City of Light: The Story of Fiber Optics

174 CITY OF LIGHT
bels. 93 All systems were go for the next step, installing a fiber-optic link to
carry live telephone traffic in the AT&T network.
The End of the Millimeter Waveguide
The wheels of progress ground more slowly for the millimeter waveguide. It
took years to prepare the test in Netcong, New Jersey, along a route planned
for a waveguide between New York and Philadelphia. Bell buried 8.7 miles
(14 kilometers) of waveguide four feet underground inside a 6-inch (15centimeter)
pipe covered with yellow plastic to protect against corrosion. Then
they filled it with nitrogen gas. Completed behind original schedule in February
1975, the installation cost $100,000 a mile. 94
Careful tests followed. Officially, Bell insisted the waveguide worked as advertised.
‘‘The verdict was that the TE 01 [waveguide] system was a success,’’
says a corporate history. ‘‘It had the predicted low losses, only 5 percent
above’’ theoretical predictions. 95 However, achieving that low loss was horrendously
difficult because minute deviations shifted energy to undesired
modes. Settling of the soil around the buried pipeline caused transmission
problems. The desired mode faded away, and new modes interfered with the
signal.
AT&T had wanted the new technology to provide tremendous capacity
over long distances. That would have justified the tremendous cost for a regulated
monopoly. By the time the test was done, the need for that extra
capacity had evaporated with the economic slump and the failure of Picturephone.
New technology packed more signals onto microwave links. 96 The
‘‘success’’ of the millimeter waveguide became academic; AT&T donated its
surplus waveguide to construction of the Very Large Array radio telescope in
Socorro, New Mexico. 97
The story was the same around the world. The British Post Office buried
14.2 kilometers (8.8 miles) of millimeter waveguide five feet under a main
road near Martlesham Heath, disrupting traffic for three months. To keep the
waveguide straight even when temperature changed, they set up equipment
to pull constantly on both ends. 98 Like Bell, the Post Office considered the
tests starting in October 1975 to be successful. 99 However, at the last minute
the Post Office canceled plans to run a millimeter waveguide from London to
Reading. Long-term monitoring of the Martlesham system showed the loss
was increasing as the soil settled. 100 The end was abrupt; research director
John Bray called the 60 or 70 people working on millimeter waveguides
together one Friday and said that on Monday they would start working on
fiber optics. 101
The millimeter waveguide was a dead duck, although the organizations
that had poured vast sums into the technology took care not to publish an
obituary. Like vanquished generals, they declared victory and retreated. Dick
Dyott never got to carry out his brash promise to run optical fibers through