Building a power supply (its me again)

[MmmPedals]

building this http://tonepad.com/getFile.asp?id=111
Can I sub 4001 or 4003 for the 4002 diode? i only have 5 4002 and i need 6.

[petemoore]

  Any of those 400x diodes will work here.
 Data sheet showed different current rating II.

[JKowalski]

  Any of those 400x diodes will work here.
  Data sheet showed different current rating II.

The 1N400x series has different reverse blocking voltage ratings. 1N4001 (50v) through 1N4007 (1000v). But yes, you can use any of the 1n400x because the lowest of them is 50V and you are only dealing with 12VAC.

[PRR]

If you don't know better, use the higher-rated part.

1N4001 to 1N4007 are the same max current, but max voltage runs from 50V to 1,000V.

The 200V part will work when a 100V part is specified.

In theory you pay more for the higher-rated part.

That was true for 1N400x parts in 1973 (and back then they didn't go to 1N4007). Today they are all essentially the same price: a dime each in handfuls, 50-cent ordering onsies/twosies. Whatever small cost-difference in voltage is totally swamped by small-order stocking and handling costs. Next time you order rectifiers, get a big bag of 1N4007, and use them in all 1N400x applications.

If cost mattered.... the actual stress on the quad-bridge here is 15VAC (unloaded "12V" wart), times 1.414, divided by 2. D1-D4 need a 10V rating. D5 needs to be 11V or more. D6 needs to be 1,25V or more. You can't buy a diode rated that low. The 50V 1N4001 is ample. I assume someone speccd the '02 part because that's what they had. Even 10 years ago the '02 was a wee bit cheaper than the '07. Might still be, if you buy a million of them and negotiate the best price. But for DIY work, stock and use 1N4007 for everything.