Chapter 1
Introduction and origins of the NBTVA
Our club was founded on two basic ideas. The first was that
television, as understood up to the mid-thirties, could be resurrected as an
interesting hobby, strictly for amateurs. The second was the belief that the
simpler mechanical scanning techniques would be within the capacity of 'kitchen
table' engineers to reproduce. Both these ideas proved to be sound.
Mechanical and low-definition TV are closely linked. In general, high-definition
mechanical cameras tended to be insensitive and the corresponding display
devices lacked brightness. The term 'mechanical' refers, of course, only to the
scanning process involved.
Early British television
Broadcasting was a produce of the advances in electronics made under military
pressure during World War I but both Baird (UK) and Jenkins (USA) had exhibited
shadows by 1923, just a year after the British Broadcasting Company was founded.
Baird demonstrated the world's first successful TV camera in January 1926 and
acquired the world's first TV transmitting licence (2TV) in 1927 but not until
September 1929 were pre-published programmes radiated by the BBC - and paid for
by the Baird company! These early programmes used a Nipkow disc flying spot
technique and were very restricted in movement.
Termed 'experimental' broadcasts, these continued till August 1932 when the BBC
took over the production of programmes with a studio in Broadcasting House. The
change involved the use of mirror drum flying spot techniques which allowed
greater movements by performers and, with a steady source of income, programmes
rapidly improved, enhanced by an auxiliary (disc) camera for captions and
superimpositions and the use of sophisticated lighting techniques. The resulting
moving pictures by 1935 represented the high point of British and probably world
television of low (less than 100 line) definition. Programmes were lively in
style and popular in content, close links having been established with London's
theatre industry. The efficacy of the video-borne sync system (the world's first)
was, however, a matter for continued debate.
Switch to all-electronic television
Regrettably, this regular service was suddenly terminated in September 1935, a
full year before the start of the daily, high-definition, all-electronic,
405-line system from Alexandra Palace, leaving thousands of 30-line receivers
useless. Commercial interest in low-definition television quickly collapsed,
speeded by the rapid appearance of high-definition receivers on the market:
seven brands and twelve models to choose from by mid-1936!
There is a little-known sequel to this story. The BBC broadcasts via their
powerful Brookman's Park transmitter reached all of Western Europe, Holland and
Denmark getting very good reception. This inspired the talented radio amateur
and Philips employee, Freek Kerkhof PA0KT, to radiate weekly Baird-standard
programmes of his own. These Sunday TV entertainments on 76 metres lasted from
1936 to 1939 when the Dutch government, fearing invasion, ordered the
confiscation of all amateur radio equipment.
Experience in other countries where low-definition TV developed (notably
Germany, France and the USA) was significantly different.
Founding of the NBTVA
The birth of our Club arose from a few concurrent events. Doug Pitt, a science
teacher in Nottingham, proposed in 1972 the building of a mechanical TV system
as an interesting project to colleague Stan Kujawinski, a keen amateur engineer.
A few months later, Doug read a "letter to the Editor" in the magazine "Wireless
World" from an Australian schoolboy, Chris Long. Chris, it became clear, had
already built a 30-line disc camera using a photomultiplier and had even put out
signals on the amateur bands with the aid of a "ham" friend. It then occurred to
Doug that there might be many other people who were thinking along the same
lines, so he placed advertisements in a number of technical magazines, inviting
correspondence. The results were immediate and soon a healthy "low definition
circle" was established and "Ideas Sheets" - single pages of suggestions -
distributed at irregular intervals.
By 1975 the circle had grown to more than forty people and a meeting was called
in April at the Clifton Training College (now Nottingham Trent University) and
attracted more than a dozen correspondents. This meeting established the "Low
Definition Television Association", open world-wide to anyone interested in the
techniques. There were only two volunteers for office, Stan Kujawinski agreeing
to be Membership Secretary & Treasurer, while Doug P. coped with other functions.
Fred Ward G2CVV agreed to be the Club's first President.
In April 1975 the first exhibition was held. This was to become an annual event.
In 1976 the first 12-page newsletter was published and in 1978 the Club's name
was changed to the present one. The club is defined as "an association of
experimenters in low definition and mechanical television".
Growth of the club
In 1981 Jeremy Jago undertook the job of dispatching the newsletters every
quarter and in 1984 also took over the printing of regular photographs. With its
committee thus strengthened, the club's membership rose rapidly and in 1993 Les
Robotham G8KLH took over Club Sales, improving matters still further.
The website, organised by Grant Dixon G8CGK (1996) represented a new departure
and was quickly dedicated to making the Club and its activities known over the
widest possible field.
Technically, the work of members has passed through a number of stages. The
earliest cameras (Long, Kujawinski, Pitt) were photomultiplier-based but after
1977 and 1978, when Dave Sumner G3PVH and Alan Short demonstrated
phototransistor-derived images, semiconductor-based cameras became the dominant
type.
In 1988 when Don McLean demonstrated a digital standard converter, a new stage
was initiated, many other converters arising over the years that followed. In
recent years, computer generation and enhancement of images have made great
strides.
The club's newsletter and website enjoy a high reputation and talks by members
are in demand. In recent years, lectures have been given, among others, to the
Society for Information Displays, the Institution of Electrical Engineers, the
British Association for the Advancement of Science, and the Royal Society.
The above, by Doug Pitt (1919-2007) is included with appreciation of his key
Club role.
The NBTVA now
Members of the NBTVA are a dedicated group of people from all walks of life
interested in the many aspects of early television. Whether it is the history,
the construction, or the computing side of the subject, NBTV has plenty to
offer.
The Narrow Band TeleVision Association is a non-profit organisation rooted in
the UK catering for people interested in all aspects of early television.
Although based in Britain it boasts a world-wide membership including Europe the
USA and Canada and as far away as New Zealand and Australia.
The club is run to promote all aspects of Narrow Band Television and presents a
forum for the exchange of ideas through a three-monthly newsletter. Technical
articles as well as news of forthcoming events, local meetings and the yearly
Convention are publicised in this journal. Aspects of the transmission and
reception of TV signals over the airwaves are also featured by our Radio Amateur
members along with timing of regular 'skeds'.
The club 'shop' featured in the newsletter provides a stock of electronic and
specialised components used in the construction of NBTV equipment for members.
Bulk purchasing avoids minimum order and carriage charges to our members as well
as providing competitive pricing.
Membership application
An application form, with details of the current membership rates, is available
from our membership secretary and treasurer Dave Gentle who can be contacted
either through e-mail or at: D.Gentle, 1 Sunny Hill, Milford, Derbyshire, DE56
0QR, England. Full details of membership and various methods of payment
including PayPal, can also be found on our website www.nbtv.org.
Please be aware that the club is not a business venture, people run the tasks
they accepted on a voluntary basis in their spare time and this should be
respected.