Callsign Nomenclature
All radio stations callsigns started with ZL, although this was excluded when broadcast.
The number referred to the geographical area:
| 1 | North Island north of Taupo |
| 2 | North Island south of Taupo, Nelson and Marlborough |
| 3 | South Island north of the Waitaki River, excluding Nelson and Marlborough |
| 4 | South Island south of Waitaki River |
The first letter referred to the type of station:
| X | Private commercial stations |
| Y | Radio New Zealand non-commercial stations |
| Z | Radio New Zealand commercial stations (now The Radio Network) |
For private stations, beginning with X, the final letter in the callsign was usually the first letter of the name of the station or the name of the town the station was based in or simply a letter chosen by the station.
For non-commercial stations beginning with the letter Y, the four main centres (Auckland, Wellington, Christchurch and Dunedin) had YA stations, the second largest centre at the time was typically assigned a YZ station such as 3YZ in Greymouth and 4YZ in Southland, this was for National Radio. For other regions the final letter was typically the first letter the location. The Concert Programme in the 4 main centres was assigned YC and at this stage only broadcast in the main centres however the Concert Programme was relayed onto other stations during evenings.
The last letter was either the first letter of the location, (e.g. 1ZH in Hamilton and 4ZG in Gore) or was assigned in order with ZB going to the 4 main centres (Auckland, Wellington, Christchurch and Dunedin) and ZA going to the second largest region at the time such as 1ZA Taupo, 2ZA Palmerston North, 3ZA Greymouth and 4ZA Invercargill.
This system of allocating call signs was for AM radio stations only, the very few FM radio stations that were operating had 3 letters in the callsign, the first number remained the same. Radio stations that were originally on AM but began broadcasting on FM often kept the AM callsign name or an additional letter was added to the existing callsign name. Some examples are 2ZM in Wellington became 2ZZM (but at this point branded as ZMFM) and 1XX in Whakatane became 1XXX but remained branded as One Double X. Callsigns for these stations were often an abbreviation of the stations brand name. The FM callsigns assigned to Concert FM usually followed the format of the area number, the first letter of the city or region and then the letters CP (Concert Programme), for example 1ACP in Auckland and 4DCP in Dunedin. National Radio was not broadcasting on FM when stations were allocated callsigns so no callsigns were ever allocated to National Radio's FM frequencies.
Read more about this topic: List Of New Zealand Radio Station Callsigns