Tune in to early TV transmission in Queensland

by Peter Volk, Assistant Collection Manager, Social History, Queensland Museum

On 1st July 1959, nearly 60 years ago, Brisbane television station QTQ9 went on the air. A few months later, on 2nd November, ABQ2 started broadcasting as well. If you are of the right age, you can remember growing up on a steady diet of 1960’s era TV, all served in black and white, with monophonic sound, all delivered on a 576 line screen.

However, QTQ9 wasn’t the first TV station in Queensland, not by a long way. TV transmission in Queensland started on 10th April 1934, and the first TV broadcast license was issued to radio station 4CM in 1935.

What did TV look like in those days, and why did it take 25 years (!) before it became generally available?

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Nipkow DIsk and Photocell used for the first successful transmission of a television signal in Queensland on 10 April 1934. This was the heart of the TV system. The rapidly spinning disk with pinholes in the rim scanned the subject with a moving dot of light, and the “TV Eye” acted as the camera. It was a simple photocell that measured the light intensity and output a proportional electrical signal. Notice the use of cotton reels and Meccano in the construction of the supports and frame.

Experimental radio station 4CM broadcast from the convict-built Old Windmill on Wickham Terrace in Brisbane. The initial TV experiments were made late in the evening after the radio station had gone off the air. Dr Val McDowall, who owned the radio station, worked with Thomas Elliott, a local engineer and one of Queensland’s first licensed HAM radio operators, to build a TV transmitter. There were no standard components for such a thing at the time. This technology was beyond the cutting edge, so they had to improvise. The transmitter included wooden cotton reels, parts from a Meccano set and hand-cut aluminium disks. They worked with another gentleman named Alan Campbell, who went on to be a co-founder of QTQ-9. Mr Campbell had a TV receiver that was an equally home-made affair, with a screen 11 cm wide, about the size of a mobile phone screen today. Together these three men made history.

The first successful transmission of a television signal in Queensland was made on 10 April 1934, and was picked up in Mr Campbell’s home at Wilston.  The first image seen was that of Mickey Mouse, followed by a picture of actress Janet Gaynor. The first news transmission took place on 9 October 1935 with a reading from a section of a local newspaper. The first entertainment included cartoons of Mickey Mouse, and a film called “The Chocolate Soldier,” using a projector Mr Campbell had built.

The TV signal could be charitably described as low resolution. The more scan lines a TV has the better the picture is. A modern hi-definition TV has a minimum of 720 scan lines, and more commonly 1096. 4000 line (4K) TV’s are available now, and 8000 line sets (8K) are entering the market. The old B&W TVs had 576 lines. The early TV signal from 4CM’s apparatus had 30, though a later version of the equipment used a 180 line scan.

The early 30 line transmissions used a rather long radio wavelength, which gave them a good range. It was reported that 4CM had been picked up by receivers in Melbourne. Soon after, along with the shift to 180 line scans, the transmission frequency was raised. The resolution of the image was now much better, but the range was reduced to about 25 miles.

H44978.6 & 7 dThe receivers were about the size of a regular computer monitor, but most of that size went to housing the mechanical works. The actual image size was very small by comparison – from the size of a large postage stamp to the size of a mobile phone screen.

Nipkow DIsk and Photocell used for the first successful transmission of a television signal in Queensland on 10 April 1934. This was the heart of the TV system. The rapidly spinning disk with pinholes in the rim scanned the subject with a moving dot of light, and the “TV Eye” acted as the camera. It was a simple photocell that measured the light intensity and output a proportional electrical signal. Notice the use of cotton reels and Meccano in the construction of the supports and frame

This was a mechanical TV system, of the type championed and improved by John Logie Baird in the UK. The core of the TV was a spinning disk, called a Nipkow disk, with a series of holes in the rim of the disk forming a spiral. The subject was seated in near darkness, and a very bright light (usually an arc lamp) projected a pinhole sized spot of light through the holes in the rim of the Nipkow disk. The disk was spun very rapidly by an electric motor. The spacing of the holes meant that only one pinhole passed in front of the subject at a time, and the spiral pattern of the holes meant that each hole passed over a different part of the subject, moving from left to right until the whole subject had been scanned once. The wheel had then done one rotation, and on the next the subject was scanned again.

This scanning process became known as the “flying spot” technique. It was used in early broadcast TV up until 1938, in some places, and is occasionally used for specialist applications today.

Close-up view of the scanning disk. Everything was hand-built from what was available.

A photocell measured the intensity of the light reflected from the subject, and sent a signal to a second light source (usually a neon lamp) that varied in intensity according to the signal. When one looked at the second light source through a similar Nipkow disk spinning in synchronisation with the first, one saw a copy of the original signal. The trick was sending that light intensity signal to the second light source over a radio. If one can do that, one is transmitting TV. Audio was transmitted as a radio signal over a different frequency.

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It seemed that the Brisbane experimenters had the core of a successful television system. They commenced regular TV transmissions, for an hour every evening from 7:30 PM. Initially everyone had to build their own receiver from scratch, but with a bit of time and capital receivers could have been manufactured and sold to the general public. Commercial broadcasting and professionally made receivers were both available in the UK from 1929. However, the steady development and deployment of the technology was stopped dead by World War 2.

When war broke out in 1939 Australia, like the UK, withdrew all the broadcasting licenses for experimental radio and TV groups and put all their scientific efforts into military projects. The people who had been working on TV transmission had made themselves the best in Australia at cutting edge radio technology. Instead of broadcasting Mickey Mouse cartoons they found themselves working on radio and radar projects for the military. TV research went into suspension around the world – except for experiments with TV guided bombs. After the war the 4CM TV crew found that their lives had taken different directions, and the band never got back together. Additionally, mechanical TV had fallen by the wayside and been replaced by TV that used an electrically scanning cathode ray tube for the transmitter and receiver. This led to one of the first format wars, where various nations could not agree on the number of scan lines, the number of frames per second and other technical details. Australia as a whole was uncertain as to which technology to adopt. There was also dispute about how the TV industry should be organised. The British model had the government, through the BBC, running the TV stations and the U.S. model had the stations owned and run by private industry.  After much argument in Parliament the Federal Government made the firm, principled and determined choice to have five bob each way and do both. Additionally, in the early 1950’s Australia was in a recession and the capital and skills needed to develop a new industry weren’t available until later in the decade.

This early TV transmission equipment found its way to the Royal Historical Society of Queensland, and from them to the Queensland Museum, where it is preserved today. As far as is known, none of the early TV receivers have been preserved anywhere in Queensland.

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