Keith Dysart wrote:
It is obvious that the power dissipated in circuilator
1 must be provided by signal generator 1 and the power
dissipated in circulator 2 must be provided by signal
generator 2.

Nope, that's not obvious at all. Make the signal generators
the same phase locked frequency with slightly different
modulation. The modulation for signal generator #1 will
appear across the load resistor in signal generator #2 and
vice versa.

A schematic shows exactly what is happening. There is no
path from SGCL1 to R1. There is no path from SGCL2 to R2.

SGCL1---1---2------2---1---SGCL2
\ / \ /
3 3
| |
R1 R2

There is nothing in the circuit to cause any reflections.
So the power dissipated in R2 comes from SGCL1 and the
power in R1 comes from SGCL2.
--
73, Cecil http://www.w5dxp.com