SMA connectors explained.

SMA and RP-SMA is well known in the world of drones, and especially in FPV systems.
But did you know that there are 4 different plugs?

You have SMA and RP-SMA and both have male and female to make it extra confusing. This could be a problem if you are new in this world and want to do some useful antenna upgrades.
I hope this post will make it a bit clear, and help you decide what kind of antenna and/or transmitter connection you need.

First a little bit of information about the naming of these plugs.

RP-SMA stands for Reverse Polarity SMA
SMA stands for Sub-Miniature Version A

Reverse polarity in this case means nothing else than the change of gender, There is no difference in use for these adapters, all are the same when it comes to video or signal quality. and the reverse polarity doesn’t tell anything about the way the signal gets transmitted!

Now about the 4 differences in the plugs.

 

As you can see in the picture the SMA male has inside thread and a male connector. You would need a SMA female on the other side

The RP-SMA male has inside thread, and a female connector, you need a RP-SMA female on the other side.
All of these difference can be very confusing.

Be aware that both antennas and connectors on the transmitter come in both SMA and RP SMA.
Different makes use different connectors.

This is an antenna with a SMA Male connector

And this is an antenna with a RP-SMA male connector


On the transmitter different connectors are possible as well.

This is a transmitter with a SMA Female connector


And this is a transmitter with a RP-SMA female connector.

If you’re planning to upgrade your FPV system, or when you need to order a new antenna  for whatever reason, take note of the connector it’s screwed on to on the transmitter side!