Re: SMPS help needed - Philips VCR

On Wed, 6 Aug 2008 14:34:17 -0700 (PDT), ajuniper@xxxxxxxxxx put
finger to keyboard and composed:

There is a short (~0.5s) squeal from the PSU when mains is applied.

I have annotated the diagram with the measured voltages (in red) and
indicated the components I have pulled and checked; the diagram can be
found at http://www.ajuniper.f2s.com/psu.jpg (2MB image).

Thanks,
Andy

Check for shorts on the secondary outputs. I'd suspect a shorted 18V
protection zener (DO15) on the AL+15V rail.

- Franc Zabkar
--
Please remove one 'i' from my address when replying by email.
.

Relevant Pages

  • Re: Component ID
    ... finger to keyboard and composed: ... but I don't remember ever encountering an SAxxx circuit ... I would think that surge arrestors should test open circuit at normal ...
    (sci.electronics.repair)
  • Re: Anti urge protector jihad!
    ... put finger to keyboard and composed: ... There is an edit in Wikipedia's Varistor article by someone posting ... as varistor energy rating is increased." ...
    (sci.electronics.repair)
  • Re: Cyber Home ADL5 DVD player, 2001
    ... finger to keyboard and composed: ... The owner seemed cagey, when I ... You should be able to test the IDE DVD loader in a PC. ...
    (sci.electronics.repair)
  • Re: Component ID
    ... finger to keyboard and composed: ... but I don't remember ever encountering an SAxxx circuit ... I would think that surge arrestors should test open circuit at normal ...
    (sci.electronics.repair)
  • Re: Cyber Home ADL5 DVD player, 2001
    ... Franc Zabkar wrote in message ... finger to keyboard and composed: ... I don't have a reference design circuit for that chip. ...
    (sci.electronics.repair)