What it is:
- 868-915Mhz Dipole PCB Antenna (50ohm)
- End-to-End length including mounting holes: 166mm
- Great performance and upgrade from the default wire monopole
- RF coax can be soldered directly to the provided pads (recommended in non modular systems - otherwise connector lengths must be taken into account when calculating feedline)
- This antenna was built on work done by forum users, see these forum threads: original design by Captcha and alternative design by ChemE
- See the RF-Best-Practices Guide on dipole and feedline length theory
What you get:
- PCB dipole antenna PCB only - see below for optional add-ons and instructions how to use it at 868Mhz/915Mhz
- SMA-female connector (not soldered). Note that you will need another SMA-female connector, to mate the other end with a Moteino or other SMA board, available separately.
- SMA-male connector, also available separately
- SMA-male cable, also available separately
The optional SMA-Male RF coax cable only mates with SMA female connectors!
You can alternatively connect SMA-male connectors directly to SMA-female connectors without a cable in between. This way you can shorten the signal path (minimize loss) and mount the dipole directly to a board, perhaps through the wall of an enclosure.
Using with 868mhz vs 915mhz:
- For 868Mhz, use this dipole as is, (78mm radiator arm lengths)
For 915Mhz, cut the arms of the antenna to 73.5mm length for maximum resonance at exactl,y 915mhz:
- the arms of the antenna are only on the TOP layer (with mm gradations) - so you have the option to just remove the copper on the TOP layer from 73mm to the edge of the PCB
- you could also cut the PCB with a strong pair of wire cutters if you need it to be shorter
- the BOTTOM layer only contains 2 pads for SMA connectors, solder this to the bottom SMA body pins for a stronger bond