HuwG said, "One [space elevator] on earth had to be bifurcated ('Y' shaped) near the base so that one leg was anchored in Trinidad and the other in Tobago."

Trinidad & Tobago are on a single island, about 80 km across, located about (VERY!!! roughly) 5° (five degrees) north of the equator. If the ends of a bifurcated space elevator were located both in--more or less--the same place like that they would act as a single end ... 5° OFF the equator. As it orbited it would swing through a curve from 5° north to 5° south on a 24-hour cycle. Hard to get on or off an elevator that's moving about 25 km/hr (on average).

Instead Robinson's bifurcated space telescope had one end in T&T and the other that far SOUTH of the equator. La Paz (in Bolivia), Cuiabá, or Brasilia (both in Brazil) are three possible choices. (I don't remember where Robinson had his, although I just read the trilogy a couple months ago.)

BB,
NightWing