Audiocassettes : ****Excellent ***Good **Ordinary *Poor : <i> Recent releases, reviewed by Times critics.</i>

**** “Vietnam: Radio First Termer.”

Two programs produced for National Public Radio by Interlock Media Associates. $10 each. 29 min. each. The real Adrian Cronauer, the Vietnam deejay portrayed by Robin Williams on film, is heard in an actual broadcast doing his famous, long-drawn call, “Good MORN-ing, Vietnam,” on the first of these two audio documentaries about radio’s role in the war. Snippets of broadcasts--also including Hanoi Hannah, the Tokyo Rose of her conflict--are interspersed with current interviews with veterans, among them some GIs who ran pirate stations that played the acid rock and gave the hard news censored on Armed Forces Radio. The prevalance of radios was, like the prevalence of drugs, a unique aspect of the war in Vietnam and these ambitious, deeply researched shows represent yet another aspect of the national dichotomy as it was heard and reflected in the battle zones, despite lame official attempts to erase it from the news. Information: (617) 491-3111.