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Darned cheapie 9 volt batteries — Parallax Forums

Darned cheapie 9 volt batteries

whiteoxewhiteoxe Posts: 794
edited 2014-06-04 19:30 in General Discussion
I needed a 9 volt battery to do some first experiments with a servo motor. I was in a food shop and noticed some 9 volters for 2 bucks each. After running the servo for a few minutes it stopped. I had no clue. This just happened. I tested the battery and it was only giving out 6.2 volts. I hope that's why it stopped. Ill go out and get some good ones when the shops are open in an hour.

Comments

  • Phil Pilgrim (PhiPi)Phil Pilgrim (PhiPi) Posts: 23,514
    edited 2014-05-30 15:03
    The problem is not the particular battery that you bought, but 9V batteries in general. They are simply not suited for accommodating the current requirements of a servo.

    -Phil
  • Duane DegnDuane Degn Posts: 10,588
    edited 2014-05-30 15:12
    Phil Pilgrim (PhiPi) wrote: »
    The problem is not the particular battery that you bought, but 9V batteries in general. They are simply not suited for accommodating the current requirements of a servo.

    +1

    One of the first things we ask when someone is having trouble with a servo project is what kind of battery they're using. Use the 9V in a smoke detector and get some real batteries for the servo.

    Five AA NiMH cells are generally a good match for servos. As are LiPo or Li-Ion with a good regulator.
  • ercoerco Posts: 20,256
    edited 2014-05-30 18:43
    Yep, rechargeables are the way to go. Order some 18650 or 14500 cells & charger rom Ebay China. Very handy even if their actual capacity is much less than claimed.
  • whiteoxewhiteoxe Posts: 794
    edited 2014-05-30 20:14
    Well i got one of the better long lasting(so they say) batteries for $7 and everything is a go !!!t yes its a lot for one 9v battery.

    edit: when the program is at an END

    it dosent draw any power does it, my homework board does not have an off switch.?
  • Phil Pilgrim (PhiPi)Phil Pilgrim (PhiPi) Posts: 23,514
    edited 2014-05-30 20:18
    whiteoxe wrote:
    it dosent draw any power does it, my homework board does not have an off switch.?
    Yes, it stil draws power. You need to disconnect the battery to save it from draining.

    -Phil
  • whiteoxewhiteoxe Posts: 794
    edited 2014-05-30 20:22
    Duane Degn wrote: »
    +1

    One of the first things we ask when someone is having trouble with a servo project is what kind of battery they're using. Use the 9V in a smoke detector and get some real batteries for the servo.

    Five AA NiMH cells are generally a good match for servos. As are LiPo or Li-Ion with a good regulator.

    ok, but just while im using the homework board ill have to stick with 9V.
  • whiteoxewhiteoxe Posts: 794
    edited 2014-05-30 20:23
    thanks Phil, ill disconnect from now on.

    its a REV D, I GUESS THAT MEANS THERE WAS AN A, B, C ? youd think thered be a switch ;)


    If i put things like that on another breadboard and use the 4 AA cell powerpack, that 6volts would drive the servo ?
  • GenetixGenetix Posts: 1,754
    edited 2014-05-31 01:22
    The HomeWork Board never had an on/off switch.

    Also beware what kind of batteries you are buying because I often see cheap batteries are standard or Heavy Duty, especially 9V.
  • whiteoxewhiteoxe Posts: 794
    edited 2014-05-31 05:30
    Picture 12.jpg


    Ive got a couple of these edge detectors with 3 pins, no idea how to connect them.
    Picture 12.jpg
    640 x 480 - 76K
  • idbruceidbruce Posts: 6,197
    edited 2014-05-31 06:25
    Whiteoxe

    This is nothing personal intended against you, but I have been scolded by Parallax for using punctuation marks in a sentence. Although a misspelling, the first word in your title is one of the first words I was forbidden to say as a child. I am truly surprised that Parallax has not scolded you :) Don't worry, I won't report you :)
    I am just saying....
  • PJAllenPJAllen Banned Posts: 5,065
    edited 2014-05-31 07:38
    $2 = "cheapie" ??
    If I had your money then I could burn mine.
    whiteoxe wrote: »
    Ive got a couple of these edge detectors with 3 pins, no idea how to connect them.

    +5, Gnd, out to an input ?
    +5, Gnd, and then out to a voltmeter - to see how it goes? (Roll with that can you?)
  • Ken GraceyKen Gracey Posts: 7,392
    edited 2014-05-31 09:13
    PJ Allen wrote: »
    $2 = "cheapie" ??
    If I had your money then I could burn mine.

    PJA never ceases to make me laugh out loud. I think PJA wouldn't burn his money on 9Vs for this purpose, but he'd rather go for a higher current, large capacity 6-7V supply.

    Ken Gracey
  • whiteoxewhiteoxe Posts: 794
    edited 2014-05-31 09:40
    idbruce wrote: »
    Whiteoxe

    This is nothing personal intended against you, but I have been scolded by Parallax for using punctuation marks in a sentence. Although a misspelling, the first word in your title is one of the first words I was forbidden to say as a child. I am truly surprised that Parallax has not scolded you :) Don't worry, I won't report you :)
    I am just saying....
    Bruce, hi, i dont believe you got scolded for using punctuation....are you serious ;) I know a cheapie is not a Dame :)
  • whiteoxewhiteoxe Posts: 794
    edited 2014-05-31 09:42
    PJ how much is a 9volt where u live ????

    i ended up paying $6 which was less expensive than the ones beside it.
  • PJAllenPJAllen Banned Posts: 5,065
    edited 2014-05-31 11:05
    whiteoxe wrote: »
    PJ how much is a 9volt where u live ????

    My point was that I do not regard $2 as "cheapie". :zombie:

    Anyway, with regard to the IR module since that was made part of this topic, I got mine out and did some experimenting.
    +5 to its VCC, Gnd to its Gnd, and output to the voltmeter.
    There's no modulation going on. It's just a comparator there, a threshold detector.
    There's a Red LED for power.
    There's a Green LED that turns on, and the Output goes Low, when there's anything getting reflected back to the receiver.
    I turned the pot back counter-clockwise and the Green LED went out. I turned the pot CW a tweak and I could detect my finger in front of it (< 1/8_in).

    At full CCW it's "least sensitive", it won't trigger without a lot of signal reflected back.
    At full CW it's subject to ambient light and so on.

    PE - Just wanted to note here that I haven't had any acknowledgement of the information provided, but the OP has been back to change his avatar several times since. I just don't get it.
  • MoskogMoskog Posts: 554
    edited 2014-05-31 11:32
    erco wrote: »
    Yep, rechargeables are the way to go. Order some 18650 or 14500 cells & charger rom Ebay China. Very handy even if their actual capacity is much less than claimed.

    Sorry, Erco I strongly disagree on buying batteries from China (http://forums.parallax.com/showthread.php/152959-Beware-of-fake-batteries-on-ebay!?highlight=batteries+china) Better spend the money and buy quality batteries in a store near you.
    I buy from China several times a week, so I'm also an Ebayer like you, but no more batteries!
  • Too_Many_ToolsToo_Many_Tools Posts: 765
    edited 2014-06-01 13:05
    whiteoxe wrote: »
    I needed a 9 volt battery to do some first experiments with a servo motor. I was in a food shop and noticed some 9 volters for 2 bucks each. After running the servo for a few minutes it stopped. I had no clue. This just happened. I tested the battery and it was only giving out 6.2 volts. I hope that's why it stopped. Ill go out and get some good ones when the shops are open in an hour.

    FWIW...a few weeks ago Radio Shack was blowing out their brand line of batteries for $1.49 a pack...an excellent deal for alkalines.
  • idbruceidbruce Posts: 6,197
    edited 2014-06-01 15:03
    whiteoxe
    Bruce, hi, i dont believe you got scolded for using punctuation....are you serious

    Yes, I was serious, and appropriately scolded. The point was that young minds come here to learn, therefore Parallax wants to keep the site as child friendly as possible, which is very understandable. I normally try to set a good example for youngsters, but occassionally an adult member gets under my skin, and I lose my cool. So instead of using unmentionable words, I used punctuation marks and got scolded :)
  • ercoerco Posts: 20,256
    edited 2014-06-01 17:48
    Idbruce: Did you mean "whiteoxe"? :)
  • idbruceidbruce Posts: 6,197
    edited 2014-06-01 18:07
    erco
    Yes I did :) Sorry whiteoxe, misspelling corrected :)
  • Too_Many_ToolsToo_Many_Tools Posts: 765
    edited 2014-06-02 11:22
    FWIW...Radio Shack has been clearancing its lithium 9v batteries for $0.97.
  • whiteoxewhiteoxe Posts: 794
    edited 2014-06-04 13:48
    PJ Allen wrote: »

    PE - Just wanted to note here that I haven't had any acknowledgement of the information provided, but the OP has been back to change his avatar several times since. I just don't get it.

    Sorry, i did appreciate your help. I just have not been ready to add those to the new bot im building. It will be very useful when i do so thanks,
  • GenetixGenetix Posts: 1,754
    edited 2014-06-04 19:30
    TMT, I don't where you saw those batteries because they only batteries I can find for that price are Zinc-Chloride.
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