The Radio Bonnets do not have a built-in antenna. Instead, they have three options for attaching an antenna - for most low cost radio nodes, a wire works great. If you need to put the radio into an enclosure. We also include a uFL connector, pre-soldered, so you can use a uFL to SMA adapter to let you attach an external antenna. You can also solder an SMA edge-mount connector directly
A wire antenna, aka "quarter wave whip antenna" is low cost and works very well! You just have to cut the wire down to the right length.
Cut a stranded or solid core wire the the proper length for the module/frequency
- 433 MHz - 6.5 inches, or 16.5 cm
- 868 MHz - 3.25 inches or 8.2 cm
- 915 MHz - 3 inches or 7.8 cm
Strip a mm or two off the end of the wire, tin and solder into the ANT pad.
If you want an external antenna that is a few inches away from the radio, you'll want a uFL antenna. The radio bonnets have a uFL connector soldered on already - you'll also need a uFL to SMA adapter (or whatever adapter you need for the antenna you'll be using, SMA is the most common
Of course, you will also need an antenna of some sort, that matches your radio frequency. We have an antenna kit available which works well with the Radio Bonnet:
These strong edge connectors are used for many 'duck' antennas, and can also be panel mounted