151
© Springer International Publishing AG, part of Springer Nature 2018
J. E. Corredor, Coastal Ocean Observing,
https://doi.org/10.1007/978-3-319-78352-9
Afterword
A short history of early steps taken to implement instrumental coastal ocean
observing using electronic means provides perspective from which to judge the
monumental advances achieved in the last century. Demand for radio telecommunications early in the last century fueled the development of electronic vacuum-tube diodes providing means to rectify AC current and triodes that could
amplify tenuous electromagnetic radio signals detected by radio antennae. Radio
antennae thus in effect constituted the first widespread commercially available
electronic sensors. The transistor invented in 1947, a solid-state device that outperformed vacuum tubes in ruggedness, energy economy, switching speed, and
bulk allowed for the development of a wide range of electronic instrument and
their miniaturization.
Perusal of texts published between 1947 and the 1970s provide a view of developments in the field. The Oceans (Sverdrup et al. 1942), a widely admired treatise
of oceanography, provides a few nuggets of information regarding the state of
electrical instrument measurements at that date. The authors quote advances in
recent years of photoelectric cells (resistance-based cadmium sulfide optical sensors), precursors to modern photodiodes for the study of seawater optical attenuation properties. Interestingly, the authors mention photronic cells but alas provide
no further reference to their nature or operation. Analog-driven quartz crystal
acoustic transducers were then already available, and various types of electromechanical current meters are mentioned providing dial displays or paper tape
recordings. Such instruments made use of Wheatstone bridges to assess current
differentials, but power amplification of such devices was restricted to vacuumtube-equipped devices.
Fifteen years later, Von Arx (1962) in his An Introduction to Physical
Oceanography mentions F. Wener’s 1922 design of a shipboard conductivity
bridge for assessing salinity used aboard coast guard vessels on the International
Ice Patrol. Von Arx further describes current meters of more recent design that
favor electrical cable both as the means of suspending the instrument and for
© Springer International Publishing AG, part of Springer Nature 2018
J. E. Corredor, Coastal Ocean Observing,
https://doi.org/10.1007/978-3-319-78352-9
Afterword
A short history of early steps taken to implement instrumental coastal ocean
observing using electronic means provides perspective from which to judge the
monumental advances achieved in the last century. Demand for radio telecommunications early in the last century fueled the development of electronic vacuum-tube diodes providing means to rectify AC current and triodes that could
amplify tenuous electromagnetic radio signals detected by radio antennae. Radio
antennae thus in effect constituted the first widespread commercially available
electronic sensors. The transistor invented in 1947, a solid-state device that outperformed vacuum tubes in ruggedness, energy economy, switching speed, and
bulk allowed for the development of a wide range of electronic instrument and
their miniaturization.
Perusal of texts published between 1947 and the 1970s provide a view of developments in the field. The Oceans (Sverdrup et al. 1942), a widely admired treatise
of oceanography, provides a few nuggets of information regarding the state of
electrical instrument measurements at that date. The authors quote advances in
recent years of photoelectric cells (resistance-based cadmium sulfide optical sensors), precursors to modern photodiodes for the study of seawater optical attenuation properties. Interestingly, the authors mention photronic cells but alas provide
no further reference to their nature or operation. Analog-driven quartz crystal
acoustic transducers were then already available, and various types of electromechanical current meters are mentioned providing dial displays or paper tape
recordings. Such instruments made use of Wheatstone bridges to assess current
differentials, but power amplification of such devices was restricted to vacuumtube-equipped devices.
Fifteen years later, Von Arx (1962) in his An Introduction to Physical
Oceanography mentions F. Wener’s 1922 design of a shipboard conductivity
bridge for assessing salinity used aboard coast guard vessels on the International
Ice Patrol. Von Arx further describes current meters of more recent design that
favor electrical cable both as the means of suspending the instrument and for