Callsign blocks:- JZ PK-PO YB-YH 7A-7I 8A-8I. ISO 3166 code:- IDN.OC (East Timor TMP.OC) Timezone:- Amateur Allocations are as follows:- YB = General YC = Middle YD = Novice Digit indicates area:- 0 = Djakarta 1 = Java 2 = Java 3 = Java 4 = Sumatra 5 = Sumatra 6 = Sumatra 7 = Kalimantan (Borneo) 8 = Sulawesi & Ambon 9 = Irian, Bali, Lombok and South East