Take a Short Course in Shortwave

LISTENING to international broadcasts is more complicated than snapping on your kitchen radio. But any teacher can master the technical details and introduce students to shortwave. ``At first, I worried because there was so much I didn't know,'' says geography teacher Barbara Tanno of Silverdale, Wash. Now her advice to other teachers is, ``Don't be afraid. Just do it.''

Lots of help is available. Teachers can ask ham radio operators (not to be confused with less knowledgeable citizens' band enthusiasts) for assistance. To identify a ham club in your community, contact the American Radio Relay League, 225 Main St., Newington, CT 06111; telephone (203)666-1541.

``Shortwave Goes To School: A Teacher's Guide To Using Shortwave Radio in the Classroom,'' by Myles Mustoe ($26.95, including shipping), was published this year by Tiare Publications, P.O. Box 493, Lake Geneva, WI 53147.

``The World Radio TV Handbook'' (Billboard Publications, available in large bookstores) appears annually, crammed with more than 500 pages of information, including station frequencies and broadcast times in Coordinated Universal Time (UTC).

Because fewer stations are audible during daytime hours, portable receivers that students can take home overnight are recommended. Acceptable models without digital tuning cost as little as $60, Mr. Mustoe says. Digitally tuned sets suitable for classroom use start around $125.

Learning to tune a shortwave receiver is relatively simple. The more challenging tasks are deciphering the handbook, translating local time to UTC, keeping up with frequencies that may change several times a year, and coping with the vagaries of shortwave reception - which can erase even the strongest stations from the dial.

These complexities can be annoying, but they add to shortwave's value as a learning tool. Students cannot listen passively. To master the intricacies of time, frequency, and reception, they must be active learners.