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Peter,
Can you please provide some details of the
Softrock mod by Jim M0BMU covering the two LF bands.
Thanks.
I am using a Softrock lite here on 500
Khz using a 4096 Khz Crystal and can confirm sensitivity
is good,
however a better
input filter maybe needed in some locations as there is some
breakthrough from strong Local Broadcast stations (Radio
Bristol) mixing with the 2nd harmonic of the LO. Ie 1548 -
(2 x 512 ) = 524 Khz = +12 Khz
In the Softrock the image is audible when
tuned to 500 Khz (-12 Khz)
73s
Jan G0BBL
----- Original Message -----
Sent: Wednesday, January 16, 2008 4:04
PM
Subject: Re: LF: LF Receiver
Hi
Laurie
It
is great to see a technical discussion on the reflector. It?s much better than
using the reflector as purely the return path of a one way VLF
qso!
I
have been using a Tony
Parks? KB9YIG Soft Rock SDR RX (about £20 kit
from WS) for some time now. I use
the excellent free SDR application software from Duncan Munro M0KGK 1.1 with
Cesco?s
HB9TLK.DLL (Loop.DLL) VAC (Virtual
Audio Cable) software link to Patrick Lindecker F6CTE?s Multpsk 4.2 decoder
software. Soft Rock does use the
IQ sound card input but this way only the one card is needed. The results are
incredible for such a small out lay. I think this setup outperforms most
conventional RX in terms of selectivity and ease of use over a limited
spectrum, 48kHz using built in soundcards and 96kHz using a high quality int
/ext Soundcard. 136 and 500 kHz
bands are only about 3 kHz wide so it gives ample coverage of the EU and US
beacon frequencies as well. Please also note that Jim Moritz M0BMU has done an
excellent mod to the current Soft rock 6.2 kit that gives these two bands as
they are not standard in the Soft rock kit
range.
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