'Danny's Tranny' was in The Topper between 1973 and 1986, and Roger Kettle took on the writing for a year or so.
Young Danny Wilson has a rather special tranny because pushing the different waveband buttons caused rather odd, if temporary, effects on anything that the speaker grille was pointed at.
LW (Long wave) made things grow; MW (Medium wave) made things float; SW (Short wave) made things shrink and VHF (Very High Frequency) made things invisible
We ought to point out that Danny is from the 1970's when a 'tranny' was a portable transistor radio, and had no other possible meaning....
The Topper was a UK comic published by D. C. Thomson & Co. Ltd that ran from 1953 to 1990, when it merged with The Beezer.