Hello Graham, LF
To be honest I have not tried other feeding methods for the AD than a
trifilar 1:4 transformer. I used a beefier toroid (FT50-43) and more
turns to get a XL of 200 ohms at 400 kHz for the 50 ohm winding. The
concept of having the AD and antenna line galvanically separated and
the antenna input DC-shorted appealed to me since there is no other
protection against static.
I will give capacitor-coupling a try at some point.
A simple LPF is mandatory at least if one plans to use wire antennas,
otherwise there is a large risk of interference from VHF FM
broadcasting.
BR
Paul-Henrik, OH1LSQ
Quoting Graham <[email protected]>:
Paul,
Q , do you find the transformer feed better than , simply
connecting via a capacitor to the AD ?
73-G,
--------------------------------------------------
From: <[email protected]>
Sent: Tuesday, June 17, 2014 11:38 PM
To: <[email protected]>
Subject: Re: LF: MF CW now!
Hello Stefan, LF
Your CQ's are 539 here on a Mini-Whip directly into the
demodulator" -chip on a slightly hardware-hacked RTL-SDR TV
USB-dongle :-).
The "hack" is just bypassing the VHF/UHF tuner-chip and running
straight into the +I and -I inputs of the RTL2832U via a 1:4 XFRMR.
No TX here at the moment but receiving you so well on a hacked 10
euro USB-dongle and the old MiniWhip is just a tad more than I
expected...
BR
Paul-Henrik, OH1LSQ
Vaasa, KP03SD
Quoting DK7FC <[email protected]>:
472.2 kHz...
Anyone for a QSO?
73, Stefan
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