Tube DIY Asylum

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RE: BDT Preamp Schematics

Posted by John Swenson on May 16, 2008 at 16:01:08:
Many different MOSFETS will work fine for Q1 and Q2. Do not substitute for the LND150s. You want enhancement mode N channel at a voltage rating that can take anything you will be throwing at it. For most tube circuits that are running under an amp of current you want to use a power mosfet designed for relatively low current, ie in the 1 amp range not the 40 amp range.

I personally have used at least six different part numbers and they all have worked fine.

John S.