Author Topic: Testing JFETS to see if they are faulty or fake  (Read 457 times)

John S

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Testing JFETS to see if they are faulty or fake
« on: February 26, 2017, 02:33:05 PM »
How do I test jfets to see if they are faulty or fake. I tried using the greatly improved jfet matches circuit on Mark's page and they were getting really hot. Thanks
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BrianS

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Re: Testing JFETS to see if they are faulty or fake
« Reply #1 on: February 26, 2017, 02:58:26 PM »
This isn't exactly what you asked for but just info.

I mostly use SMD chips, solder them on Osh Park Jfet boards and solder legs on them.  It's a pain to do it but I don't have to worry to much about getting a fake.  If you purchase them from Smallbear, Mammoth or some place you know is reputable the likelihood of a fake is pretty slim.

These are what the Jfet board looks like:
http://www.diyguitarpedals.com.au/shop/index.php?main_page=product_info&cPath=1&products_id=286

I also use a Rullywow Jfet matcher board.  I have an extra one if you pm me your address I will send you one tomorrow, free of charge, if you're in the US. Here's a link to the matcher.

http://www.rullywow.com/jfet-matcher-project-vgsoff/