Cost estimate: $12

Here is a simple electronic alternative for those lacking space to string up 30-50 ft. of wire for reception of shortwave radio signals. The performance of this streamlined active antenna rivals that of my outdoor dipole .

Construction & Operation: Solder the electronic components on a circuit board and put it inside a small project box (be sure to leave room for the battery). Mount the switch, jack, and antenna (an 18" telescoping kind looks best, but a stiff wire will do) on the box. Attach the output to the receiver's corresponding connections and flip the switch - that's all. Keep all connections as short as possible. The diagram is pretty much self-explanatory; the only oddball part is the miniature choke. For shortwave frequencies any value around 50uH (microhenries) should perform well, but if out-of-band interference is experienced replace it with a choke of lower value. Use a higher value coil (about 470uH) for improved performance of broadcast AM radios.

..need parts?...

Covington, Michael A. N4TMI, "AM/FM/SW ACTIVE ANTENNA" 
     Popular Electronics, Vol.6, No.7, July 1989, pp.73 & 106