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DIY Stompboxes => Building your own stompbox => Topic started by: Solidhex on March 27, 2009, 03:22:09 AM

Title: Incorporating jfet circuits into positive ground effects?
Post by: Solidhex on March 27, 2009, 03:22:09 AM
Yo

  Couldn't find any definitive info with the search function... What do you all recommend for adding Jfet buffers/boosters into positive ground effects. Wiring them upside down or finding suitable p-channel Jfets? If P-channel's the way to go what are good substitutes for the the ubiquitous j201, 2N5457, Bs-170, etc?

--Brad
Title: Re: Incorporating jfet circuits into positive ground effects?
Post by: Auke Haarsma on March 27, 2009, 04:00:27 AM
wouldn't a bi-polar powersupply do the trick?
Title: Re: Incorporating jfet circuits into positive ground effects?
Post by: Solidhex on March 27, 2009, 05:52:27 AM
Yo

  I'm aware of bipolar power supplies but I would rather know if there are positive ground versions of these circuits/components. I wouldn't want to automatically build a bipolar power supply into an effect without knowing for sure if/why I had to. Simplicity's important too I think. If you can accomplish the same task with fewer parts and signal/power routing then there's less stuff to go wrong. But if I find out there's a really good reason not to build positive ground versions of those circuits I'll go the bipolar route.

--Brad
Title: Re: Incorporating jfet circuits into positive ground effects?
Post by: Solidhex on March 27, 2009, 04:21:14 PM
Anyyyyyyooonne?

--Brad
Title: Re: Incorporating jfet circuits into positive ground effects?
Post by: MattXIV on March 27, 2009, 08:05:26 PM
I think you should be able to use them with the proper orientation (drain at higher voltage, source at lower).  The doping type of the JFET affects whether it's positive or negative voltages relative to the drain that pinch off the channel.