* Use a Balun with a Dipole Antenna
Another 'improved' Shortwave Listening (SWL) Antenna
design would use a Balun {Matching Transformer} between
the Dipole Antennaand the Coax Cable feed-in-line. This
is most often a 4:1 {Four-to-One} Matching Transformer.
Using the Balun will better 'match' the Dipole Antenna to
the Coax Cable feed-in-line and the Receiver across a
wide frequency range then simply using a Dipole Antenna
that is directly connected to the Coax Cable.
- - - The direct conneted Dipole Antenna is great for Hams
working on a single Shortwave (HF) Frequency Band.

It's this balun similar to the ones used to connect 75ohm coax to the
screw connects on the back of a TV?

Brian