Connect/solder RF pin, when using the U.FL connector?

Hi, on my own design, I am using the RAK4200 which already has the U.FL. connector on it.
I connect my external antenna there.
Do I have to take special care about the RF pin of the module?
Is this pin connected in parallel, when using the U.Fl. connector?
Shall I solder the RF Pin to my baseboard, or leave it unsoldered?

The RF Pin of the module is electrically not connected to the IPEX/ufl antenna of the module. You should not worry about your current setup. That’s ok. No need for any extra measures. You can leave the RF pin unsoldered if you want.

The RF pad is there for situations where the module has no IPEX connector on it. Since on your RAK4200 you have the IPEX connector, then that RF pad is left open and no connection internally.

Hm, I am asking because I cannot join this module, even when using same EUIs like on the RAK4200 breakoutboard, which is able to connect.
It looks like the own design is not transmitting anything into the air, as I cannot see the join request in my gateway.
As there is nothing around the module on my design, just as breakout board…
Any hints, how to check that there is something beiing sent?
Some way to turn on the carrier frequency for example?

Do you have two RAK4200 boards? One that is Breakout Board then one that is a bare Stamp Module?

The RAK4200 Breakout Board has no IPEX because it has an SMA connector. That one is working for you?

The only way to check if you have RF transmissions is by using tools like SDR or RF Explorer, etc.

Also, since you have two modules, you can try to test them on P2P mode.

Yes exaclty.
RAK with SMA is joining. Stamp with IPEX not joining.

Will investigate into P2P mode next.

Actually, if you are near your gateway, you should be able to connect with or without antenna. But I am not sure on your setup. Anyway, check P2P first then lets see. Just ensure that the configuration for both devices are the same (freq, dr, etc) then 1 should be RX and the other 1 is TX :+1: