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Joined: 1/12/2009(UTC) Posts: 138 Location: London
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Hi, I initially had problems achieving enough current for Buffalo II and had to short R6. Now that I have Tridents, I need a little more, but can't get above 370mA. I'm guessing that my board had one of the low Idss JFETs. Would it be a good idea to replace the JFET or to swap pots for fixed resistors (and if so, which values of these?) or both. I'm rather low on money, so I'd rather avoid replacing it with a Placid HD if possible. Thanks. PS Would this be a suitable JFET? It has a minimum Idss of 20mA: http://cpc.farnell.com/f...-jfet-n-to-92/dp/SC12586Edited by user Saturday, January 5, 2013 6:45:30 PM(UTC)
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Rank: Member
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Joined: 1/12/2009(UTC) Posts: 138 Location: London
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Replacing the JFET with an identical one (but with higher Idss) and R6 with a 4R7 resistor did the trick. I can easily reach 450mA now. Edited by user Wednesday, January 16, 2013 10:24:29 PM(UTC)
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Rank: Administration
Groups: Administration, Customer Joined: 10/24/2006(UTC) Posts: 3,979 Location: Nashville, TN
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Sorry I missed this... but you did exactly the right thing.
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1 user thanked Russ White for this useful post.
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Rank: Member
Groups: Member
Joined: 1/12/2009(UTC) Posts: 138 Location: London
Thanks: 15 times Was thanked: 1 time(s) in 1 post(s)
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No problem Russ. It was a useful learning exercise finding the solution.
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