>One good trick with any PSU cap is to put a
>resistor in series between the retifier bridge
>and the cap. This reduces startup surge current
>and increases the diode conduction time, both good
>things. Most of the commercial manufacturers use
>resistors anywhere sensitive, mainly because they
>can then use cheap weak parts and still get away
>with it. But if you use the safety resistors and
>GOOD parts you get a product that runs for 20
>years. :o)

        Don't count on that! The small kind of slot machines we found in Brazil=
 (is called "hell fire") uses a switched PSU that fails A LOT. Of course,=
 the culprit is always the (_#%**(_ safety resistor between the mains and=
 rectifier. EVERY time I get one of these to fix, the first thing I do is=
 to change the input resistor. I tried to put a resistor in series between=
 the caps and bridge, but nothing better - it just fails in about a month.=
 Bad PSU, Bad PSU :o(


---8<---Corte aqui---8<----

Alexandre Souza
taito@terra.com.br
http://planeta.terra.com.br/lazer/pinball/

---8<---Corte aqui---8<----

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