Neither rain nor fog nor city lights plague an avid group of undergraduate astronomers at Berkeley. They've switched from optical astronomy, telescope observations all too often washed out by street lights or obscured by clouds, to radio astronomy, tuning in to radio waves from distant objects that easily penetrate clouds and are unaffected by city lights.

To achieve this the students built an inexpensive radio telescope atop Campbell Hall, which has become the centerpiece of an innovative upper-level course in radio astronomy.

Its plywood mount and pop rivets may look low-tech, but the aluminum microwave horn, standing about 6 feet high, is equipped with high-tech electronic detectors. Costing a mere $20,000, the telescope is a testament to the ingenuity and innovation undergraduate students can bring to teaching.

"The students can see all the pieces, play with them, put them together and really understand what's going on," said senior Raghuveer Parthasarathy, who helped assemble the instrument and now is a teaching assistant for the class. "They can develop technical skills applicable to all sorts of things, not just astronomy."

Curtis Frank, who received his BS in mechanical engineering from Berkeley in 1992, and Parthasarathy, a physics and astrophysics major, discussed the philosophy behind the course June 10 at a session on college-level astronomy courses at a meeting of the American Astronomical Society in Madison, Wisc. They hope to encourage other institutions to consider radio astronomy as an educational possibility.

"We'd really like to stimulate other departments to jazz up their lab classes like this," said David Cudaback, a retired astronomy department lecturer still active in teaching the course. "Every department has a group of undergraduates that could do something on the same level as this."