The first Antenna I built was a quadrifilar helix (QFH) to received 137 Mhz NOAA satellites. The design is based on G4ILO's design which is based on Chris van Lint's design. Temporary location outside with a hamtronics LNK-137 preamp. As G4ILO points out on his site, this particular QFH design does not have high gain horizon to horizon, for example, my $10 2m ground plane below will receive a signal when the satellite is low in the horizon, where this QFH can not receive a signal (verified with a simple test: coax switch switching between two antennas). For someone like me, not living in an area with paging interferance, considering a different QFH design... or going with a ground plane antenna.
Experimented with just a "long wire" to improve my SWL.
Next antenna was a $10 2m ground plane made with #8 copper wire and a SO-239 socket. Shown here temporarily mounted on a ladder to receive the APRS transmissions relayed through the Internaltional Space Station (ISS) as it flew over. Currently using it as my main scanner antenna.
My next antenna is going to be a "cheap yagi" like the "435 MHz AMSAT" yagi. Planning to use this antenna to receive AMSAT satellites.
Future antenna projects will probally be more satellite focused antennas. Maybe a turnstile: