I am not into LW or MW but a friend who is a new SWL is.
He found two very usefull additions to his R2000 and wire antenna
setup.
http://www.kongsfjord.no/dl/Antennas/MW%20Filter%20no3.pdf

http://www.bobsamerica.com/swl
orhttp://us.geocities.com/amdxlog/index.html

The first unit was designed by Dallas is for MW but Will made some
simple changes, larger, (more inductance) colis and it works very well
down to ~100KHz. It needs some refinement for such a junp in design
frequency but it is very good at rejecting off channel RF.

The last 2, same info just different web pages by Robert Betts, work
very well as a preselctor also. While Robert uses a MMIC, I found that
Lankford "Ultra linear amplifier" to work much better as in no IMD
issues.
http://www.kongsfjord.no/dl/Amplifiers/Ultralinear%202N5109%20And%202N3053%20Amplifiers.p df
I also found that for most, 99%, an amplifier is not needed and if I
where
going to build one, I would build it test it and only add the amplifier
if needed.
Guy in the pacific NW might well use an amp, I suspect that for most of
the
rest of use the local noise floor will obviate the need for an amp.


For operation from 100KHZ through 30MHZ the Betts desing is very good.
However if onc is concentrating on MW and LF then Dallas' design is the
hands down winner. Will has both. And I thoguht I was nuts.


Will is also experimenting with Dallas' "Phaser" to allow a synthetic
steerable
antenna. Note don''t add the vernier yet, Dallas told me it might need
some
change. The basic unit is easy to build and offers excellant
performance. A
little touchy without the vernier, but a very nice unit. It even works
very well built
as a bread board.

While Dallas suggests using matched antennas, Will is using presently
mismatched
antennas, one modified North Country that consists of 2 NC singled
ended antennas
wired for dipole operation simliar to Dallas' active dipole and one
true Lankford active
dipole. There are significant differences and the NC is very prone to
overload and IMD
issues. The Lanford active dipole has no detectable IMD in from my 2
local problem
stations, 770KHz and 1240KHz. The 1240 station is 3 times as far from
me as the
770, but they sure are a good test! At some point in the near future I
hope to have
4 complete Lankford active dipoles to improve phaser performance. A set
for Will
and a set for me. I do get some grunge from LORAN C at 100KHz, but I
think that
is an receiver issue. Will is experimenting with combinations his wire
antenna
and either dipole. Every combination works, but using the 2 dipoles
works best for
him.

I am not used to being able to steer an antenna on HF to peak, or more
likeley null
RFI, a signal.

Terry