Wellington Radio 1950-59

Wellington Radio ZLW in the early 1950s

The original 1912 stone building at Wellington Radio was extended and housed the station’s transmitters in the early 1950s. Courtesy Chris Underwood

Jack Colman working on a 5KW RCA transmitter at ZLW

Jack Colman working on a 5KW RCA transmitter at Wellington Radio ZLW in the early 1950s.
Courtesy Chris Underwood

The open-wire feeders from the transmitters left the building via large ceramic feedthrough insulators mounted in the small panes of glass at the top of the windows in the wall behind the transmitters. However for a time there was a central row of transmitters where the feeders went via standoff insulators mounted on the ceiling to the feedthrough insulators in the windows. The photo with Jack in it shows the feeders from the central row, hence the ceiling-mounted insulators.

An interesting feature regarding the open-wire feeders is that above each of the windows holding the feedthroughs a fluorescent tube was mounted. They were not connected to the mains in anyway but they would strike and glow brightly when the open wire feeders were carrying RF from one of the transmitters. You could see the Morse code being sent by the flashing of the tube. When I returned to the station as the Senior Tech in 1970 the open wire feeders had all been replaced by coaxial cable and at first it seemed strange without the flashing tubes although you could still hear the transmitters being keyed. You could tell a lot about the health of a transmitter by the way it sounded.

– Chris Underwood

Cartoon of Carter Observatory visitors peering through a telescope at one of the tower lights at Wellington Radio ZLW

Cartoon by Nevile Sidney Lodge in Lodge looks at Wellington, 1952, showing eager visitors to the Carter Observatory. National Library of New Zealand

1953: With the opening of Himatangi Radio, near Foxton, Wellington Radio became focused on maritime communications.1

Wellington Radio ZLW on Tinakori Hill in 1957.

Wellington Radio ZLW on Tinakori Hill in 1957. Four of the six steel lattice towers erected in 1939 can be seen. In the foreground of this photo is the circular “gridpack” antenna, aimed at Colonial Knob. This was part of a two-hop link which enabled Wellington Radio ZLW to utilise transmitters at Himatangi if one of the Tinakori Hill transmitters was out of service. Evening Post photo.

In the shed facing the camera with the large roller door (photo above) lived the notorious engine-alternator plant. During my first week on the station in 1965 I was shown this large beast – it towered over me – and I was told that in future it would be my duty to start and run it once a week for an hour to ensure that it worked. I was warned that, since an accident some years before, it had at least one slightly bent con-rod and didn’t run quite as smoothly as it should.

This was followed by instruction in how to start it. This involved first checking that the power switch for it was locked in the Test Run position. Next was starting the small petrol “donkey” engine mounted on the side of the big diesel. This engine was temperamental and on some days for no apparent reason could be quite difficult to start. Having got it to start, and having let it run for a short time to warm up, came the big moment when you connected it to the big Caterpillar diesel through a dog clutch arrangement and crossed your fingers that the donkey engine wouldn’t stall.

Normally, although the small engine literally groaned with the load, all would be well and the big “Cat” would slowly turn over a couple of times then start. It was in the days before ear protection and it was loud, but you had to stay there until it settled down. Then you could shut down the petrol engine and go out for a breath of fresh air and relative quiet.

After about an hour I had to go back and shut it down; I no longer remember the procedure for this but it was simple compared with the starting procedures. Checking the oil and fuel levels was easy but overall the weekly test run was not one of my favourite duties.

– Chris Underwood

Transmitter controls at Tinakori Hill radio station in 1957.

Transmitter controls at Wellington Radio ZLW in 1957. Evening Post photo

One normally thinks of Morse being sent on CW transmitters but the NZPO normally used MCW (Modulated CW) transmitters. The advantage of this was that if a receiving station didn’t have a proper CW receiver with a BFO, and a lot didn’t, they could more easily read the signal.
– Chris Underwood

Operators at work, Wellington Radio ZLW, 28 Oct 1957. Supervisor Austin Sumner is in the middle.

Operators at work, Wellington Radio ZLW, 28 Oct 1957. Supervisor Austin Sumner is in the middle. Evening Post photo

Working on a radio tower on Tinakori Hill in 1957.

Working on a tower at Wellington Radio ZLW in 1957. Evening Post photo

Wellington Radio Supervisor Austin Sumner places magnets representing ships on a map of the South Pacific in 1957

Wellington Radio Supervisor Austin Sumner places magnets representing ships on a map of the South Pacific in 1957. Evening Post photo

Notes:

1 Wilson, A.C. (1994). Wire and wireless: A history of telecommunications in New Zealand 1890-1987, (p 138), Palmerston North, New Zealand: Dunmore Press.

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