Antenna identification & safety


I just received my LimeSDR + antennas. I have a few questions that may be stupid but I am an SDR noob so…

  1. All the antennas appear identical. Same size, no markings. How do I know which is which? The crowdsupply page says they cover different frequency ranges. Is that wrong?

  2. If I don’t plug an antenna in is there any risk of damaging the board? I assume not for reception, but if I accidentally try to transmit without an antenna will it die?

  3. What is the difference between TX1_1 and TX1_2?


All antenna are same just cover different band base on Scott gadget antenna in his hackrf.

Sorry I don’t understand your response. Are you saying that they are all broadband antennas? They aren’t telescopic.

Broad band you change the frequency on the whip high or low.

@Ancer I think these are the right antennas.

Ah thanks that is helpful. So based on that return loss graph (which really seems to be a reflection coefficient graph) they’re fairly broadband from 900-1700 MHz and 2000-2400 MHz. Outside those ranges it has a reflection coefficient of -10 dB (i.e. 90% reflected, despite what that data sheet says). I have no experience but that seems not great.

Anyway, what about the other questions? If I transmit with no antenna will it damage the board? What’s the difference between TX1_1 and TX1_2?

I don’t think the output power of the LimeSDR would damage the board but I’m not an RF engineer. Perhaps someone with more knowledge would be able to answer this.

It always good practice to used a load when transmitting or accidentally transmitting to prevent damages on parts or rf burn.

At 10mw or less your board should be safe, but I hook up a small low power 16W dummy to mine just out of good practice.
I like my gear.