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DIY Stompboxes => Building your own stompbox => Topic started by: WGTP on March 17, 2004, 11:43:07 AM

Title: 2N7002 Mosfet
Post by: WGTP on March 17, 2004, 11:43:07 AM
Has anyone used this instead of a 2N7000 or BS170?  Is it higher gain? 8)
Title: 2N7002 Mosfet
Post by: Jered on March 17, 2004, 01:58:22 PM
Hi, isn't 2N7002 surface mount?  Jered
Title: I've never Compared them,
Post by: petemoore on March 17, 2004, 08:35:52 PM
So far I've used 2N7000 with good results
 I think the two you refferred to are listed as subs on some schematics?
 I always bias those mosfets anyway.
Title: 2N7002 Mosfet
Post by: Jered on March 18, 2004, 06:53:32 AM
Hi WG,
   Looking at the datasheet here:  http://www.fairchildsemi.com/pf/2N/2N7002.html

  It appears the 2N7002 is the surface mount equiv. of 2N7000.
  Jered
Title: 2N7002 Mosfet
Post by: WGTP on March 18, 2004, 12:29:42 PM
I thouhgt I had seen some 2N7002's in the 92 format and was looking at a spec sheet that indicated different values for the 2N7000 and 2N7002.  I don't know enough about it to determine which characteristics relate to more or less gain.  Don't remember if it was Phillips or Fairchild.  Hmmm

I was thinking a higher gain 2N7000 might come in handy for the Blue Magic/Peppermill circuits.   8)
Title: 2N7002 Mosfet
Post by: Jay Doyle on March 18, 2004, 12:57:32 PM
WG-

the 2N7002 is a surface mount 27000.

Try a BS170, it should have a good bit more gain. You are looking for transconductance, signified as gfs on datasheets. The BS170 is 320mS and the 2N7000 is 100mS. On average that is, device variation exists.
Title: 2N7002 Mosfet
Post by: GuitarLord5000 on March 18, 2004, 01:52:03 PM
How about the 7008?  Anyone have any experience with these?  A sub for the 7000 perhaps?  I've got 7000's also, but lucked out with 5 free 7008's and need something to do with them.
Title: 2N7002 Mosfet
Post by: Gringo on March 18, 2004, 02:16:43 PM
I tried 2n7008's in the multiface from ROG, and they sounded very similar to the 7000's.

Didn't fiddle too much with them either, i was just curious to see id they would work (which they did).
Title: 2N7002 Mosfet
Post by: Jay Doyle on March 18, 2004, 02:18:00 PM
Quote from: GuitarLord5000How about the 7008?  Anyone have any experience with these?  A sub for the 7000 perhaps?  I've got 7000's also, but lucked out with 5 free 7008's and need something to do with them.

See for yourself:

http://www.supertex.com/pdf/datasheets/2N7008.pdf
http://www.supertex.com/pdf/datasheets/2N7000.pdf
Title: 2N7002 Mosfet
Post by: WGTP on March 18, 2004, 03:32:24 PM
OK.  The Vishay's seem to have the same minimum value for forward transconductance for the 2N7000's and the BS170.  Thanks for the info.   8)