The first amateur radio operator in India was Amarendra Chandra Gooptu - callsign 2JK - licensed in 1921; later that year Mukul Bose 2HQ became the second amateur operator. By 1923 there were twenty British amateurs operating in India. The call sign prefix VU came into effect in India in 1929. There were fewer than fifty licence holders in the mid-1930's, most of them British operators in the Indian army.