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Recollections of BBC engineering from 1922 to 1997 |
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Equipment Department |
Equipment Department - the beginning By L.G.Smith** Complied and edited by Martin Ellen, from several articles written by L.G. Smith between about 1970 and 2004. E.D. and S.D.& I.D
Before the
war, there was a Station Design and Installation Department and an Equipment
Department. S.D.& I.D., under Mr MacLarty, was responsible for the planning;
design and installation of transmitters and also for the wiring and power
supplies in studio premises. The more technical aspects of the low
frequency side of broadcasting were the responsibility of Equipment Department
which had a workshop that made the items and a very small Designs Section under
Mr. Colborn. The actual number of Designs Engineers was probably about six in
1929. Broadcasting House and the studios, as far as the lighting, heating and
electrical cabling were concerned, were the responsibility of S.D. & I.D., but
the technical equipment (microphones, amplifiers, switching, control room and
studio cubicle equipment) was the responsibility of Mr. Colborn’s Designs
Section. Avenue House, Clapham – the original home of Equipment DepartmentIn 1929, 87 Kings Avenue, Clapham was the home of the BBC Research Department and Equipment Department - these departments having been formed from the single Development Department. The building was a former residence of the governor of Brixton Prison, which was within 50 yards of Avenue House. The Designs Section of Equipment Department occupied one room on the top floor. It was responsible for the design, planning and installation of the original 'grey equipment' installed in the Regional Control Rooms and in Broadcasting House. Equipment before that time had followed the Post Office practice of heavy mahogany wooden tables and desks.
The Head of
Equipment Department was F.M. Dimmock, father of Sports and OB presenter
Peter Dimmock. The only ladies on the staff were Mrs Lewis, who brought
round the tea at one old penny a cup, and a part-time cook. These two provided
two sittings of lunch in what used to be the lodge of the governor's house. All
secretaries, typists and the switchboard operators were male; one of the
switchboard operators, Holmes, in later years became Head of Research Department
drawing office at Kingswood Warren. 'Conditions of Service'Office hours were 9.30 to 6.00 and every other Saturday 9.30 to 1.00. There were no proper salary grading systems, no overtime, extra duty pay or leave in lieu; everyone worked to do a good job and many evening and all-night sessions would be worked to clear faults without thought of time off. There were 'moans'. A cost of living allowance had been paid to staff working in London at Savoy Hill and within 10 miles of Savoy Hill to cover the many premises in central London. When the headquarters moved from Savoy Hill to Broadcasting House, Avenue House was outside the 10 miles radius and the allowance was ceased.
In the economic
depression of the early 1930s a meeting was called by Sir John Reith of all BBC
staff in the Concert Hall of BH to consider a contribution by deduction from
pay, to open a centre for the unemployed in Gateshead. Equipment Department
staff, including workshop staff, came up from Avenue House and a representative
from the Ministry of Labour sat on the platform with Sir John to say his piece.
After hearing all about the project, suddenly one of the workshop staff got up
and said, "Before collecting for the unemployed in Gateshead, what about the
workshop staff at Avenue House? I have been working for the BBC for five years
and get only 6d an hour," or words to that effect. He was followed by about
half a dozen others. Sir John immediately adjourned the meeting, called for any
other complaints, took the names of the workshop staff and arranged to see them
all in his office the next morning, before continuing the meeting. As a result
many had their wages doubled and all had rises of some sort. In those days we
had a Christmas bonus equal to a week's pay, notified in a letter from Sir
John. Although a strict teetotaller, instant dismissal at the first hint of a
divorce, etc. as I understand it, he was highly esteemed by all staff. Everyone
had the right of direct access to Sir John if occasion demanded. A
head-and-shoulders engraving of him was inserted in one issue of Ariel and this
found its way to many office walls. The need for manufacturing
It is difficult
to appreciate that in the late 1920s and early 1930s virtually no commercial
equipment was available to satisfy the standards required by the BBC. Components
such as transformers, resistors, volume controls, etc. were therefore designed
and made by ED. Resistors were made by turning slots in 1-inch diameter ebonite
road and hand-winding these with resistance wire. Six such resistors about 4
inches long connected to a 24-way stud switch, also made in ED, formed a main
volume control. All components were tested before being incorporated into
amplifiers and other apparatus, which were built on 3/16-inch steel panels for
rack-mounting. Terminal blocks for these units were of 3/16- inch ebonite,
having each soldering tag fixed with a nut and bolt. Wiring inside the
units was carried out in 16SWG bare tinned copper wire covered in red sleeving
with all the wire running straight with right- angled bends. Smoking
Mr Lucking acted as liaison between the workshop and the rest of the
department. The workshops were contained in a separate brick building, the
cable-forming and bay-wiring shop consisted of a small wooden hut, which
reminded me of a seaside beach hut. The works manager, a Mr Johnson, was never
seen without the tatty end of a home made cigarette between his lips. I have a
vivid recollection of Mr Lucking, in an endeavour to cure Johnson of constant
cigarette scrounging, repacking the centre of a "Players" with crushed match
ends. Mr Johnson duly fell for the trap, which culminated in a display of
fireworks in the workshops, and no more scrounging of cigarettes from designs
section. Building at Avenue House
When the design of Broadcasting House equipment was being discussed the
provision of technical equipment required a considerable growth in the
facilities provided at Avenue House. There was adequate space in the garden,
which had a large lawn (used for cricket in the summer lunch hours) surrounded
by fruit trees. At the rear of the garage a wood and asbestos bungalow was put
up to house HED [Head of Equipment Department] and his small office staff, Mr
Colborn and Designs Section, with the Drawing Office in a long room extending
across the far end of the bungalow. Additional Designs Section staff were
recruited particularly to deal with cable forming, which was a comparatively new
idea to the BBC at that time, and the Drawing Office staff were increased to
five. Cats
This move was eagerly welcomed by the head draughtsman Allan
Holden who had a particular hate for cats, and the move brought him closer to
the high garden wall on which they used to sit. Whenever one was sighted, the
D.O. went into action with military precision, as long as "Uncle" Colborn was
not in the office! The two people on each side of the window bearing on the
line of fire, opened the window as quietly as possible. Allan then produced his
catapult, the ammunition being made from the lead sheath of a Ipr./10 cable, and
went into action. Some reduction in this activity was forced upon us when a
lady from one of the houses backing onto Avenue House garden visited H.E.D. with
some of the lead pellets and sordid stories of broken windows. Runner beans
Alan Holden lived very near Avenue House and as there was plenty of garden
available, he started a little allotment outside the drawing office windows,
which he cultivated in the evenings. He proudly announced one day that he
had planted some runner beans, so in his absence we dug up the beans and planted
instead some giant sunflower seeds, which we encouraged Alan to water every
evening. When these were about three inches high they looked very similar
to runner bean plants and Alan duly erected an array of bean sticks. At nine
inches high we persuaded him he had to tie them first clockwise and when they
still would not curl round, to try anticlockwise round each bean stick.
Alan was not a very knowledgeable gardener and it was not until the sunflower
plants were about 2ft high that Alan realised what was going on. We did,
however, enjoy a great variety of birds eating the sunflower seeds. More building and a 300-volt shock
Research Department and Equipment Department expanded still further and outgrew
the available accommodation. Research Department moved first to
Nightingale Lane and then to Nightingale Square, Clapham, and Equipment
Department expanded into the whole of Avenue House and then into a new
brick-built extension building alongside it. This extension building
housed the Test Room, with several small rooms for microphone and transformer
testing, and the Drawing Office with three Design Engineers' offices occupied a
second floor over part of the building. The only minor faults in the
design of the building were the omission of any staircase or other means of
getting to the second floor and a new patent type of parquet floor to the Test
Room. The stairs were fortunately able to be fitted in before the building was
finally occupied (although they were not wide enough to take the DO plan
chests). The Test Room floor was more serious and its fault did not come to
light till testing commenced. In those days all the equipment required Low
Tension (6 volts), High Tension and Grid Bias battery supplies, and the HT of
300 volts was available to the units under test via naked brass terminals always
fully alive at HT voltage. Safety precautions were not known in those days
and one just had to remember not to touch the bay framework when doing up the
terminal. In the new building every time anyone touched one of these terminals a
300-volt shock was received and this was traced to the floor, which although
made of wooden block set in a 'muckite' of sawdust, had a resistance of a few
hundred ohms. This fault was initially overcome by providing each engineer
with a small rubber mat to stand on. Beasties
Outside the
front door of Avenue House there stood statues of two
beasties, lion-like
creatures about 4ft high. These were originally painted all over cream but
over the years were just dirty white, until after the extension was built, when
the house was repainted by Bill Picket. He was a notable character from Building
Dept., with a real sergeant major-type waxed and pointed moustache, who was so
taken with the beasties that I think he spent more time on them than on the
house. He finished them in a dark chocolate colour with teeth and claws in
gleaming white and tongue in red. He managed to produce a most wicked look
in their eyes. So much so that one instinctively glanced over one's
shoulder when going in the door in case of attack from the rear. When Avenue
House moved to Chiswick in 1958 the beasties were moved there and put inside the
entrance hall, and I now understand they are in residence at Kingswood Warren. Drawings
Drawings at
that time were drawn in Indian ink on tracing linen. Circuits had
resistors drawn as about a dozen zigzags, all lines at the correct angle, and
transformers needed about 20 semicircles joined with straight lines to represent
the coils. All lettering was hand-done—no stencils or stick-on labels for
circuit components. Tracings then had to be taken to a firm in Kingsway for
individual prints to be made, which were in the form of white lines on a bright
blue paper—hence the term 'blueprint' used nowadays in the context of any new
National Health proposals or whatever. Later these reproductions became
dyeline prints—brown lines on white paper, much easier to mark up and revise. Test RoomHaving learnt something about ED Test Room activities by coming in on my Saturday mornings off-duty, I began working there part-time and then full-time as the workload increased with the equipment requirements for Broadcasting House and later the Regional control rooms. Although it was a long time before I was officially designated an engineer from being a drawing office tracer.
Amplifiers were
tested for frequency response by switching in a thermocouple from input to
output to measure tone from the bay-mounted variable oscillator to a fixed
oscillator mounted as far away as possible high up on the other side of the
room. Most of the time was taken up by tapping the glass of the
thermocouple meter to get as high a reading as possible. Testing microphones
We still enjoyed a few lighter moments, particularly at the expense of one
ex-Research Dept. engineer whose responsibility in Test Room was the testing of
microphones. He used a large coffin-shaped box, which had the microphone under
test at one end and a loudspeaker at the opposite end, into which tone was fed.
The box was very heavily soundproofed and the lid fitted with a very large
number of screws requiring removal for access. A headphone jack was
provided to check that the loudspeaker was working. Time after time the
diaphragms were removed from his headphones, giving him the onerous task of
removing the screws and lid to check the loudspeaker. He never seemed to learn. Battery charging
Staff Sets Section lived in a little brick building at the back of the garage
and their main occupation was battery charging, since all "wireless sets" in
those days worked from batteries. Dry batteries for H.T. and accumulators for
L.T. (To light the valves as it were). The accumulators were charged from
motor generators, although I believe someone had rigged a small arrangement
operating from the mains for "home office" accumulator charging. The whole room
presented a rather terrifying aspect to me, as a junior, with the noise and the
sparks and the smell from the acid fumes, with loose bits of wire connecting a
host of different sized accumulators in series and parallel. Carboys of acid
and distilled water and the dull glow from long sausage shaped resistance lamps. Vehicles
The garage itself possibly held about eight vehicles, the largest probably being
a one ton truck, although the main interest to staff was the ability to get
cheap petrol at I think 1/6d. a gallon from a hand operated pump. The most
notable vehicle was Mr Lucking's two sealer Morris Cowley, which was never
cleaned as he held the view that dirt protected the paint. He did at last
decide to repaint it, and started on the doors, which he took off and did a
"real Job" on them in the workshop spray booth. For many months after, the car
was to be seen with two highly polished maroon coloured doors, but the remainder
of the car as dirty as ever. Battery/mains
Up to 1938,
most of our regional premises, and Broadcasting House of course, were equipped
with apparatus operating from batteries. The only mains-operated stations
were Bangor - a small attic centre with a small control room operating from the
mains (via a large h.t. rectifier, supplied in duplicate, and l.t. rectifiers
operated from one large transformer, with an l.t. rectifier for each amplifier)
and Maida Vale which operated in a similar way. In addition there was the
training school premises in Duchess Street. These were the only equipments
working from the mains. All other premises operated from batteries charged from
mains-driven generators. Amplifier designMr. Colborn and Mr. Lock, who was Mr. Colborn*s chief assistant designer, designed some rack-mounted OBA/8 amplifiers, called APM/1s (Amplifier Programme Meter). The OBA/8 amplifier was a very versatile microphone-to-line level amplifier with a main control on it. It had a four-channel mixer, the MX/18, which went with it and was used for O.B.s. The new design made these into rack-Mounted units, providing a single output for feeding to line and a monitoring output for feeding headphones, and operating from microphone level. In order to make these usable in a control room, we needed some trap-valves, and new designs of trap-valves, TV/17 and TV/18, were devised for the purpose. This equipment had been through the drawing office, it was being made and only a very small number, if any, had actually been delivered in the summer of 1939. [See Wood Norton in the Second World War].
Regarding
trap-valve amplifiers, the TV/17 had one input and four outputs, and the TV/18
had two inputs, each having two outputs (input 1 fed outputs 1 and 2, input 2
fed outputs 3 and 4). There was rather a to-do about the labelling of
these; the circuit diagram said input 1, for instance, but when you looked at
the labelling on the amplifier it said input A, which caused considerable
confusion, especially in the designations on the jackfields. The details
of these amplifiers can be found in Technical Instruction ST.5. They used the
then ubiquitous AC/SP3 valve, and of course each had four valves, the TV/17
having one input to each of four grid circuits, and the TV/18 consisting of two
amplifiers, each with one input and two outputs. Broadcasting HouseBroadcasting House came into service in May 1932. The studios were contained in a tower built of blue engineering brick with very few doorways or other openings. This tower was surrounded by corridors and offices constructed as normal over a steel girder framework with no girder connection to the studios; thus these were well insulated from outside acoustic interference and were further insulated vertically by quiet areas such as libraries and storage areas. A fact not generally known about BH is that it has an artesian well, which provides an excellent programme earth.
The Director of
Administration at that time was of the opinion that the whole of the BBC
revolved around him and his department. Engineers were but glorified
plumbers who should be confined to the basement and the eighth floor. He
supervised the six pageboys, who sat in the entrance hall to run errands, and he
stood about in black jacket and pinstriped trousers, wearing a monocle.
One day he sent a new monocle to a small workshop attached to the eighth floor
to have it drilled for its black ribbon. As he did not specify where it
was to be drilled, it was returned to him with a single hole in the middle of
the glass. Not a person popular in the Engineering Division. Regional Control RoomsRe-equipment of the Regional Control Rooms proceeded after Broadcasting House and I was very involved in this work. In Newcastle the BBC occupied what had previously been a maternity lying-in hospital, Cardiff was done in June 1934 and occupied an old house in Park Place, and this was followed by Glasgow where the studios and Control used an old house in BIythswood Square.
Newcastle control room was originally situated on the first floor and the 'new'
control room was installed on the ground floor. Mr Colborn came up for the
handover to Mr Chadder, the Superintendent Engineer, and after demonstrating the
new relay switching and amplifiers until a late hour in the evening, since the
Post Office circuits were teed into both control rooms, Mr Colborn and Mr
Chadder put in the line fuses to the new control room, though which passed all
the programmes to the North and Scotland. They then took over control, causing
chaos upstairs and much amusement downstairs. Plugs and sockets
The only plugs and sockets available commercially were those of 5 or 15-amp, as
used for domestic power supplies, but when Broadcasting House was nearing
completion, the need arose for plugs and sockets for two specialised situations.
The first amplifier to operate directly from the mains was designed to feed the
RK loudspeaker in studio cubicles, the LSM/1, and this required plugs and
sockets for input, output and mains supply. These were designed in the
Drawing Office and I think made up in the Workshop from two-inch diameter
ebonite rod. The second application was again a purpose-designed plug and
socket used as a universal skirting socket. Although the old Reisz carbon
microphone was the standard mic., a few condenser microphones of RCA manufacture
were coming into use and these incorporated a valve amplifier, adjacent to the
microphone, which needed HT and LT supplies. (At that time it was standard
practice for all microphone or 'A' amplifiers to be located in the Control
Room.). Hence the need for an 8- pin plug to which the different
microphones could be connected, using different pins in the plug for differing
mikes. This plug, of a size unheard of in those days, was about four
inches diameter with eight pins about 1/8" diameter. It was made of
plastic and its successful introduction gave Designs Section great satisfaction. Quality
There is no doubt that the small band of engineers under Mr Colborn laid the
foundations for the high standard of BBC sound equipment and engineering.
They set a high standard of quality and freedom from interference unheard of in
the commercial world at that time. The problems of crosstalk, decoupling,
switching clicks and so on were met for the first time and their investigation
and cure involved much discussion, experiment and late night working.
There was no-one to ask who had met the problem before. There were no small
diodes and suchlike to hang in the wiring, and no electrolytic condensers.
The introduction of 25µF condensers in one fault cure I remember entailed
finding space and mechanical mounting for condensers that were about 6in x 5in x
8in high. One of these across each of a dozen relays was indeed a major
exercise. The standard 'anticlick' device was a 2µF condenser (about 2in x 2in x
lin) in tin case in series with a 600-ohm 'works wound bobbin', wired across the
coil of the relay. InstallationsSite installations were planned virtually to the last tag before site work began. All amplifiers, jacks, fuses, etc. were allocated to specific circuits and wired directly between bay tag blocks. No flexibility was provided by a distribution frame, which was only used for circuits leaving the control room. Equipment Department wiremen, under a chargehand, could therefore be sent to site with all the information, and apart from the initial and very rare supervisory visits, engineers did not visit the site until the installation was virtually complete and ready for testing. The chargehand would provide written test reports, one of which, famous for its technical content, merely stated, "I am pleased to report that the boys' colds are much better." At least it showed an awareness of the human factor in management! He was one Freddie Mott, an elderly man, very unobtrusive but a superb wireman. Every wire to a jackfield, etc., curled to exactly the same curve with a buttonhook, interbay cables laced, covered with insulating tape and finally finished with yellow empire cloth tape and never, ever, a wrong connection or a dry joint. All wiring was carried out in lead-covered 1pr/10. No multicore cables were used for programme wiring in studios or control rooms until 1940. T&D claims of the thirties make illuminating reading. Twenty-four hours' COB allowance for engineers was 16 shillings, lunch 2s 6d, evening meal 3s 6d, late night refreshment allowance for working all night 2s 6d and no compensatory leave, unsocial hours allowances or London weighting!
Testing generally started with an examination of every soldered joint for 'dry
joints' (no resin-cored solder or electric soldering irons) and a buzzer test
for continuity of the wire between its soldered terminals. After
everything had been shown to work, frequency runs were taken, not only on every
amplifier but on combinations and permutations of 'A', 'B', 'C' and 'D'
amplifiers. All these were done by switching a thermocouple between input
and output at every frequency and tapping the meter like a barometer till it
gave the highest reading. Equipment Department in the WarDuring the war, Equipment Department was split up because before the outbreak of war, it had not been considered that Design Section engineers would be used as designers, but would have assisted in the running of the broadcasting service. At the outbreak of the war they had been required to report at various transmitting stations and only Mr. Colborn and Mr, Stentiford had remained in London rebuilding the B.H. emergency control room. Although the Designs Section had been broken up, some members of it, in particular Messrs, Osmond and Trefor Williams, had gone up to Droitwich and joined S.D.I.D., who had been evacuated to Droitwich when war broke out. On 7th July 1941 I was transferred from the Wood Norton staff, where I had been an S.M.E., back to London to join Mr. Colborn's staff, who then had offices in the Langham Hotel. One or two others also came back to London, because it had become apparent that there was a very great deal of installation work required on various projects, now that the full implications of Broadcasting in wartime had been understood. I was brought back to London particularly to plan the installation of what was then known as the P.R. building, otherwise No. 200 Oxford Street. This was Peter Robinson's store that had been taken over by the BBC and was to be used for Overseas Service broadcasting. |