Hi Stefan and all others.
Thank you for your most useful replies, the reasons
I asked this question are as follows, firstly I was hoping to construct one this
weekend possibly from components in my stock, a quick search on Google for
UK suppliers came up with Farnell and RS, phoned Farnell and was informed yes I
could purchase but there is a minimum order policy of £20 which equates to
about 50 BF862s, I assume that RS is the same, I also looked on Ebay non
were found. If anyone knows of a UK supplier where I could purchase say 10 ff I
would be grateful.
73s
Ken
M0KHW
----- Original Message -----
Sent: Wednesday, December 29, 2010 6:16
PM
Subject: Re: LF: DK7FC's VLF Active
Antenna
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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