[mythtv-users] FE replacement recommendations

[Javier Perez]

On Fri, May 29, 2009 at 11:11 AM, Brian Wood <beww at beww.org> wrote:

> On Friday 29 May 2009 09:40:21 Alan Marchiori wrote:
> > Well, I swapped out the RAM, no change.  Then I swapped the PSU and
> > low and behold it has been stable ever since.  I have been working
> > with PCs for a long time and have never seen a "bad" PSU where you
> > could still boot the machine (usually it's just dead).  It is a
> > Seasonic PSU with a 5 year warranty but they say if the fan turns on
> > the PSU is not bad (and the fan does turn on).  I guess it could have
> > been a loose connection somewhere.  I could swap it back and try to
> > fiddle with it, but I'm just happy to have my myth box working again.
>
> "If the fan turns on the PSU is not bad" is perfectly horrible advice. The
> fan
> will turn with poorly-filtered DC power, incorrect voltage and a host of
> other problems. DC motors are far less demanding in their power
> requirements
> than solid-state electronics.
>
> I'd guess you have a filter capacitor that is breaking down shortly after
> power is first applied, resulting in poorly-filtered power (an oscilloscope
> would confirm this).
>
> PSU problems that still permit the machine to boot up are really quite
> common,
> though often mis-diagnosed. Often the entire machine is replaced and the
> actual problem never discovered.
>
> The "testers" that sell for under $20 are pretty much worthless, they
> merely
> indicate the presence of the various voltages, not the accuracy or quality
> of
> the power produced. They also do not load the supply. They can reliably
> diagnose only a total failure of one or more of the rails.
>
> I'm glad you're back in business. Upgrading is always nice, but only when
> it's
> your idea.
>
> --
> beww
> beww at beww.org
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>

Hi Brian
I wonder, is there any good way to test a PSU without an oscilloscope?
I can vouch for the $20 tester not being that good.I had one that showed all
voltages
were right (i.e. the LED's would lit up) nevertheless all the problems with
the system
were solved after changing the PSU. go figure

-- 
------------------------------
/\_/\
|O O|  pepebuho at gmail.com
~~~~ Javier Perez
~~~~   While the night runs
~~~~   toward the day...
 m m   Pepebuho watches
   from his high perch.
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