God of the Old Testament = YHWH
That's fine if you prefer YHWH; I only used Yahweh because that seems the preferred form of Biblical scholars.
OK, this is where the words become confusing. To the JW mind, God=Jehovah=Father. From a Trinitarian point of view, "God" is three Persons. Moreover, there have always been the Father, the Son and the Holy Spirit.
I think I understand the distinction you're explaining.
However, what I don't understand is whether there is any continuity, and if so what is it, between YHWH and the Trinitarian "God"?
Is there a direct correspondence between YHWH and any one of the persons of the Trinity, or is YHWH the same as the Godhead, all three persons of the Trinity?
Or do Trinitarians believe that the Old Testament understanding of YHWH had become outdated by the time of Jesus and was therefore replaced by Jesus or the Trinitarian "God"?
Or am I still not understanding ...?