nightshade,
do an internet search for "inverted L antenna".
this is a great basic antenna for SWLing, as its easy to put up, and is basically omnidirectional.
here's how i did the one i had up a few years ago.
i too used a DX-160 (great radio btw!) and was able to hear so many stations it was hard to decide what to listen to.
i used a piece of wire about 100' long.
i tied one end to a tree about 25 feet up, and strung it across my yard to another tree, securing it at the same height, i then ran the rest of the wire down the tree to the ground.
if you picture this, it looks like an upside down "L".
pound a ground rod into the ground at the base of the tree with the wire coming down, and attach the center wire of a length of coax to the wire, then attach the shield of the coax to the ground rod.
makes a great antenna.
if you're not one for climbing trees, then take a look at a "broomstick antenna".
this antenna can even be used in the house, but will work better up on your roof.
get yourself a wooden broomstick or other wooden dowel about 4 feet long.
run a length of double sided tape up the side of the broomstick.
now take a 100' roll of insulated wire and beginning at the bottom, wrap the wire neatly all the way up the broomstick. keep each turn right next to the previous one.
when you get to the top, pull out about 4-6" of wire and cut off the excess.
now get yourself an aluminum pizza dish/pie plate.
drill a hole right in the middle of it, big enough for a screw, and screw it to the top of the broomstick.
strip the wire that you wound up the broomstick and wrap it around the screw before tightening it all the way.
tighten the screw so that you have a good solid connection from the wire to the pie plate.
at the bottom of the broomstick, just leave enough wire to get from the antenna to your radio, and attach the wire to your radio.
this antenna also works surprisingly well.
good luck,
LC
...runna pile-up on 6m SSB