Dead amp?

Discussion in 'Hi-Fi and General Audio' started by daws0n, Sep 20, 2009.

  1. daws0n

    daws0n

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    I bought a Denon PMA250iii from a local boot sale last week, thought I had a bargain for a tenner but I've just tried it out and it won't power up :mad:

    I've changed both fuses - in the mains plug and the internal 25a fuse. No life at all, does anyone have any resurrection tips before it goes out with the trash?

    Dawson
     
    daws0n, Sep 20, 2009
    #1
  2. daws0n

    RobHolt Moderator

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    Hi Dawson,

    A couple of things to try:

    Can you measure the voltage at either side of the transformer?
    At the side connected to the amplifier circuits you should be getting something like 35v AC.
    If you get nothing, try measuring the input and determine that the 240v mains is getting to the transformer.

    If the whole thing is dead and you have checked all fuses, try bypassing the mains on/off switch as these can sometimes fail.

    Be careful of course - MAINS KILLS!
     
    RobHolt, Sep 20, 2009
    #2
  3. daws0n

    daws0n

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    Voltage check sounds like a plan, but I haven't got a multimeter at the moment... I think i'll invest - it will also come in handy testing PC components. By passing the on/off button sounds like a good idea, how would I do this?

    I may ask the local AV shop how much they'd charge to take a basic look at it, but if it's at all expensive it's not worth it considering the price I paid.

    Still, I'm not that bothered as I had some good buying luck too - picked up a pair of *working* Mission M761's and a lovely set of Wharefedale Denton 2 XPs for the grand total of 6 quid :)
     
    daws0n, Sep 20, 2009
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  4. daws0n

    Deaf Cat

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    If your very close to Bicester, it may be worth dropping Kevin at the audiocellar and email, he may be able to help, he offered to check out my pre amp processor for a very reasonanble price and fix it if it was simple while I waited - where local shops quoted between £37 and £50 just to have a look !
    £10 worth a gamble though - hopefully one of the tips Rob mentioned will sort it :)
     
    Deaf Cat, Sep 20, 2009
    #4
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