(hence the name ‘valve’), as a ‘rectifier’ converting AC to pulsed DC, and as
an amplifier, especially to amplify signals in radio transmitters and receivers.
Even today there are still applications that are best served by ‘valves’. For
example, in high-power short-wave transmitters, some TV transmitters, and a
special sort of valve is used in microwave transmitters for radar, and the
microwave cooker in a kitchen. Also, ask any electric guitarist about the
sound quality of a ‘valve’ amplifier.
15. Robert joined the GEC Laboratories in his mid thirties. A recently published
salary comparison (Chemistry World, December 2012, 9, 12, p. 78) suggests
that the median salary for chemists of this age at the time was about 3 times
the UK mean salary. Robert therefore would have been well remunerated in
comparative terms. For the whole of his employment at GEC the Le
Rossignols took up residence at 7 St Johns Road, Harrow, a property which
had been ‘in the family’ at least since Austen Clement’s time in London
(Chap. 1).
16. Clayton and Algar, op. cit. (note 11), p. 5.
17. A ‘getter’ is a deposit of ‘sacrificial’ reactive material that is placed inside a
lamp bulb or thermionic ‘valve’, for the purpose of completing and maintaining the vacuum. When gas molecules strike the getter material, they
combine with it chemically or by adsorption. Thus the ‘getter’ removes small
amounts of impurity gas from the evacuated space improving
filament/emitter life. The getter material was strung below the filament and
connected to the lead wires in the same way. When current first passes, the
getter immediately vapourises and is deposited on the inside of the bulb as a
small silvery metallic film. Older readers may recall this. From a Wikipedia
entry.
18. Tungsten is the most refractory metal in the periodic table and therefore an
obvious choice for a filament, but the metal is brittle and therefore difficult to
draw into a wire. Coolidge’s solution to this was to produce high purity
tungsten which was subsequently converted into an ingot by reduction
pressing and sintering. Mechanical working through a series of ‘swages’ (a
forging process in which the dimensions of an item are altered using a die or
dies, into which the item is forced) did the rest. The tungsten wires were then
as strong as steel. From, Andrea Sella, ‘Classic Kit, Coolidge’s X-ray tube’,
RSC Chemistry World, 10, 2, (February 2013), p. 62.
19. Clayton and Algar, op. cit. (note 11), p. 7.
20. Two scientific staff grades overall, Staff and Leading Staff, a situation which
was to remain until at least 1950. Clayton and Algar, op. cit. (note 11), p. 19.
21. Indeed, C. S. Le Rossignol built the first ‘all British’ ruby laser at Wembley in
the early 1960s using in-house Verneuil ‘flame fusion’ growth crystals and
xenon flash tubes made by the lamp group. Clayton and Algar, op. cit. (note
11), p. 263. Clement Sorel was born to Robert’s brother Herbert and his wife
15 The Post-war Years 1919–1930
357
an amplifier, especially to amplify signals in radio transmitters and receivers.
Even today there are still applications that are best served by ‘valves’. For
example, in high-power short-wave transmitters, some TV transmitters, and a
special sort of valve is used in microwave transmitters for radar, and the
microwave cooker in a kitchen. Also, ask any electric guitarist about the
sound quality of a ‘valve’ amplifier.
15. Robert joined the GEC Laboratories in his mid thirties. A recently published
salary comparison (Chemistry World, December 2012, 9, 12, p. 78) suggests
that the median salary for chemists of this age at the time was about 3 times
the UK mean salary. Robert therefore would have been well remunerated in
comparative terms. For the whole of his employment at GEC the Le
Rossignols took up residence at 7 St Johns Road, Harrow, a property which
had been ‘in the family’ at least since Austen Clement’s time in London
(Chap. 1).
16. Clayton and Algar, op. cit. (note 11), p. 5.
17. A ‘getter’ is a deposit of ‘sacrificial’ reactive material that is placed inside a
lamp bulb or thermionic ‘valve’, for the purpose of completing and maintaining the vacuum. When gas molecules strike the getter material, they
combine with it chemically or by adsorption. Thus the ‘getter’ removes small
amounts of impurity gas from the evacuated space improving
filament/emitter life. The getter material was strung below the filament and
connected to the lead wires in the same way. When current first passes, the
getter immediately vapourises and is deposited on the inside of the bulb as a
small silvery metallic film. Older readers may recall this. From a Wikipedia
entry.
18. Tungsten is the most refractory metal in the periodic table and therefore an
obvious choice for a filament, but the metal is brittle and therefore difficult to
draw into a wire. Coolidge’s solution to this was to produce high purity
tungsten which was subsequently converted into an ingot by reduction
pressing and sintering. Mechanical working through a series of ‘swages’ (a
forging process in which the dimensions of an item are altered using a die or
dies, into which the item is forced) did the rest. The tungsten wires were then
as strong as steel. From, Andrea Sella, ‘Classic Kit, Coolidge’s X-ray tube’,
RSC Chemistry World, 10, 2, (February 2013), p. 62.
19. Clayton and Algar, op. cit. (note 11), p. 7.
20. Two scientific staff grades overall, Staff and Leading Staff, a situation which
was to remain until at least 1950. Clayton and Algar, op. cit. (note 11), p. 19.
21. Indeed, C. S. Le Rossignol built the first ‘all British’ ruby laser at Wembley in
the early 1960s using in-house Verneuil ‘flame fusion’ growth crystals and
xenon flash tubes made by the lamp group. Clayton and Algar, op. cit. (note
11), p. 263. Clement Sorel was born to Robert’s brother Herbert and his wife
15 The Post-war Years 1919–1930
357