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Old November 7th 07, 03:47 PM posted to rec.radio.amateur.homebrew
[email protected] francesco.messineo@gmail.com is offline
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First recorded activity by RadioBanter: Jul 2006
Posts: 40
Default BF981 classic preamp

Hi Allison,

On 7 Nov, 15:21, wrote:
On Wed, 07 Nov 2007 00:16:18 -0800,
wrote:



Hello,


On 7 Nov, 02:20, nx7u wrote:


4. The datasheet does not give any Vg2s/Id curves, and Vg1s cannot be
positive (max gate current is exceeded nearly immediately) so you're
stuck with 7mA for this part.


hmm then I surely damaged the mosfet when playing with gates
reversed.
I better find another one.


Reversing the gates wou;d not damage them. The gain would be poor
and other effects but no damage.


Hmm ok, I haven't yet desoldered the original one, I assumed it would
be bad when I read about the maximum gate current exceeded when Vg1s
is positive, which happened when I reversed the gates.


Thanks

Francesco