[Mare] has a visual guide and simple instructions for making DIY mini helical 868 MHz antennas for LoRa applications. 868 MHz is a license-free band in Europe, and this method yields a perfectly se… ...

The 868- and 916-MHz versions are 1/2-wave center-fed dipoles while the 315-, 418-, and 433-MHz are 1/4-wave monopoles. Price starts at $4.98 in volume. ANTENNA FACTOR, Merlin, OR. (800 ...