I am new here and trying out 3CX for the first time, coming from using asterisk for many years. I have a Grandstream HandyTone HT503 FXO Gateway which I had working on my Asterisk system by creating a dedicated extension for it and then creating a SIP trunk to use the HT503 for inbound and outbound calls. However, I just cannot figure out how this can be done on 3CX. 3CX seems to only support a hand full of PSTN gateways. Does anyone know how I can go about using my HT503 so that I can make outbound calls through my PSTN line as well as send all inbound calls that come to my PSTN line to a certain extension or IVR? Any help would be much appreciated. Many thanks.