I found this advert in the 'Perthshire Advertiser' dated 21st April 1928:
“A Dream Come True! The Gramophone that changes its own Records. HIS MASTER'S VOICE AUTOMATIC GRAMOPHONE PLAYS 20 RECORDS. SEE THIS WONDERFUL INSTRUMENT, HEAR THE PERFECT REPRODUCTION AT BLACKADDERS 202 High Street, Perth. And at 107 UNION STREET, GLASGOW.”
“A Dream Come True! The Gramophone that changes its own Records. HIS MASTER'S VOICE AUTOMATIC GRAMOPHONE PLAYS 20 RECORDS. SEE THIS WONDERFUL INSTRUMENT, HEAR THE PERFECT REPRODUCTION AT BLACKADDERS 202 High Street, Perth. And at 107 UNION STREET, GLASGOW.”