Re: Lisa 1.8A Power Supply Problem

Hi Rudy,

The first thing coming to my mind is about the capacitors. I remember the same symptoms in an Apple II PS and I replaced the 2 biggest capacitors (I don't remember now the capacitance) and the problem disappeared. I remember exactly the same behavior, after something like 1 hour the computer worked again few minutes. There are ways to check the capacitors but one leg at least must be separated from the board to don't have interferences..., another possibility is to list all the capacitors and start to replace them. Look for "inflated" ones... sometimes some leakages are visible.

One thing different is that you commented about the circuit breaker in your house, it means that you have a short... Check the voltages at the output of the PS and what happens along the time, what happens during warming. Check the stability of the voltage.

The voltage regulators could be damaged....

Good luck!

Raúl

> El 02/07/2014, a las 22:30, "Rudolf Brandstötter" <R.Brandstoetter_at_email.domain.hidden> escribió:
>
> Hi guys,
>
> I have 2 1.8A PS with the same symphtom: when the PS warms up after 5-6min it shuts down. It looks like when it gets warm it does not work anymore. The circuit breaker in my house shuts down the power in the room. When the PS cools down after 1h it works again a few minutes. Do you know some typical suspects where I could look? I have a working PS as reference but I'm not really experienced in repairing PS. Thanks for any hint where to look!
>
> Rudi
> --
> --
> -----
> You received this message because you are a member of the LisaList group.
> The group FAQ is at http://lowendmac.com/lists/lisa.html
> To post to this group, send email to lisalist_at_email.domain.hidden
> To leave this group, send email to lisalist+unsubscribe_at_email.domain.hidden
> For more options, visit this group at http://groups.google.com/group/lisalist
> ---
> You received this message because you are subscribed to the Google Groups "LisaList" group.
> To unsubscribe from this group and stop receiving emails from it, send an email to lisalist+unsubscribe_at_googlegroups.com.
> For more options, visit https://groups.google.com/d/optout.

-- 
-- 
-----
You received this message because you are a member of the LisaList group.
The group FAQ is at http://lowendmac.com/lists/lisa.html
To post to this group, send email to lisalist_at_email.domain.hidden
To leave this group, send email to lisalist+unsubscribe_at_email.domain.hidden
For more options, visit this group at http://groups.google.com/group/lisalist
--- 
You received this message because you are subscribed to the Google Groups "LisaList" group.
To unsubscribe from this group and stop receiving emails from it, send an email to lisalist+unsubscribe_at_googlegroups.com.
For more options, visit https://groups.google.com/d/optout.



text/html attachment: alternate version of message