2 Other Needs
5 Theorical ressources
6 Technical ressources
7 Pre built antennas
∏-Box Antenna Ready to Broadcast
One Coaxial female adaptor
2 Coaxial Telescopic Antennas
Coaxial RG 174 wire
First, prepare the Wire, connect the wire to the coaxial female adaptator.
Connect the wire to the GPIO Jumper.
Add some tape.
The wire is ready, now let's make the antenna
open the coaxial T, take off the balloon, disconnect one output, break the cover of the side coaxial output.
cover it back with tape, open slightly the male plug so it can host one telescopic antenna then connect the wire.
last, connect the Antenna to the Rasperri Pi on GPIO 4 (ports 7) & GROUND (ports 9)
Ready for transmission !
Test transmission with pi-box + dipole antenna made with rigid aluminium tube
Test transmission with pi-box + dipole antenna made with flexible copper cable
Test transmission with pi-box without antenna
Test transmission with transmitter 5 watts (?) with an antenna fixed to a bike (a bike as antenna)
Build a low tech antenna with agricultural material https://www.instructables.com/id/Low-Power-FM-Transmitter-Antenna-From-Agricultural/
For example, to build a dipôle antenna for 108 MHz frequency, with 2 tubes of coper, the global lenght of the antenna will be 1389 mm, if we let 1 cm of space between the 2 tubes of coper, then each tube must mesure ~ 68,9 cm