Alpha Network ADA-915-5ACM Helium Antenna 5dBi

Alpha Network ADA-915-5ACM Helium Antenna 5dBi

Purchased for $25 from Amazon here on February 8, 2022

This antenna was given a full 3D spherical swept gain test program with gain measured in over 400 physical directions and at 200 frequencies. This kind of testing helps you visualize the full radiation sphere. With normal intended installation the antenna would be vertical (the Z axis in these diagrams) with intended gain towards the horizon (from the sides of the antenna) in the XY plane.

When marketed as a 5 dBi antenna, one would expect the gain in the “sideways” directions to be approximately 5 dBi. Actual measured gain was as follows: 902 MHz +1.3 dBi; 915 MHz +0.9 dBi; 928 MHz +0.4 dBi.

While a peak gain of +2.6 dBi was measured, it was about 10 degrees above the horizon, and not really very useful. So this antenna is falling short of the expected sideways gain/directivity by about 4 dB. It is typical of consumer antennas to have over stated gains, so these results are not surprising. It is fairly small and may offer some convenience over larger outdoor antennas. The images below are all click-to-enlarge.