Hi Ken,
I have not tested other JFETs so far. Is it just because of the SMD
housing? I don't use a SMD PCB but a "free air" soldering. So if this
is the problem, just solder the FETs legs directly on the next part,
e.g. solder the drain directly on the 390 Ohm resistor. Attached you
find a picture that shows how my current used VLF grabber antenna looks
inside. Don't be shocked ;-)
If you anyway want an alternative, the J310 or the (2SK170)
should be possible. There are some parameters like the noise and the
gain and the input capacitance which are affecting the performance but
this is all not so critical on VLF.
73, Stefan/DK7FC
Am 29.12.2010 17:58, schrieb Ken:
Stefan.
Could you please recommend an
equivalent to to BF862 which is not Surface Mount for use in this
circuit.
73s
Ken
M0KHW
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DK7FC VLF grabber antenna.JPG
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