what bright is. They'd realize how pathetic their sparklers are....
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Someday I'll talk about that military surplus Star Cluster Illuminator I found.....
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Re: A downright amazingly stupid LED headlight, I'm impressed.
wn4isx
On Fri, Feb 28, 2025 at 11:55 AM, Kenneth G. Gordon wrote:
KenA friend's daughter is a trauma physician and calls motorcycles donorcycles. ?
I had too many close calls to count, only one was my fault and that one proved God does look out for fools and children.
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About a year ago I was in a car parts place to pick up some stuff, stepped out and saw a young man get nailed by a car. He was in a marked crosswalk (yea that makes life so much safer for pedestrians). He was OK, busted up and a cop insisted on calling for the EMTs. The guy didn't want to leave his Russian clone of a BMW motorcycle in the parking lot so I volunteered to drive it to his home. He lived 6 or 7 blocks away, called his wife to lead me there and bring me back.
The bike was smooth, handled well but reminded me "Fool you are 72, you have no business doing this!"
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Crosswalks are booby traps. I had a car slide through a crosswalk at a red light, barely missing my wife and I, then the fool slammed it in reverse and laid rubber backing up. The cop next to him was seriously unamused. The fool argued with the cop and was arrested. So unsad.?
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Re: A downright amazingly stupid LED headlight, I'm impressed.
BTW, your URL is missing a DOT after www.
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Here is the "corrected" URL. Ken W7EKB On 28 Feb 2025 at 8:35, wn4isx via groups.io wrote:
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Re: A downright amazingly stupid LED headlight, I'm impressed.
I rode/drove/almost-died-more-than-once on motorcycles for awhile when I was much
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younger and a bit more stupid than I am now. I have an over-worked guardian angel. Harley-Davidson. Almost big enough to damage a car if it hits one. Their wheels are big enough to act as gyroscopes, making it difficult to turn or lean at high-speeds. Ask me how I know this. Did you ever drive one by simply lightly pushing on the ends of the handlebars with your index fingertips? Ever hear of precession? In Italy, motorcycles are called "The Doctors' Friend".with good reason. Ken W7EKB On 28 Feb 2025 at 8:35, wn4isx via groups.io wrote:
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A downright amazingly stupid LED headlight, I'm impressed.
wn4isx
A friend and fellow idiot sent me this link ? https://www.tesladownunder.com/WorldsBrightestBike.htm#BikeLights ? I am impressed and bow down to this guy. [and I'm glad I live nowhere close to him.] ? I gave up bicycles when I turned 16 for motorcycles with the logic "Now I can outrun cars...." ? They still don't see you, even at night with your headlight on drivers will cut you off with frightening regularity. I gave up on motorcycles after seeing two young riders get splatted by a 'queen mary' [any large car] while driving down the road. The bikers were in their lane driving sanely, the cars just ran them down. ? Anyway, the light from a Honda CA-77, CB-350, CB-360 wasn't anything to write home about and it was easy to outdrive your headlight, outdrive refers to driving faster than you can see ahead. [perhaps one shouldn't drive 80MPH on narrow back roads.....] ? Now this headlight would let you see far enough ahead to be useful....but blind the poor sod coming at you so he'd probably splat you. ? While I've kept my motorcycle endorsement, that's more because I'm stubborn then practical. There is no way I'd ride a motorcycle unless my life depended on it. I suspect my artificial knees would be most displeased. ? Consider the project as proof humans can do amazingly stupid things....I'm proud to be a member of such an inventive species. Worry about our long term survival chances, but what the heck, we can have fun in the mean time. ? |
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Re: Batteries
开云体育I too build an arc lamp: I used ?” carbon rods and a full-sized arc welder.? It was very noisy! I focused the beam.? It was ?about 10kWatt. Later I rectified and filtered the AC to DC and added a series loading inductor. It was amazing!? Almost no sound, just a hiss. I have been thinking of firing it up again and making a video. Bertho ? From: [email protected] <[email protected]> On Behalf Of wn4isx via groups.io I built an arc light using the carbon rods ground down to points. Brighter than the sun and almost as hot. I used an electric space heater as the ballast to limit the current, arcs have positive temperature coefficients, the draw more current as they heat up.? ? |
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Re: Batteries
wn4isx
If you use a cheap standard Lanche' cell, the carbon rod will generally be present.
Just checked for the fun of it. Really messy.
I used "D" cells from Krogers.?
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I built an arc light using the carbon rods ground down to points. Brighter than the sun and almost as hot.
I used an electric space heater as the ballast to limit the current, arcs have positive temperature coefficients, the draw more current as they heat up.?
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My parents were seriously 'not amused' at that project. Almost got barred from experimenting for a month.
The fact I sat the workbench in the garage on fire might have had something to do with their anger. But I did put the fire out before did any major damage...of course the smoke was rather intense. My dad cut new boards and made me replace the damaged ones.?
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I was allowed a lot of freedom but power tools were strictly off limits. Given my clumsiness, I can't say I blame my parents edicts. I'm amazed my parents didn't sell me to the circus.
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Given the number of times I shocked myself silly, I'm amazed they didn't restrict me to reading books on philosophy.
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Re: Batteries
wn4isx
Going way back in time, radios used 3 batteries
A Battery powered the filament, very few tubes had indirectly heated cathodes, the filament was the cathode because it was so much more efficient.? Some filaments were coated with barium or cesium [rare) for improved electron emission.
B Battery, for the plate. Typically 22.5 or 40V
C Battery, for bias, these went away when someone figured out you could place a low value resistor in the cathode to ground leg of the tube to produce a "negative" voltage for the grid.
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At various times the A, B, and C were combined, and, at other times the A and B were combined.
The A battery typically had the shortest life because filaments required more power then the plates.
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Note: "Battery" sizes, "D", "C", "AA" "AAA" have nothing to do with function.
There were "B" cells at one point. I think with the introduction of the "AA", the "A" and "B" cell went away, this would have been the late 1950s.
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I've read "A" cells are still used in Europe, they are combined in a single case to power small lantern batteries. [I've never been to Europe so I have no idea if that statement is accurate.]
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In the good old days, 1960~1970, US lantern batteries consisted of 4 "F" cells. A "F" cell was the same diameter as a "D" but longer. Today most US lanturn batteries use "D" cells
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An "AA" and "C" are the same length, I've wrapped tape around an AA so it's work in my wife's wall clock.?
I didn't feel like running out and buying a "C" cell. Hillbilly Engineering at it's finest. The "C" cell lasted about a year, the "AA" lasted about a year.
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Almost everyone is familiar with the rectangular 9V battery, at one time, 1960ish, there was a round 9V battery about the size of a "C" cell. It had more amp hours [ok mA hours] then the rectangular one but transistor radio design improved to where the extra capacity wasn't needed and the single double contact snap was easier for people to use. Heath offered a 100mW superheterodyne CB HT that used the round 9V battery. I was at an air show in 1964 or 65 [or 66 or 63] and a CAP member had to change the battery in his HT.
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Technobable nonsense. If you reversed the receive and transmit crystals for US CB channel 10, the HT would be on the CAP 'channel.' You'd have to retune the RF stages for optimal performance, but it was an inexpensive way for CAP members to get on the air. I had a Lafayette HT with a blown TX stage and reversed the CH 10 Rc and Tx crystals so I could listen to CAP. They were extremely active for a few years in Lexington, then sort of faded away.?
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Re: Batteries
When I was young, we had one of those AC/battery powered tube radios.? It was the only one I remember seeing but I'm sure they weren't that uncommon.? I never saw the innards, but I imagine the B+ probably was 90 V or so.? No vibrator, it was straight DC, or the AC>DC supply.
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What I remember about it was that the case of the radio was made out of what seemed to be very heavy durable cardboard.? Funny thing.
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In the old old days, I'm told you brought your battery-powered radio to a repair shop where they outfitted it with new batteries.? I think you could go several months on a charge before needing to replace batteries.? And then they came up with a way to run them on AC, and everything changed.? And then, decades later, they came up with a way to run them on batteries, and everything changed again.
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Andy
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Re: Batteries
wn4isx
I'd have to dig through my "lab notebooks." All in 3 photocopy boxes filled with notebooks and sheets of paper. I'm recovering from bronchitis, my wife would have called 911 last Friday night if she hadn't had her knee replaced on January 31 and isn't quite up to managing alone, so don't want to breath the dust. ? So, going from a 60 year old memory, something like shown https://www.scribd.com/document/132869868/12V-to-120V-Inverter ? Note: This is not the way to do it today. Use CMOS chips to drive MOSFETs, lower loss from collector to emitter. ? Tripplite used a similar design with heavy duty germanium power transistors in their 150W 12>120V inverter. ? My unit almost certainly didn't produce anything near 60Hz, but it worked. I'm amazed at how well a lot of my projects worked when I was somewhere beyond clueless. Of course a fair percentage were total failures. I tried to build a FM wireless mic....with a germanium transistor when I was 9. I didn't have a clue about Ft. Now the FM wireless mic with a pair of tunnel diodes did work, range about 500 feet. Yep, certainly violated Part 15 of the FCC rules. ? And my Tesla Coil got me in trouble when it sat the wallpaper on fire.... My mother disassembled that unit with a frightening amount of anger.... ? ? To Bertho 120F.....two of them. Bet that got a bit expensive. How do they handle temperature extremes? The spec sheets I've seen mentioned serious problems below 32F. [of course that was 20 years ago.] ? ? ------------ General comment, don't do this unless you know what and why you are doing it. I needed 90V one night RFN to check a surplus 6M military radio. ? I was in Eastern Kentucky between Jackson and Hazard. Sort of limited on options....but the grocery store (IGA) had 9V batteries. ? I used 10 9V batteries, snapped the positive from one to the negative of the next. Ugly as sin, delicate as a ...er flower, but it worked. ? I've been told I think out side the box. ? There are boxes we are supposed to think in? |
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Re: Batteries
On Thursday 27 February 2025 10:03:09 am wn4isx via groups.io wrote:
Hey it was a lot cheaper then a 600V battery!I remember running into stuff that used various batteries whose voltage tended toward higher than flashlights, 15V, 22-1/2V, 30V, 45V, 67-1/2V, and 90V. Some projects in sixties Popular Electronics actually used 90V batteries. I was dealing with some garage door openers that used the 15V ones, but that situation involved a lot of constant downward price pressure and I eventually walked away from it. Back when I was doing the battery store gig, a guy came in with a portable flourescent ilght and wanted to know if I could get him a battery for it. I can't recall exactly, but I think it was something like 130V. Unobtainium at the time... Given a transformer with a center-tapped winding, say 12VCT to 120V, how would you make an oscillator that would work with that? I have plenty of salvaged transistors of all sorts, going all the way back to TO-3 germanium parts, though I'd be more inclined to go with TO-220. I remember a guy (sadly no longer with us) who described a setup he had with a couple of germanium power transistors in an oscillator that was powered by a couple of dissimlar metal plates that were buried in his yard. As long as there was at least some moisture in the soild that setup actually generated some usable power, on a very small scale. I never did get the details of that from him, unfortunately. -- 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I use dual 120F capacitors in our solar powered LED street markers that are embedded in the highways. DOT regulation requires the lights to be able to be lit for at least 16 hours/night. Bertho |
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Re: Batteries
wn4isx
As Donald pointed out, alkaline cells/batteries have a fairly high internal resistance, the old carbon zinc Leclanché? cells had an even higher internal resistance. ? [I had to go pick up a prescription and checked out the battery rack and found old style carbon zinc Leclanché? cells are still available, I'm not sure why anyone would try and save the few pennies difference in price, but then some people are even cheaper than me.] ? It's much like using CR3032, or other lithium button cells, to power a LED. It's almost always perfectly safe to overvoltge the LED because of the high internal resistance of the button cell drops the voltage to a safe value. ? My wife won a 6 cell Mag flashlight with a "psychedelic" color scheme in the anodized aluminum case. She loves the thing but hated the way it ate batteries. [God help the person who tries to attack her when she's got it out. I suspect it'd make one heck of a club.] ? I replaced the incandescent bulb with a LED and new reflector then used "AA" to "D" adaptor shells. It's about 3 times as bright and the cells last about 5? times as long. ? Note: Drop in LED replacement bulbs for incandescent bulbs for "Mag flashlights" are inexpensive but the original reflector isn't optimized for a LED. It's worthwhile the extra expense to go with a combined LED/reflector. [or buy a new LED flashlight for about 1/10 the cost.] ? The book goes into such things as internal resistance, response to cold and heat, etc. ? I use 1F [yes 1 Farad] capacitors to replace the CRxxxx memory backup cells in my Kenwood R-2000s and iCom IC-28A. I salvaged the 1Fs from Kenwood "keep alive while shipping" commercial 2-way 900MHz radios. They've been in service since the summer of 1990. I just turned on a R-2000 that has a really messed up encoder reader. You can tune the radio but it will take an hour to tune to a desired frequency. It's tuned to WWV on 2.5/5/10/15/20 and the US AF global HF network primary and secondary frequencies. It hadn't be turned on, or connected to power, in at least 3 years. All memories were still there. ? For the truly demented among you, with oodles of money to waste on experiments.... Electronic Goldmine offered G28718 ^' Eaton 62 Farad 18.0V 3.7KW Peak Power Energy Storage Module XTM-18R626-R ? Eaton Supercapacitor Storage Module is rated 62 Farad 18.0V. Size is 9-1/4" x 1-5/8" x 3" tall. Has 2 screw terminals for power hookup. New! Retails for $189.69. ? From the Eaton webpage https://www.eaton.com/za/en-gb/skuPage.XTM-18R0626-R.html Peak Current (1 second) 235.6A ? My Toyota Echo draws 97A @60F when starting. Takes about 4 seconds, so, could I use 4 or 5 of these? At ~$600? ? These would make a nice very short term 12V power rail back up for short power outages. ? One of the "magic" ways electric vehicles maximize battery life and driving range is to use the drive motors as generators when braking, they dump the electricity into high value capacitors, then draw the electricity to start/accelerate. ? I am not into NASCAR but was at a friend's home one evening and his daughter loves NASCAR. I was impressed by how quickly the front brake would turn red nearly white from heat with what appeared to be modest braking. ? Braking clearly wastes a lot of energy, capturing it for reuse in an EV is impressive. ? Re vibrators. I tore a dead one apart when I was 7, still remember the odd smell from the sound deadening rubber insulation. I used a relay as a 'vibrator' for my first home made Geiger counter when I was 8. The vibrator drove the 6V CT with a lantern battery (this was when lantern batteries used "F" cells instead of "D" cells.) of a salvaged transformer. A 3 stage voltage multiplier produced 600-700V. It would charge a capacitor that gave 10 minutes of "click time" before needing to recharge. I was 10 when I replaced the relay with transistors. ? I eventually learned enough to build a real voltage multiplier, use a cross coupled pair of transistors to drive a 12V CT > 120V transformer and step the ~120ish volt to 620. I used Neon bulbs to inhibit the oscillator when the voltage was 620ish. ? I thought I was a genius.? Hey it was a lot cheaper then a 600V battery! ? |
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Re: Batteries
I remember in my high school days (1956) of removing the vibrator in many friends cars, banging it on the curb and putting it back in. This broke the "welded" contacts and restarted the pulsed signal to the transformer primary. One of my friends watched me do this and when his radio failed, grabbed the big filter capacitor and yanked it out of the chassis. Needless to say I had a lot more work to fix his radio. Dan Kahn On Thursday, February 27, 2025 at 12:56:22 AM EST, Andy via groups.io <ai.egrps@...> wrote: On Wed, Feb 26, 2025 at 07:39 PM, wn4isx wrote: I wondered when you might go there!? :-) ? My only experience with vibrator power was in the automobile's radio which of course used vacuum tubes (late '50's).? We almost never turned it on.? I think the reason was fear that it would fail about every 5 times it was switched on, and nobody likes bringing the car to the service station to fix the darned radio AGAIN. ? At first I thought you were taking this topic in the direction of flashlights.? I remember my dad's big metal flashlight, which had five (yes, five) "D" cells to power one 6 Volt bulb in a big reflector.? Now wait a minute.? That's 7.5 V, powering a 6 V incandescent bulb?? To be sure, the flashlight was very bright.? I think we know why. ? Were incandescent bulbs rated in such a way that you could run them about 25% over-voltage and they happily worked and didn't give up the ghost?? It seems like a great way to make a super bright flashlight but one that went through bulbs faster than it did batteries.? And yet it did not burn out its bulbs.? It makes one wonder.? Maybe it drew so much current from the "D" cells so that their nominal voltage dropped significantly?? I wonder. ? Back to batteries.? My first exposure to NiCads was the HP-35 calculator in about 1972.? All I knew about NiCads was that NASA had experience using them in satellites, which is where they learned about their dreaded? "memory effect". ?
Might be worth looking into, even at my age. ? Wow, there are so many new battery technologies - every month or so - that have 1000 times the capacity of last month's invention, so that surely by now they must be capable of powering an entire city for a year on one simple set of rechargeable batteries.? Yeah, right. ? Andy ? |
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Re: Batteries
开云体育I'll opine that the filament actually only saw about 6V when
turned on. The old Carbon-Zinc D cells had a quite high internal
resistance.
indicates that current Energizer D cells have an initial internal
resistance of 170mOhms or so. (I'm pretty sure the older ones were
about 2-3x higher.) Lamps drawing 500mA would see less than the
7.5V of five D cells in series. Donald. On 2/27/25 00:56, Andy via groups.io
wrote:
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Re: proper way to connect single ended to differential circuits
On Tue, Feb 25, 2025 at 07:34 AM, john23 wrote:
I think you can figure that out. ?
Andy
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Re: Batteries
On Wed, Feb 26, 2025 at 07:39 PM, wn4isx wrote:
I wondered when you might go there!? :-) ?
My only experience with vibrator power was in the automobile's radio which of course used vacuum tubes (late '50's).? We almost never turned it on.? I think the reason was fear that it would fail about every 5 times it was switched on, and nobody likes bringing the car to the service station to fix the darned radio AGAIN.
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At first I thought you were taking this topic in the direction of flashlights.? I remember my dad's big metal flashlight, which had five (yes, five) "D" cells to power one 6 Volt bulb in a big reflector.? Now wait a minute.? That's 7.5 V, powering a 6 V incandescent bulb?? To be sure, the flashlight was very bright.? I think we know why.
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Were incandescent bulbs rated in such a way that you could run them about 25% over-voltage and they happily worked and didn't give up the ghost?? It seems like a great way to make a super bright flashlight but one that went through bulbs faster than it did batteries.? And yet it did not burn out its bulbs.? It makes one wonder.? Maybe it drew so much current from the "D" cells so that their nominal voltage dropped significantly?? I wonder.
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Back to batteries.? My first exposure to NiCads was the HP-35 calculator in about 1972.? All I knew about NiCads was that NASA had experience using them in satellites, which is where they learned about their dreaded? "memory effect".
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Might be worth looking into, even at my age.
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Wow, there are so many new battery technologies - every month or so - that have 1000 times the capacity of last month's invention, so that surely by now they must be capable of powering an entire city for a year on one simple set of rechargeable batteries.? Yeah, right.
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Andy
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Bertho