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Build These Timely Additions to Your Listening Post
By Ken Reitz
Anyone who becomes involved with
the radio hobby eventually becomes
obsessed with three things: radios,
antennas, and time. Radios are bought according
to budget, antennas are put up according to space,
but a clock is often an afterthought.
❖ Obsessive Clock Watchers
International shortwave broadcasters and
amateur radio nets are all concerned with time.
With two dozen time zones around the world to take
into consideration, it’s important that everyone’s
reading from the same clock. That’s why hams
and international broadcasters use one global time
standard.
Global time was originally known as Greenwich
Mean Time (GMT) because Greenwich,
England, is situated on 0° longitude, site of the
Greenwich observatory where the concept of global
time gained prominence in the world of the British
Empire. Eventually GMT became Coordinated
Universal Time which is often abbreviated as UTC
or UT. However, to save time and space it’s often
written as the letter Z and, when announced, is
said as the word “Zulu.” To beginners it may seem
confusing, but if you stay with it long enough it
eventually seems natural.
The need for a single universal time is obvious
when applied to radio. For logging shortwave radio
reception and amateur radio contacts it’s essential
to have the time correct. Whatever clocks hams
and SWLers use, they’re set to any of the world’s
time signal stations such as those of the National
Institute of Standards and Technology (NIST), formerly
known as the National Bureau of Standards,
which transmit on specified frequencies throughout
the radio spectrum (see chart).
The frequencies themselves are also a standard
and can be used to align receivers. Even the
tones transmitted are official tone standards. The
time signal clocks used by the Bureau are sophisticated
clocks with atomic based accuracy.
❖ Clock Options
An assortment of radio related clocks are
available through many mail order radio catalogs
(see list) and prices range from just a few dollars
to several thousand dollars. Thanks to the proliferation
of quartz controlled movements and liquid
crystal display (LCD) technology, an inexpensive
clock can come with all manner of extras: date
and time, 12 or 24 hour display, hour, minute
and second display, even dial lights are common.
All this can be crammed into a tiny, inexpensive,
lightweight case which can be stuck onto virtually
anything with a piece of double sided tape and
66 MONITORING TIMES January 2005
which may run for years on a watch battery.
Some radio hobbyists prefer analog clocks
which show the traditional clock face with hour,
minute and second hands. These clocks are
typically driven by a very small and very accurate
quartz movement which is usually powered by a
single AAA or AA battery. The advantage of the
analog clock is that it’s easier to read from across
the room and adds an aesthetic appeal to the radio
room.
The current rage in radio room clocks is the
so-called atomic clock which is a quartz movement
governed by an impossibly small radio receiver
Radio controlled “atomic” quartz movement
gives you unbeatable accuracy. Buy the movement
for just under $15. Build a fancy case
clock or a use a single piece of wood. (Courtesy
Klockit)
tuned to the aforementioned NIST time signal station
WWVB transmitting at 60 kHz. These clocks
are battery operated and self-adjusting. Once set,
they will continue to adjust themselves according
to changes made at the Master Clock at NIST.
These clocks also change time automatically when
the switch is made between Daylight Savings and
Standard time.
Originally expensive, these clocks are now
among the cheapest available. The technology for
these clocks has evolved to such an extent that
radio controlled wristwatches are now available at
reasonable prices. The biggest drawback to these
clocks is that they must be able to receive the time
signal and may not work well in RF unfriendly
environments such as mobile homes or large
office buildings with an abundance of steel and
concrete.
❖ Do-it-yourself Timepieces
Radio enthusiasts who enjoy home brewing
their radio gear might enjoy building their own
clocks. It’s an opportunity to be creative or customize
a time piece tailored to their own needs. There
are two sources for the would-be clock builder (see
below) who, with a few tools, a little time, and not
much money, can build his or her own radio shack
clock.
In this article I’ll show you how to build three
clocks, each requiring a different order of skill and
type of movement. I would encourage you to take
the basics of these ideas and use whatever is available
to make your own clocks. When you begin,
make a sketch with the general dimensions of the
finished clock on a piece of paper and refer to this
when planning to cut the pieces. If you don’t feel
particularly creative or lack any of the basic tools,
you might enjoy putting together any of the clock
kits which are also on the market. You can substitute
different clock works in many of the kits.
And, finally, you can customize your clock
with special brass plaques etched (available
through Klockit) with your call sign or other call
sign if you use the clock as a presentation piece
with your local radio club.
❖ The Three Piece World Time
Clock
Here’s a little desk clock which is made of
three pieces of wood. The clockworks, a Klockit
World Time insert (stock #15046), simply fits
through a hole in a piece of wood in a friction fit.
A simple top and bottom piece are glued on for a
decorative look. You can use any wood for this
project. I used some walnut scraps I had in the
wood shop, routing the edges of the top and bottom
for a more formal touch. This project works well
with wood from Lowe’s or other home building
supply house. Look in their “wood shelving” section
for finished oak, pine and poplar in a variety
of dimensions.
Using a table saw or simple hand saw, cut the
three pieces to the dimensions in your sketch. Using
a hole saw or circular cutter in a drill, cut the hole
in the upright piece of wood. If you don’t have a
drill, you can use an inexpensive coping saw and
do it by hand. Drill a small starter hole tangential
to the inside of the insert circle.
If you have a router, you can rout the three
facing edges of the top and bottom pieces for a
finished look. If you don’t have a router just skip
to the next step.
Apply glue to the top and bottom edge of
the upright piece and hold them together with
two furniture clamps. Small, cheap clamps can be
purchased at your local hardware store. Be sparing
with the glue, as dripping glue will be hard to clean
up and does not allow stain or varnish to penetrate
the wood, making an uneven appearance in the
finish.
Leave the wood in the clamps overnight to let
the glue cure. If you use a particularly nice wood
such as walnut, cherry, oak or maple, you may want