[sdiy] 1n4001 instead of 1n4004 OK?

[KA4HJH]

>Dan Snazelle wrote:
>> in ray wilson's +/- wallwart supply project, he asks for 1n4004
>>
>> i only have 1n4001...
>>
>> this is a 12 v psu feeding into the diode
>>
>> is this ok?
>>
>
>Yes, 1N4001 is ok up to 50V

With a 12V RMS source the *peak* potential across CR1 & 2 can reach ~34V,
depending on the charge on the filter caps. The rated voltage on the
transformer is under maximum load. With no load a "12V" transformer could
shoot up to 18V RMS or more. At that point the peak potential across the
rectifier is now close to 50V. It all depends on the transformer you
use--smaller transformers are more prone to this.

>
>But when you restock buy 1N4004 instead (or at least 1N4002).
>The cost is almost the same and then you have something you can use up
>to 400V (100V) if you need to.

Very good idea.

-- 

Terry Bowman, KA4HJH
"The Mac Doctor"