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DIY Stompboxes => Building your own stompbox => Topic started by: crawler486 on May 04, 2004, 10:51:05 AM

Title: Can a JFET sub a MOSFET?
Post by: crawler486 on May 04, 2004, 10:51:05 AM
I can't get any MOSFET transistor for the Millenium Bypass
Im building.

Can I replaced it with just a JFET?

Thanks.
Title: Can a JFET sub a MOSFET?
Post by: gez on May 04, 2004, 11:23:55 AM
You can use one of the MOSFETs in a 4007 chip (easy to come by).

Failing that, there's a JFET Millennium (the original) over at Geo.
Title: Can a JFET sub a MOSFET?
Post by: crawler486 on May 05, 2004, 01:47:44 AM
ok thanks
Title: Can a JFET sub a MOSFET?
Post by: brett on May 05, 2004, 05:36:28 AM
Hi.
Here in Oz the 2N7000 MOSFET seems more common than the BS170.

In the Millenium 2, you might try a Darlington (e.g. MPSA13/14) instead of the mosfet.  I *think* that'll work.
Title: Can a JFET sub a MOSFET?
Post by: crawler486 on May 05, 2004, 05:39:15 AM
Quote from: brettHi.
Here in Oz the 2N7000 MOSFET seems more common than the BS170.

In the Millenium 2, you might try a Darlington (e.g. MPSA13/14) instead of the mosfet.  I *think* that'll work.

wow..I hope mpsa13 works.
I got 2 lying around

thanks..
Title: Can a JFET sub a MOSFET?
Post by: Transmogrifox on May 05, 2004, 01:38:33 PM
You can usually sub most MOSFETs for MOSFETs.  Just double check your bias conditions and you'll likely be ok.

JFETs, the same.  If you know what the biases should be, you can sub.

You can also sub BJTs if you know how to change the circuit for the correct DC bias.

Any changes will likely change the sound.  MOSFET--->JFET, subtle difference, noticeable though.  FET--->BJT, likely very big change.