Focus on the South Pacific: Railway Radio 5ZB in New Zealand

(via radiodx.com)

The mobile radio broadcasting station, 5ZB, was installed into a luxury railway carriage and it made a 3 month tour of the North Island of New Zealand beginning on March 20, 1939.  The first town to host the station was Rotorua where it was involved in local civic and commercial events for a period of five days.  Mediumwave radio 5ZB radiated its locally produced live programming from a 250 watt transmitter on 1360 kHz through an antenna suspended above the railway carriage.

            The last town to host this unique radio broadcasting service was Masterton, and at the end of its third day at this location in June (1939), the station left the air; its purpose in demonstrating the value of local commercial radio broadcasting in New Zealand had been successfully achieved.  Its 2,000 miles of travel over the railway system in the North Island and its three months of service in 13 communities was over, for ever.     

            Well, as subsequent events demonstrated, not quite.  Give five months later, and the 5ZB railway carriage was on display with a majestic flourish at the Centennial Exhibition in suburban Wellington.  This Centennial Exhibition was staged in Rongotai, a specially built venue in the south eastern locality of the national capital, Wellington.  The purpose for this exhibition was to celebrate the one hundredth anniversary of the signing of a treaty between Maori leaders and the British colonial government.

            On the opening day, Wednesday November 8, 1939, 5ZB was on the air, much to the admiration of multitudes who thronged to see this unique radio broadcasting station.  The original 250 watt broadcasting transmitter was on the air again, still on its same regular channel 1360 kHz. 

            In addition, a motor van had been fitted out with a low powered shortwave transmitter for use in relaying live interviews and program segments from various remote locations back to 5ZB.  For example, on January 16 early in the new year (1940), the Exhibition welcomed its one millionth visitor, Mrs. L. D. Cogan from Dunedin.  On this occasion, the van made a shortwave broadcast back to 5ZB from a location at the gateway to the Exhibition.       

            Station 5ZB was on the air daily from its stationary location inside the Exhibition areas, usually in the afternoons and into the evenings.  Recordings were made of the 5ZB programming, including the  the shortwave spliced-in segments from nearby remote locations and these were broadcast nationwide over the network of government owned ZB commercial stations throughout New Zealand.

            A special series of remote broadcasts was planned for February 6, 1940, the exact one hundredth anniversary of the signing of the the Treaty of Waitangi.  The signing of this Treaty took place at the locality of Waitangi, which is situated on the Bay of Islands, quite near the northern tip of the North Island, nearly 500 miles north of the Exhibition location in Wellington.

            Another mobile broadcast van, normally operated by commercial station 2ZB in Wellington, was driven to Waitangi for the special anniversary broadcast.  However, this van was not equipped with a mobile shortwave transmitter, so the assistance and the equipment of three local amateur radio transmitters was called into action.

            Alan Snow of nearby Whangarei took his amateur radio equipment ZL1HJ to Waitangi for the occasion, and he relayed the anniversary celebrations on shortwave to 5ZB’s sister commercial station 1ZB in Auckland.  The input from a total of 12 microphones was spliced into this special radio programming, which was also carried by 5ZB in suburban Wellington. 

            For this special radio occasion, transmitter ZL1HJ was on the air under the callsign 1ZA, borrowed from the government operated standard mediumwave station at Whangarei.  Two other amateur stations also co-operated in this unique program relay on shortwave; Frank Hart from Paparoa with ZL1NH and Cliff McLean of Waipu with ZL1AI.

            The final day of the Centennial Exhibition in Wellington was Saturday May 4, 1940, and by this time, 2.8 million people had visited the Exhibition, considerably more than the total population of New Zealand at the time.  Radio station 5ZB was in service at this Exhibition for the entire 6 months that it was open.

            Then, radio station 5ZB was again silenced, forever.  In fact, that is not quite true either.  After the Exhibition was over, the contents of the special radio carriage AA1710 was removed and the carriage itself was returned to the New Zealand railway system for regular railway service.  In February 1982, this same carriage, though now numbered as AL50049, was written off in Auckland.                 

            However, the 5ZB transmitter was taken way down south in the South Island and it was placed in service with sister commercial station 4ZB in Dunedin where it was licensed as an auxiliary (emergency) transmitter under the callsign 4ZF.  At its new location, transmitter 4ZF was noted on occasions in New Zealand and Australia in early 1941 with test transmissions still on its regular channel of 1360 kHz.  When 4ZF got too old to be useful, it was finally silenced, for the last time. 

            However, there was an echo of this station some forty years later when another railway carriage in New Zealand was fitted out with a radio production studio, just like the old and nearly forgotten 5ZB, though no actual transmitter was installed.  The Pleasant Point Railway & Historical Society in Timaru staged the occasion in 1982 when they outfitted a Guard’s Van F423 with a bevy of electronic equipment.  Programing from this special event studio was transmitted over the nearby regular radio broadcasting station 3XC in Timaru with 2 kW on 1152 kHz.

            And that really is the end of this fascinating radio saga, a series of interesting events that spanned 43 years!

(AWR WAvescan/NWS 355)