I have these common eBay 433 MHz module pairs pictured below and am trying to hook up an external antenna.
On the TX there is a little hole marked ANT which works for that.
On the RX pictured (XD-RF-5V), there is a similar hole with no markings that increases range if I hook it up to an antenna.
So I was looking at making dipole antennas for them, but I got confused when trying to find the ground to connect up to that part of the dipole antenna.
You might be thinking easy trace the pin marked GND, which I did, and while doing that I traced the 'antenna' hole I'm using.
The hole is connected to that little copper coil and then onto the SMD components 'above' it.
But it confuses me that there is 0 ohms resistance (as if it's connected) to that GND ground pin...
So how can it work as an antenna if it is connected to ground?
And as a second question, wouldn't I have to take into consideration the length of that coil in my antenna length calculations? What is it anyway? Could I remove it?