RF Cafe began life in 1996 as "RF Tools" in an AOL screen name web space totaling
2 MB. Its primary purpose was to provide me with ready access to commonly needed
formulas and reference material while performing my work as an RF system and circuit
design engineer. The World Wide Web (Internet) was largely an unknown entity at
the time and bandwidth was a scarce commodity. Dial-up modems blazed along at 14.4 kbps
while typing up your telephone line, and a nice lady's voice announced "You've Got
Mail" when a new message arrived...
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and text used on the RF Cafe website are hereby acknowledged.
Wax nostalgic about and learn from the history of early electronics. See articles
from Popular Electronics,
published October 1954 - April 1985. All copyrights are hereby acknowledged.
In 1970, engineers at the Hamilton Watch Company
introduced the world's first solid state electronic digital watch called the
Pulsar Time Computer.
It went on sale commercially two years later, just a few months after this article appeared
in the December 1971 issue of Popular Electronics magazine. Motorola created
this "$25,000 Sundial," which represents the research and development cost of the LED
clock display that the company predicted would one day lead to an inexpensive wristwatch.
Maybe they hadn't seen the The Tonight Show show where it made its debut in
1970. The Pulsar Big Time watch retailed for $295 in 1972, which in 2018 is the equivalent
of $1,777 (per the
BLS Inflation Calculator). That's about three times the cost of the
Series 4 Apple Watch today, and all the Pulsar watch could do was
tell time in the only color available until the 1980's - red.
A $25,000 Sundial?
Ever since man first became consciously aware
of the passage of time, he has attempted to segment his day by the "clock." One of the
earliest such clocks was the sundial. The desk clock shown in the photo has one thing
in common with the sundial - it contains no moving parts. This unique timepiece was built
by the Motorola Semiconductor Products Division, Central Research Laboratories, at a
developmental cost of $25,000.
The timepiece represents three departures from the conventional clock design. First,
in place of moving hands, it employs 72 light-emitting diodes (LED's) to indicate seconds,
minutes, and hours. Second, the mechanical movement has been replaced by tiny integrated
circuits that turn on the hour, minute, and second LED's. (Only three LED's are on at
any given time, allowing the clock to operate for about a year on two small batteries.)
Third, the timing device is an extremely accurate quartz crystal instead of a mechanical
tuning fork or balance staff.
Although the timepiece is only in the research phase, it is almost certain that the
electronics inside will be commercially adopted in both clocks and wrist watches before
long. Expectations are that a full integrated clock will exist within the year.
Pulsar Digital Watch Commercial
Posted October 18, 2018
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