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Projects => Tech Help - Projects Page => Topic started by: theattackman on June 01, 2010, 05:19:56 PM

Title: firebomb help (9v zener?)
Post by: theattackman on June 01, 2010, 05:19:56 PM
so it shows two diodes and for type it says 9v zener...

what is this?
Title: Re: firebomb help (9v zener?)
Post by: madbean on June 01, 2010, 05:40:03 PM
The diodes server as protection for the two transistors. Mosfets are not as stable as other types of transistors you might be familiar with, such as bi-polars, etc. The diodes basically block static discharge from the transistor in this configuration which could ruin it. You can use other types of diodes as well, such as an LED, so long as it has a high enough forward voltage.

The zener is just a type of diode. One rated at either 9v or 9.1v will work in this case.
Title: Re: firebomb help (9v zener?)
Post by: theattackman on June 01, 2010, 07:59:36 PM
so could i just put a 1n4001 in there? ???
Title: Re: firebomb help (9v zener?)
Post by: madbean on June 03, 2010, 01:37:50 PM
I can't sign off on it never having tried it, but maybe it would work well enough. In practice, I've only ever blown one mosfet in a circuit....and I think I actually had a protection diode in that case. Anyway, if you can, it's a good idea to actually socket the BS170's anyway. You will actually find very small differences in sound with each one. You might want to 'audition' some different transistors there to see which one you like best. And, since it will be socketed, should it ever blow it will be easy enough to replace.
Title: Re: firebomb help (9v zener?)
Post by: theattackman on June 11, 2010, 01:32:17 AM
so what do i put in the zener spot?

sorry im such a noob
Title: Re: firebomb help (9v zener?)
Post by: Haberdasher on June 11, 2010, 03:04:06 AM
This 1N4739A (http://www.smallbearelec.com/Detail.bok?no=330) zener from smallbear is 9.1v

I've never used one before though so it' just a guess on my part.  Anyone else know?
Title: Re: firebomb help (9v zener?)
Post by: oldhousescott on June 11, 2010, 12:59:20 PM
Quote from: Haberdasher on June 11, 2010, 03:04:06 AM
This 1N4739A (http://www.smallbearelec.com/Detail.bok?no=330) zener from smallbear is 9.1v

I've never used one before though so it' just a guess on my part.  Anyone else know?

That part should work fine.