2007 Issue 3 - Raytheon

Raytheon Acquires Percy Spencer’s Call Sign
for Homeland Security Radio Station
The Raytheon facility in Marlborough,
Mass., is currently installing an amateur
radio station to support Emergency
Operations communications. The station
will support emergency net traffic between
Raytheon facilities and also support emergency
communications with the surrounding
community. Each station will communicate
with all other Raytheon plants and/or
other amateur radio stations when the normal
lines of communication are lost — for
example, in the event of an emergency or
severe weather. The Marlborough station
will have an HF capability for long-distance
communication and a VHF capability for tieins
to local emergency management personnel
and facilities.
A call sign for the Marlborough station was
initially obtained from the FCC. Later, it was
discovered that the call sign of Raytheon’s
founder, Percy Spencer (W1GBE), was available.
It was immediately obtained as the
vanity call for the station.
Who is Percy Spencer?
Percy Spencer was an extremely competent
tube engineer and one of the company’s
founders. He was a fellow of the American
Academy of the Arts and Sciences, a member
of the Institute of Radio Engineers and
a holder of an honorary Doctor of Science
degree from the University of Massachusetts.
Above all, he was a practical engineer with
a great thirst for knowledge.
Percy Spencer, W1GBE
Percy Spencer is best remembered in
Raytheon circles for discovering a better
way to make the magnetron tube and for
inventing the microwave oven.
The Magnetron
During WWII, the British had developed an
important tube for radar called the magnetron
— a high-power S-band transmitting
tube. It was initially machined from a solid
block of copper. This was a difficult process,
and the amount of tubes made in a given
time was insufficient to keep up with
Early WWII magnatron: UX6652-13
LWWII aminated magnatron anode and
cooling fins
wartime demands. Spencer looked at the
construction of the tube and determined
that he could make the same unit by
stamping out copper sheets with the tube
cavity pattern and braze them all into
one unit in an oven. This stamped-metal
construction technique increased the
quantity of tubes made in a day from
hundreds to thousands.
Microwave Popcorn
Spencer determined that microwaves could
be used for cooking food. One day while
visiting a laboratory where magnetron
tubes were being tested, he leaned too
Special Interest
close to an open waveguide. The candy bar
in his coat pocket melted. Other scientists
had noticed this phenomenon, but Spencer
recognized its importance. Soon after, he
sent a boy out for a package of popcorn.
When the popcorn was held near a magnetron,
the popcorn exploded all around
the laboratory. Check out the artwork for
the patent application. Notice the popcorn
detailed as “food to be cooked.” Who said
engineers don’t have fun? The patent number
for this invention is 2,495,429.
The Call Sign
Percy Spencer’s grandson, Rod Spencer, was
contacted for permission to acquire and use
Percy’s call sign. He gratefully granted the
request, expressing great excitement that
his grandfather’s call sign soon would be on
the air again.
Station Status
The equipment for the radio station in
Marlborough has already been purchased.
The station will have a portable HF capability,
using a tripod-mounted HF antenna and
a fixed-station capability, using a beam
antenna. Plans are also underway to mount
the beam antenna on the facility’s roof. In
the meantime, the portable equipment may
be set up for a mock emergency.
Lou Tramontozzi, KA1HIH
Raytheon Company
Marlborough, Mass.
508.490.1236
RAYTHEON TECHNOLOGY TODAY 2007 ISSUE 3 29