2 Questions 1N4001,..02,..,03 Difference? / Can I find these pots anywhere

[rosssurf]

1)What is the difference from 1N4001's, 1N4002 , 03's etc.  I see people put 1N4xxx in there layouts sometimes. Obvioulsy they mean it does'nt matter which ones you use.
Is there a difference? , or at least in  pedal applications?

2) I am looking for a couple of 500K Log pots that are higher in value , like say 525 or 550. Can these be found anywhere? Or do I just need to buy a bunch and hope they are over spec?

[MartyMart]

http://www.americanmicrosemi.com/tutorials/diode.htm

1N4001/1N4002 etc are pretty much interchangeable for stompbox power protection
or for clipping diode use.
It gets more critical when using them for "stepping down" current from a mains transformer etc
as done in Amps and mains powered pre-amps.
They typically have a forward voltage drop of 1 amp
Small 1n4148's are nearer 700 milliamps and Ge 1N34A's around 300 milliamps

I've never seen that value of pot, you may get lucky and find one that's perhaps 520
or .... use some 1 meg pots and resistors to limit the range

MM

[Mark Hammer]

Um, just out of curiosity, why the need for pots just a bit higher than 500k?

[Peter Snowberg]

The 1N400x series is graded by the amount of peak inverse voltage the diode will take before breakdown. (when the magic blue smoke leaks out)

I think this is the sequence:

1N4001 = 50V
1N4002 = 100V
1N4003 = 200V
1N4004 = 400V
1N4005 = 600V
1N4006 = 800V
1N4007 = 1000V

Any will work just fine in a stompbox because the voltage is always lower than 50.

[R.G.]

2) I am looking for a couple of 500K Log pots that are higher in value , like say 525 or 550. Can these be found anywhere? Or do I just need to buy a bunch and hope they are over spec?

Pots are usually +/- 20% tolerance, so this is a good bet to be possible.

But - why?

If you know parts have a high tolerance, it's better to design so the tolerance does not matter. In this case, it would be better to change whatever the pot connects to so that you don't care if you get any pot between 400K and 600K - because you could.

Hand selecting parts sounds like mystic mojo, but it's dirty business if you have to do it more than once.

[rosssurf]

I am looking for the pot for my guitar. My luthier told me I might like the "feel" of a 500K that is over spec.

[phaeton]

I am looking for the pot for my guitar. My luthier told me I might like the "feel" of a 500K that is over spec.

Sounds like mystic mojo.

Nonetheless, as has been mentioned you can use additional resistors to tweak the ranges/extremes for pots.

[Mark Hammer]

I am looking for the pot for my guitar. My luthier told me I might like the "feel" of a 500K that is over spec.

Your luthier is partly right, but either a bit misguided or simply didn't supply you with enough info.  Lots of good info in this thread: http://www.diystompboxes.com/smfforum/index.php?topic=45916.0

[scaesic]

I am looking for the pot for my guitar. My luthier told me I might like the "feel" of a 500K that is over spec.

i wouldn't of interpretated "over spec" as "rated just over 500k", doesn't it just mean an over engineered pot?