Connect with us

Question about ac adapters

Discussion in 'General Electronics Discussion' started by Hi Im Larry, Mar 18, 2012.

Scroll to continue with content
  1. Hi Im Larry

    Hi Im Larry

    Mar 18, 2012
    I was given a Sylvania SYNET07526 Netbook that doesn't have a charger. The DC Input reads 9V, 1.5A. I was able to find a charger I got that reads:

    Input: 100-250v ~ 30w 50/60hz
    Output: DC - 9v 2.2a

    I don't know anything about what could go wrong if I attempted to plug it in with this, so I figured I'd ask people who know more about it than I do. Is it fine or should I just go buy one for it?

    Thanks for any help.
  2. (*steve*)

    (*steve*) ¡sǝpodᴉʇuɐ ǝɥʇ ɹɐǝɥd Moderator

    Jan 21, 2010
    Make sure the polarity is correct (that's the BIG thing to check).

    The fact that the charger you've got is rated for more current than is required is GOOD. This means the charger won't be stressed by having to operate flat out and will thus run cooler and almost certainly last longer.
  3. cjdelphi


    Oct 26, 2011
    You'll be fine, just make sure (@) (pin in the middle may be positive or negative) so just make sure that's fine and connect away.
  4. cjdelphi


    Oct 26, 2011
    if it is wrong, it's as simple as cutting the cable and flip the 2 connecting wires, if you're still not sure, use a multimeter and slice the cable off, and measure the resistance to the plug on the end of the cord with the 2 wires, you'll be able to locate the positive terminal like that..

    Really is beyond me why still some electronics fail to come with a protection diode, seriously chinese guys, what's an extra 10cents on a protection diode!!!
  5. KJ6EAD


    Aug 13, 2011
    Most but not all coaxial DC connectors for that voltage will be center pin positive and the case near the socket will have a tiny diagram showing the polarity.

    If you end up replacing the plug on the adapter, the following may be useful.

    The pin diameter will likely be 2.1mm and the plug diameter will likely be 5.5mm. There are two plug/socket lengths, 9mm & 12mm.

    The Chinese guys say adding a diode will increase the unit cost, reduce the profit margin and reduce repeat sales; all unacceptable. :rolleyes:
    Last edited: Mar 19, 2012
  6. (*steve*)

    (*steve*) ¡sǝpodᴉʇuɐ ǝɥʇ ɹɐǝɥd Moderator

    Jan 21, 2010
    And the engineers tell you that the diode will dissipate around 1W and contribute to the power dissipation without really adding anything (because you'd never use anything other than the correct charger, right?).

    edit: yes, BobK, you were right (before your edit to remove it)
    Last edited: Mar 20, 2012
  7. BobK


    Jan 5, 2010
    Never mind.
    Last edited: Mar 20, 2012
Ask a Question
Want to reply to this thread or ask your own question?
You'll need to choose a username for the site, which only take a couple of moments (here). After that, you can post your question and our members will help you out.
Electronics Point Logo
Continue to site
Quote of the day