1n4002 diode... quick question.

Brian Marshall · May 04, 2004, 09:41:55 PM

anyone know anything about this diode off the top of their head?

im building a pt80, and it calls for one.

it is listed as a rectifier diode, so my guess is that it can handle a lot more current than a 1n914. Anywas anyone know of any easy subs.

i dont have a big diode stock. i've get lots of red and green leds, 1n914's, germanims, and schotkeys.

Brian Marshall · May 04, 2004, 09:53:59 PM

hmmm looked at the schematic, and it seems that it is just a reverse polarity protector.

anyone know the current draw?

Eric H · May 04, 2004, 10:29:14 PM

1n400X diodes are numbered in order of their breakdown voltage:
1n4001 50v
1n4002 100v
1n4004 400v
1n4007 1,000v

They are 1 amp rectifiers. They are essentially identical in low-voltage use.
Any of these will work fine, they're cheap as dirt, and there are usually several in any junk (salvage) .

HTH

-Eric

Brian Marshall · May 05, 2004, 01:43:50 AM

hmmm then i could just short it. not sure i want to do that and kill all my hard work, but it still doesnt make sense to me why it would be in there if it is acting as a fuse..... at 100v it would already be dead?!?!?

brrt · May 05, 2004, 04:08:53 AM

In your second post you said you think it's a reverse polarity protector and in your last post you want to short it? :?
So you want to connect V+ directly to GND?

I don't think it'll work :wink:

Brian Marshall · May 05, 2004, 11:26:01 AM

I dont know which it is? I have to look at the schematic again, but either way it still doesnt make much sense why they would choose this diode.

I'm at work right now, I'll look at it when i get home.

Unfortunately i have limited access to my computer at home right now.... because of my cat. Every time i get on the computer he attacks my hands trys to play. he's still a kitten and his cat box is in that room, and i dont want to lock him out. i also dont have a printer right now, so i cant print it out. i need a new cable.... which i am going to buy tonight.

Samuel · May 05, 2004, 01:39:39 PM

Are you thinking that it acts as a fuse against mains voltage? The 100V comment confused me, since no part of the PT-80 circuit ever sees more than 18...

TheBigMan · May 05, 2004, 01:46:21 PM

I looked at the PT80 schem on GGG. Sure looks like it's for reverse polarity protection to me. Most Boss and Ibanez pedals have a 1N400x around there somewhere for polarity protection. The Boss AC-2 schem I looked at for a quick ref (also on GGG) has a pair of 1N4004s at the DC jack.

It's distinctly possible that they just happened to have a bunch of them laying around. I did which is how I came to start using them to replace silicon signal diodes for clipping in distortions.

brrt · May 05, 2004, 04:29:17 PM

Why are you so interested in this diode? I looked at the PT80 schematic at generalguitargadgets and it's just a reverse polarity protector. So there's no real need to know what its breakdown voltage is or its current draw. When you reverse the polarity of the inputvoltage, the diode will have a voltagedrop of 0.7V, so the regulators won't get killed. That's all!

Brrt.

Samuel · May 05, 2004, 05:29:23 PM

I think he's looking for a possible sub?

Brian Marshall · May 05, 2004, 05:36:03 PM

Quote from: brrtWhy are you so interested in this diode? I looked at the PT80 schematic at generalguitargadgets and it's just a reverse polarity protector. So there's no real need to know what its breakdown voltage is or its current draw. When you reverse the polarity of the inputvoltage, the diode will have a voltagedrop of 0.7V, so the regulators won't get killed. That's all!

Brrt.

I want to know the current draw of the pedal, so i figure out if i can use something else with out killing the diode. example. 300 mA through 1n914= death. i was thinking about just going to radio shack and getting something close.

Paul Marossy · May 05, 2004, 06:06:35 PM

If any of the 1N400_ diodes works for 1A of current, then any one of them should work fine for your circuit. I don't think the PT-80 is going to draw 300mA of current, just looking at the schematic. But, I could be wrong...

Anytime I use a diode for polarity protection, I use at least a 1N4001. A 1N914 really is a small-signal diode, so I personally wouldn't use it in that application.

Brian Marshall · May 05, 2004, 06:12:50 PM

i knew someone was going to say that....

you think that the shack would have something i could use?

Hal · May 05, 2004, 06:33:16 PM

Yea, the rat shack deff. stocks 1n4001's...that should work...

i think they stock other rectafiers, too. $1 for a 2 pack...

and you have to buy a cell phone or they throw portable keyboards and remote control cars at you.

Paul Marossy · May 05, 2004, 06:49:14 PM

frickin' salespeople... :evil:
I bet the day is coming when they won't even sell any electonic components anymore. The world is a changin'.

Brian Marshall · May 05, 2004, 07:04:12 PM

Quote from: Paul Marossyfrickin' salespeople... :evil:
I bet the day is coming when they won't even sell any electonic components anymore. The world is a changin'.

they really have no reason to anymore. everyone orders that stuff through the internet or catlaogs now. Not really their fault.

Paul Marossy · May 05, 2004, 07:40:32 PM

Yeah, I know. It just kinda sucks. I just remember the old days when you could get all sorts of stuff from RS.

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1n4002 diode... quick question.