It is interesting, thanks for information and nice picture.
> Date: Wed, 11 May 2011 16:42:46 +0200
> From:
[email protected]
> To:
[email protected]
> Subject: LF: Lf Frontend
>
> Hello group,
>
> Here a picture of my new LF frontend of my active antenna,
>
http://dl.dropbox.com/u/19882028/LF/LF%20frontend.jpg
> It has a 2 stage bandpass filter in front of the first FET stage
(BF862
> which is located on the back side). The Q is not very high but DLF
and
> DCF49 are attenuated by about 15 dB. Additionally it provides a
kind of
> HV protection, i hope ;-) But the main purpose is to filter VLF
and MF
> and HF. On the older version i regularly saw MSK traces arround
136.6
> kHz. This is 153 kHz (DLF) minus 16.4 kHz (JXN)! :-)
> After some test time it moves in a water proof PVC tube now and is
> intended to run 24/7 on the grabber as the omnidirectional
antenna.
> Further improvements will be done in the shack, perhaps.
>
> 73, Stefan/DK7FC
>
