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Ouch.... Is it knackered?

Discussion in 'audio' started by D-C, Mar 27, 2021.

  1. D-C

    D-C pfm Member

    I'm pretty sure my Questyle CAS192D toroidal transformer has died.

    I can't turn the dac on and I'm seeing some bubbling on the outer casing of the above.

    I've tried other power leads with no sign of life, they work on the other parts of the stack.

    Any advice on this would be gratefully accepted.


  2. linnfomaniac83

    linnfomaniac83 I bet you can’t wheelie a unicycle!

    Can you upload some pictures?
  3. Marchbanks

    Marchbanks Hat and Beard member

    A shorted turn on the transformer could cause a lot of heat before dying...
  4. D-C

    D-C pfm Member

  5. booja30

    booja30 pfm Member

    Is there a fuse inside the IEC inlet, under a cap on the rear panel, or somewhere inside?
  6. D-C

    D-C pfm Member

    Oh think so, It says "only use with a 250v fuse".. that's a good sign, right?
  7. yeti42

    yeti42 pfm Member

    You can usually smell a blown transformer.
  8. Amber Audio

    Amber Audio This is the Day

  9. Jono_13

    Jono_13 Duffer

    That bubble near the centre looks wrong given how neat the rest of the wrap is....
  10. david ellwood

    david ellwood Kirabosi Kognoscente

    That might be the over temperature cutout which is normally to be found under the top few layers.

    ive never seen a transformer melted because they normally trip fuses or the thermal cutout long before they get that hot.
  11. linnfomaniac83

    linnfomaniac83 I bet you can’t wheelie a unicycle!

    That bubble does look suspect, it needs looking at. What part of the country are you in?
  12. D-C

    D-C pfm Member

    Couldn't smell anything from it on inspection.
    I agree though, that bubble is concerning to me

    Linnfo I'm down in Southend.
  13. stevec67

    stevec67 pfm Member

    Do you have a multitester and know how to check for a supply where the transformer secondaries are connected?
  14. stevec67

    stevec67 pfm Member

    Usually when transformers fail they look ok but just blow input fuses because the primary coils are shorted.
  15. D-C

    D-C pfm Member

    No multitester, or knowledge of how to check for a supply - is it easy to do if I get a multitester?
  16. D-C

    D-C pfm Member

    Have you ever been overjoyed by your own stupidity?
    Well, I have- just now.

    Left this alone for the last couple of weeks. Started testing things somewhat methodically aaand.. Yeah, t'was the plug, the fuse had gone.
    I could have sworn I tested with a different cable at the time.. clearly not.
    Anyways, no problems with the dac all working swimmingly again :D

    Thanks again to all for chipping in.
    I'll scurry off now .. into the corner with a big pointy cone on my head.
    booja30 likes this.
  17. booja30

    booja30 pfm Member

    Keep an eye on the blisters on the transformer anyway -- just in case the fuse blowing was signaling an underlying issue.
  18. D-C

    D-C pfm Member

    Will do sir, yeah, if it cuts out in spite of the change of power cable I think I'll have to get it looked at. Never missed a heart up to now though (famous last words).

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