battery chargers, again
in [Design]
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From: Joerg on 29 Sep 2009 16:29 John Larkin wrote: > On Mon, 28 Sep 2009 19:28:39 -0500, krw <krw(a)att.bizzzzzzzzzzz> wrote: > >> On Mon, 28 Sep 2009 09:06:34 -0700, John Larkin >> <jjlarkin(a)highNOTlandTHIStechnologyPART.com> wrote: >> >>> On Mon, 28 Sep 2009 09:04:17 -0500, Tim Wescott <tim(a)seemywebsite.com> >>> wrote: >>> >>>> On Sun, 27 Sep 2009 21:16:46 -0700, John Larkin wrote: >>>> >>>>> Last time a car went dead in the garage, my wife's Fit, I hacked up a >>>>> charger from an old DSL wall-wart and a sabre saw as a series current >>>>> limiter. The garage geometry makes it essentially impossible for us to >>>>> push a car uphill to the street to jump it. Now The Brat left her Echo >>>>> in the garege for a month or so and it went dead, too. So I figure it's >>>>> time to buy a real charger. Went to Kragen Auto Parts and bought two >>>>> (one for here, one for Truckee) chargers. They are all "smart chargers", >>>>> namely switchers with electronics, these days. >>>>> >>>>> The battery is really dead, 1.8 volts. The first charger hums and >>>>> outputs nothing. Tried the next one: it hummed for maybe 3 seconds then >>>>> sparked and smoked inside. >>>>> >>>>> Went back to Kragen and traded up, two better chargers. Neither >>>>> charges... no current, battery steady at 1.8 volts. Both have their >>>>> "charging" LEDs off and "charge complete" LEDs lit. >>>>> >>>>> Back to Kragen, 3rd time, got all my money back. Passed by Bob Pease's >>>>> place all three trips, same collection of rusty VWs everywhere. >>>>> >>>>> A charger that puts zero amps into a dead battery does that by design, >>>>> and there's only one reason to do that: to convince people they need a >>>>> new battery. Kragen's sales pitch was exactly along those lines; "Tt >>>>> won't charge, so all the cells are shorted." >>>>> >>>>> So I went to work and nabbed a cute little Lascar bench power supply. It >>>>> current limits at 1.2 amps, so I just cranked it up. The battery went >>>>> instantly to 16.5 volts, then settled down to 12 or so in a few minutes, >>>>> and is creeping back up. >>>>> >>>>> Interesting. >>>>> >>>>> So I guess I'll buy a couple of 3 amp or so lab supplies, with nice volt >>>>> and amp meters, instead of battery chargers. They're handier to have >>>>> around anyhow, cost about the same as a "good" charger, and aren't booby >>>>> trapped. >>>>> >>>>> What Kragen is doing is fraud. >>>>> >>>>> John >>>> I've never had a battery come back from being that dead, and I've had >>>> numerous chances to try it (I'm stubborn that way). You'll be lucky to >>>> see 12V out of it with the charger disconnected, and I doubt that you'll >>>> see that after the first time you touch the key. If you _do_ get the car >>>> started it'll just be an opportunity for you daughter to get stranded >>>> some place. >>> It started OK after about 6 hours at 1.2 amps, started vigorously >>> after charging all night. My wife's car was zero-volts dead a couple >>> months ago, got rebooted from the DSL wall-wart, and it's fine. >>> Lead-acids will sulphate and lose capacity if they sit dead for a long >>> time. >>> >>>> One new battery is cheaper than one tow truck ride. Do the math. >>> Our insurance covers the truck ride. >> It's the brat's vehicle, IIRC. I wouldn't beg *any* trouble for a >> woman's vehicle. ...for more reasons that I can count. The brat's, >> never. > > She left the Echo - her high school car - in our garage because all > she wants to drive now is her Jeep Rubicon. Gotta get her to sell the > Echo so we can have our garage back. > Why is everyone spoiling their kids so much? Same with the daughters of a business friend, they got cars courtesy of daddy. Plus tuition, room and board at rather ritzy colleges. I had to work for my first car. Dad wanted to chip in to get me a somewhat decent looking used car upon nailing my masters but I said I should really try to pay my own way. And did. Couldn't possibly show up for interviews in my old Citroen but the TUEV had just blown it out of the water anyhow, declared it unroadworthy. You could see the road surface fly by when looking down. > http://www.rubicon-trail.com/ > > But if her car battery did go dead, she wouldn't have any trouble > getting a jump start. > Like Keith, I'd be concerned about what happens afterwards ... -- Regards, Joerg http://www.analogconsultants.com/ "gmail" domain blocked because of excessive spam. Use another domain or send PM.
From: VWWall on 29 Sep 2009 17:00 Jim Thompson wrote: >> The topper was a rented and I might add, very pricey, Agilent spectrum >> analyzer. Did EMC debug at a client, rolled up my sleeves and by >> afternoon had the unit shipshape. Or so I thought. Fired up the >> analyzer, and many nasty spikes in the 250MHz region were still there. >> Bit my lips so no cussing would slip out. How is this possible ...? >> Turned off unit under test, spikes still there. Hurumph! Turned out they >> emerged from the analyzer display. I had to go to a hardware store >> there, buy some sort of chicken coop fencing and drape that over the >> analyzer's face. Turned DUT back on, total silence. Pathetic. I should >> have take a photo and sent it to Carly back then. >> I thought Agilent had split from HP before Carly took over. Many years ago a rep wanted me to look at a new line of spectrum analyzers. He set one up connected to an output directional coupler on a tube in the magnetron line at WE's plant and got a fine looking spectrum on the screen. I reached over and disconnected the co-ax from the coupler. The display on the screen didn't change at all! I asked the rep: "Which one of these ten tubes under test are we looking at." -- Virg Wall, P.E.
From: Joerg on 29 Sep 2009 17:09 VWWall wrote: > Jim Thompson wrote: > >>> The topper was a rented and I might add, very pricey, Agilent >>> spectrum analyzer. Did EMC debug at a client, rolled up my sleeves >>> and by afternoon had the unit shipshape. Or so I thought. Fired up >>> the analyzer, and many nasty spikes in the 250MHz region were still >>> there. Bit my lips so no cussing would slip out. How is this possible >>> ...? Turned off unit under test, spikes still there. Hurumph! Turned >>> out they emerged from the analyzer display. I had to go to a hardware >>> store there, buy some sort of chicken coop fencing and drape that >>> over the analyzer's face. Turned DUT back on, total silence. >>> Pathetic. I should have take a photo and sent it to Carly back then. >>> > I thought Agilent had split from HP before Carly took over. > Yeah, but she dunnit: http://en.wikipedia.org/wiki/Carly_Fiorina Quote "Although the decision to spin-off the company's technical equipment division predated her arrival, one of her first major responsibilities as chief executive was overseeing the successful separation of the unit into the standalone Agilent Technologies." All I can say is that I like the lab gear they made before the split a lot better. > Many years ago a rep wanted me to look at a new line of spectrum > analyzers. He set one up connected to an output directional coupler on > a tube in the magnetron line at WE's plant and got a fine looking > spectrum on the screen. I reached over and disconnected the co-ax from > the coupler. The display on the screen didn't change at all! I asked > the rep: "Which one of these ten tubes under test are we looking at." > Did he have it in some sort of digital phosphor mode? -- Regards, Joerg http://www.analogconsultants.com/ "gmail" domain blocked because of excessive spam. Use another domain or send PM.
From: VWWall on 29 Sep 2009 17:30 Joerg wrote: > VWWall wrote: >> Jim Thompson wrote: >> >>>> The topper was a rented and I might add, very pricey, Agilent >>>> spectrum analyzer. Did EMC debug at a client, rolled up my sleeves >>>> and by afternoon had the unit shipshape. Or so I thought. Fired up >>>> the analyzer, and many nasty spikes in the 250MHz region were still >>>> there. Bit my lips so no cussing would slip out. How is this >>>> possible ...? Turned off unit under test, spikes still there. >>>> Hurumph! Turned out they emerged from the analyzer display. I had to >>>> go to a hardware store there, buy some sort of chicken coop fencing >>>> and drape that over the analyzer's face. Turned DUT back on, total >>>> silence. Pathetic. I should have take a photo and sent it to Carly >>>> back then. >>>> >> I thought Agilent had split from HP before Carly took over. >> > > Yeah, but she dunnit: > > http://en.wikipedia.org/wiki/Carly_Fiorina > > Quote "Although the decision to spin-off the company's technical > equipment division predated her arrival, one of her first major > responsibilities as chief executive was overseeing the successful > separation of the unit into the standalone Agilent Technologies." > > All I can say is that I like the lab gear they made before the split a > lot better. > About a year ago, I got an old HP 200-A Audio Oscillator out of my garage, where it had been for forty plus years. I had to replace the line cord--(Los Angeles smog had got to the rubber...) I turned it on and it worked perfectly! I didn't even re-form the electrolytic caps. The leather "Handle" had deteriorated, but there's even one listed in the parts manual! They don't make 'em like that anymore. > >> Many years ago a rep wanted me to look at a new line of spectrum >> analyzers. He set one up connected to an output directional coupler >> on a tube in the magnetron line at WE's plant and got a fine looking >> spectrum on the screen. I reached over and disconnected the co-ax >> from the coupler. The display on the screen didn't change at all! I >> asked the rep: "Which one of these ten tubes under test are we >> looking at." >> > > Did he have it in some sort of digital phosphor mode? > This was a line making the magnetrons for the NIKE search RADAR. They were multi-megawatt S-band tunable units, and there was RF all over the production test line. The instrument obviously needed better shielding! Nobody had heard of digital at that time. (1950) -- Virg Wall
From: Joerg on 29 Sep 2009 17:41
VWWall wrote: > Joerg wrote: >> VWWall wrote: >>> Jim Thompson wrote: >>> >>>>> The topper was a rented and I might add, very pricey, Agilent >>>>> spectrum analyzer. Did EMC debug at a client, rolled up my sleeves >>>>> and by afternoon had the unit shipshape. Or so I thought. Fired up >>>>> the analyzer, and many nasty spikes in the 250MHz region were still >>>>> there. Bit my lips so no cussing would slip out. How is this >>>>> possible ...? Turned off unit under test, spikes still there. >>>>> Hurumph! Turned out they emerged from the analyzer display. I had >>>>> to go to a hardware store there, buy some sort of chicken coop >>>>> fencing and drape that over the analyzer's face. Turned DUT back >>>>> on, total silence. Pathetic. I should have take a photo and sent it >>>>> to Carly back then. >>>>> >>> I thought Agilent had split from HP before Carly took over. >>> >> >> Yeah, but she dunnit: >> >> http://en.wikipedia.org/wiki/Carly_Fiorina >> >> Quote "Although the decision to spin-off the company's technical >> equipment division predated her arrival, one of her first major >> responsibilities as chief executive was overseeing the successful >> separation of the unit into the standalone Agilent Technologies." >> >> All I can say is that I like the lab gear they made before the split a >> lot better. >> > About a year ago, I got an old HP 200-A Audio Oscillator out of my > garage, where it had been for forty plus years. I had to replace the > line cord--(Los Angeles smog had got to the rubber...) > > I turned it on and it worked perfectly! I didn't even re-form the > electrolytic caps. The leather "Handle" had deteriorated, but there's > even one listed in the parts manual! They don't make 'em like that > anymore. Cool. I have Tripplite inverter in the garage where there are instructions printed on, outlining how to order new Germanium power transistors for it, along with the phone number and all. That is from the days where it was expected that the average camper and outdoorsman is fully able and willing to whip out the solder iron and replace a transistor while having a beer and watching the pork chops on the barbie. >> >>> Many years ago a rep wanted me to look at a new line of spectrum >>> analyzers. He set one up connected to an output directional coupler >>> on a tube in the magnetron line at WE's plant and got a fine looking >>> spectrum on the screen. I reached over and disconnected the co-ax >>> from the coupler. The display on the screen didn't change at all! I >>> asked the rep: "Which one of these ten tubes under test are we >>> looking at." >>> >> >> Did he have it in some sort of digital phosphor mode? >> > This was a line making the magnetrons for the NIKE search RADAR. They > were multi-megawatt S-band tunable units, and there was RF all over the > production test line. The instrument obviously needed better shielding! > Whoops. > Nobody had heard of digital at that time. (1950) > Oh, Konrad had :-) http://en.wikipedia.org/wiki/Z1_(computer) -- Regards, Joerg http://www.analogconsultants.com/ "gmail" domain blocked because of excessive spam. Use another domain or send PM. |