How do I configure a custom outbound sip call to URI

So, is it possible to setup an outbound trunk and route so that you can call ZipDX using it’s URI on a System with only PJSIP. I had done it previously by setting up a custom trunk using SIP/[email protected], and a route that calls the outbound trunk. But it doesn’t seem to work on my system, could be related to having Chan_sip turned off. I tried PJSIP/[email protected] but I get all circuits are busy.

There must be some way of making calls via URI to services like ZipDX