A FRIEND of Vaughan Savidge tried to have him paged in the RTHK canteen. After a delay, an unfamiliar voice came on the line: ''You want warm sandwich. What flavour you like?'' There the matter would normally have rested, but Savidge happens to be a writer and performer on Double Take, a 15-minute satirical show broadcast at 8.45 am every Sunday and repeated at 6.30 pm on Monday on Radio 3. Before the next session, the conversation had become the basis of a sketch in which Savidge was trying, as we all have much too frequently, to bypass a receptionist intent on forcing him, letter by painful letter, to spell out his name. ''V for Vicious, A for Angry, U for Unbelievable, G for God Almighty, H for How did you get this job? A for still angry and No for No, I'm not going to spell Savidge for you!'' Anything can provide raw material for the show, produced by Barry Bakker and scripted by Bakker, Savidge, former TVB newsman Warwick Evans and Andy Chworowsky - a team first assembled in the 1980s to dub Cantonese films into English over late night sessions. ''When you're doing a movie a night, armed with 48 cans of beer, and there's three of you playing the Korean army, you have to have a sense of humour,'' said Bakker. Halfway through its first series, Double Take is the only satirical show on Hongkong radio. Bakker rates it as a success, and he should know what it takes to make good satire. Back in the 1980s, for three consecutive years he directed an annual stage revue which became known as The 'Oids - Skitsoid, Bastoid and Paranoid. Its writers, humorists Stuart Wolfendale and Harry Rolnick included, got away with wounding the dignity of a wide variety of public figures without being sued. Double Take, which came about when Radio 3 chief Larry Ottaway put the idea to Bakker and sponsors Agfa came in, seems to be swimming against a prevailing tide in Hongkong radio towards bland, computer-selected play lists at the expense of presenters. Certainly the show pulls few punches. One of the regular items is a parody of RTHK's Barefoot Cantonese. Among the expressions suitable for doing business in Southern China have been: ''May I just say before we sign the deal that I notice you haven't gota gold wristwatch and I would like you to have mine,'' and ''No, that thousand-dollar note didn't fall out of my passport. It must belong to you or one of the other customs officers.'' Both sponsor and management have been supportive. According to Bakker, there has been no attempt to censor the programme. ''Nothing has been cut - not one inch,'' he said. ''Obviously I was worried about that. Somebody does check it every week for anything that might constitute libel, but that isn't a problem.'' Even if a degree of caution is necessary, it is generally obvious who is being got at. When, in a parody of a teacher addressing an unruly classroom, Savidge calls out: ''Miss Courtney, leave Eddington's nuts alone. You know he's sensitive about his macadamias'', the allusion is clear enough - for those in the know. ''In general we don't mention full names,'' Bakker said. ''You can mention first names. We have a character called Diane who has friends called Cristal, Chantal and Flora. I mean, they could be anybody. Oddly enough, we made her Australian, but she couldhave been Polish.'' There are taboo subjects, but Bakker maintains most subjects can be funny. He hopes to revive The 'Oids on stage, but reckons Double Take is best suited to radio rather than television. Whatever the medium, though, the rationale remains the same. ''Satire is to do with shaking people out of the stupor they can get in to, particularly in Hongkong. It's sticking a pin into inflated egos.''