The modernization of the seven-inch transit circle is an important aspect of the envisioned Naval Observatory observing effort. This task has been carried out on the basis of the following desiderata:

1) The basic sensor should be photoelectric

2) Point sources observable at night down to at least m=10

3) Venus, Mercury and stars down to m=4 observable in the daytime

4) Mars, Jupiter, Saturn, Uranus, Neptune and the Moon observable

5) The Sun must be observable

6) The instrumental parameters: azimuth, level, collimation, nadir, and so on must be determined so as to allow absolute observations

7) The system should operate essentially autonomously, but an observer should be kept in the observing “loop”.

It appears that all of these objectives have been achieved by the system now to be briefly described.