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My “Career”  Part 1:   Peter J. Unwin.

I always thought that things careered downwards to an unhappy ending.  The term bothers me.  Many so called careers, after a first few years are, in reality, incredibly boring unless you are either lucky or are at the top.   I have been fortunate.  For the most part my career has been my vocation:  I have done what I wanted to do,  my work has been my hobby and as such, not work at all.  I can remember the precise moment that I knew what I wanted:  I was at KES Junior school,  thinking as I descended the stairs.  Reaching the bottom I knew…  I wanted my own company in radio or electronics.

This was my first radio.  It required a two volt accumulator to heat the filament of the valve and an HT (high tension battery) of at least 60 volts.

The valve functioned as a combined crystal set and amplifier, modulating the current from the HT battery through the headphones to reproduce the sound impressed on the radio signal

 

The next clever improvement was to add what was called a reaction control.  This fed a little of the radio signal back through the valve so that it was amplified more than once.  This made the set more sensitive, sufficient to receive amateur radio signals. Adjusting the reaction control was tricky,  too much and the set howled… and so did anyone else’s set who lived nearby and was tuned to the same station !   This could, and often did,  make me rather unpopular.

My career had begun.  I was soon reading every radio magazine and book that I could find.  One of my father’s friends gave me an old  “mains” radio and what, in its day,  was the bible of radio communications,  The Admiralty Handbook of Wireless Telegraphy Vols. 1 and 2.   I dismembered the radio and read the book again and again until I gradually began to understand it.    I wasn’t ( officially) allowed to use mains electricity so added other valves to my battery set and experimented to the point where I knew basic circuits and could devise my own according to the parts available.  I experimented with my toy morse set.   The buzzer worked like an electric bell and sparked, so could it transmit like the spark transmitters in the Admiralty handbook ?   Yes! , I could send morse code from the garden to the household radio.   Unfortunately, the neighbours also received my signals so, … in trouble again.  Eventually I was allowed to use mains electricity. I stripped other old radios and learned how to use more advanced valves to make amplifiers, radio transmitters and record-players. 

This was my first girl-friend called Billie, the youngest daughter of the farm bailiff at Wadsley Hospital. I had known Billie from the age of 4.   During the war, Wadsley Hospital, known in Sheffield as t’looney bin, accepted wounded soldiers.

My father and Joe Gillott (whose firm made pearl knives and had a nephew in my year at KES) undertook to give weekly film shows to the troops.  Father took Ward10.   This meant transporting the projector, an amplifier, loudspeaker and wind-up turntable to the ward every Monday evening by taxi.  An electric turntable would not work because the hospital ran on DC.  We had to start a rotary converter to obtain AC for the gear.  This was not stable enough to operate an electric turntable, its speed varied all the time.  Billie, her big sister, my mother and I all went along to help carry the equipment and run the wiring   They were all silent films.  Father worked the projector.  I was sometimes allowed to work the lights, play the records or even thread the film if I was lucky.   The films were hired.  Usually a feature like “Covered Wagon” and comedy such as Chaplin or Laurel & Hardy. 

So this was how I came to learn about cine projectors.  Later, father tried a sound projector which provided the basis for one of my first “inventions”.   The sound track of a film modulates a light beam. These modulations are converted to electrical modulations which amplified, are converted to sound by a loudspeaker.  If I could modulate light,  I could send sound along a light beam, but how could I do this ?   Using all the lenses I could find, I focussed light to a small spot and then into a beam.  Using an old magnetic gramophone pickup,  I worked it in reverse so that sound jiggled the needle.  Placing the needle at the focus the job was done. Unofficially borrowing the projector, I directed the beam at the photo-sensitive cell and eureka, I could send sound down a beam of light.    Easy enough with modern gear but not then;  you needed a Kerr cell… way out of my reach.  
  I experimented with chemistry and electroplating.  All chemical experiments were thrown out of the house.  I was to do them in the tool shed.   I was  coming up to the eleven plus exam and working on a further invention.  Most radios used wire aerials. Electric appliances were not suppressed.  When a near neighbour used a vacuum cleaner, it obliterated what was then the Light Programme which transmitted on the long-waveband.   I had been experimenting with two very large coils to transmit sound by magnetism and found that one of these not only worked as a aerial,  it filtered out the interference.  Most radios now use a modern version of exactly this, but much smaller … as a coil round a ferrite rod.

This is Micky Thorpe.  He was in my year at KES.  His father, a doctor, was the medical superintendent at Wadsley Hospital.   We were good boyhood friends.   Micky furthered  my education by “borrowing” .22 cartridges from his father.  We extracted the bullets andcarefully! sealed the cartridge using a vice. We then lit a fire, threw in the cartridge and retired to a safe distance.  The bang was quite dramatic. 

The picture came about because my father was setting up a photo-studio.  Lots of wives and sweethearts wanted to send pictures to the troops.   Father did the processing and enlarging at home for a while, so I learned the essentials of photography which were later to prove very valuable in my career.  We lost touch.  I believe Micky qualified in medicine.     

I was about 12 when I took the amateur radio examination.  I had the “practical” but lacked enough theory and failed. Not that this stopped me.  I built a small transmitter,  wound  up a gramophone,  ran to my grandmother’s  about 300 yards away and tuned-in to my transmission.  I now knew how to avoid interfering with commercial stations.  With this transmitter I learned the hard way what getting hold of 500 volts feels like.  I also discovered that a high voltage radio circuit can produce ozone.

I was by now building super-heterodyne receivers.  These are very different from vintage radios and much harder to construct.   In essence they are a finely adjusted radio that only works somewhere between the medium and long wave bands used for public broadcasting.  This receiver is fed from a frequency-changing circuit which converts the frequency and wavelength of a wanted signal to that of the single-frequency receiver.

My budget started to improve when neighbours discovered that I could repair their radios.  These failed quite often. Valves and electrolytic capacitors were particularly prone to failure before the Japanese taught us how to make reliable products.        

At about 13 I went for lessons in metalwork to a Mr Beal who had a home workshop equipped with a lathe, shaping machine, drill and almost any hand tool you can think of.   I started making pokers, then lens-hoods for cameras.  We tapped holes for screws and threaded with dies.   We made this enlarger from a kit of castings.  We made a bench grinder using a bicycle wheel hub for a bearing. I was taught how to sharpen lathe tools. He showed me French-polishing and how to make and wind transformers using the lathe.  My last project was a small petrol engine from a kit of castings. These had to be machined, the cylinder had to be honed and sleeved into the main casting. 

Making transformers got me into trouble.  I made one and wanted wax to impregnate the windings.  Foolishly I used candle wax,  overheating it in the chip pan.  The windings fried, candle wax vapour condensed on every cold surface in the kitchen and the chip pan was a pig to clean.

 

Mr. Beal was getting a new lathe.  My parents kindly bought Mr. Beal’s old lathe. I could now attempt something I had wanted to do for some time – record sound. 

Tape recorders were unheard of at this time.  I was friendly with Benny Brooks who was a year or so above me at King Edwards.  Benny had an 1155 ex RAF radio receiver.

Like myself, he tuned in to the radio amateurs.  We turned up a historic method of recording on steel wire.  This was hi-tech and used a little by BBC during the war.  I managed to obtain some of this wire.  Our next problems were to make the recording-head, amplifier and some means of steadily drawing the wire past the head.  The recorded signal was too weak for our home made gear.  We were saved when Baird produced a rather crude tape recorder for home movie enthusiasts.  Durex (  now Scotch ) made and sold quarter-inch wide tape.  We obtained this.  I finally managed to record sound by using a hand-cranked 8mm. re-winder used for cine film and a recording head made by cutting up a small transformer.  Voices changed pitch if you cranked faster.   Recordings could be played backwards or a toy gun made to sound like a cannon in a canyon.

Benny & I both made tape decks.  My lathe was essential for this.  The resulting reel-to-reel tape recorder was not exactly hi-fi but it worked.  We had never heard our voices recorded before.  We recorded our Band,  initially Pete Braithwaite, John Stubbs, “Bod” Jefferson, John Hunt, myself and “Mac” Davies.  Mac’s trumpet was so loud that we had to make him play outside the door.  Hunt later muted the trumpet by obstructing it with solder.  My deck was later used for what must have been one of the first rather unreliable telephone answering machines

My engineering skills were called upon when Hunt and Jefferson built a treck-cart.  Flanges were required to fit bicycle. wheels.   We had just received our O level results when the cart was trundled to the station,  loaded into the guards van and transported to Skipton to tour the Yorkshire Dales. 

Here endeth my time at KES with five O levels and not a clue how to survive in the wide world.  I was tired of school, much preferring to learn what I wanted or needed to learn from books or experience, rather than suffer any more time in any academic institution.        
My dictionary says of career : “ a racecourse, rush, progress through life or advancement in profession”  As a verb intransitive: to gallop, move or run rapidly.   Apart from progressing through life, which we all do anyway,  I don’t seem to qualify in any other way at all.     

To be continued . . . . . .

     
     
                          

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