Question: We are doing business in Mexico and need to cure a water-based glue on 4 x 8' panels. Years ago, I successfully designed and used a microwave system to glue wooden shakes edge-to-edge to make a uniform 14" product. I believe I need a microwave energy source to accelerate the gluing process I am in charge of now. Where can I find one? - S.S.

Answer: There are a number of manufacturers worldwide who specialize in radio frequency equipment for industry. Aperiodic power units are common but suffer from frequency stability and may interfere with communication and other sensitive equipment. One way to avoid this is to use the so-called 50 Å technology systems for radio frequency. These tend to be more expensive than the conventional radio frequency systems so far used. - Ricky Metaxas, Electricity Utilization Group, acm@eng.cam.ac.uk.