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may not have enough rf available to energize
the meter. For many ideas see 73 's special
Antenna issue, May 1968.
As you get this set up you can think about
your transmitter. Crystal control is preferred,
so that once other QkP'ers know where your
signal typically appears on their receiver dials,
there will not be tuning questions with very
weak signals. And you will appreciate the
same reliability in their signals. On 40 meters
the best freq uencies are 7.0 I 5 or 7. 14 2
Mllz.
A typical circuit appears in Fig. 2. Few
components could be pared out of this one.
You will want to do so me experimenting with
this circuit, so start with a good high-frequency
silicon or germanium transistor, use I K
ohms in the emitter circuit, and try 82K ohms
in the base circuit. Place an mF as emitter
by-pass, and a few picofarads in the base circuit
to cont rol feedback . C3 and LI are tuned
to the o perating frequency and if LI is a
piece of Airdux, the antenna tap is easily
moved up or down. Start with the tap close
to ground, since antenna loading reduces rf
available for feedback and at some point will
cause poor keying. Listen to the signal on
your receiver.
_40'"
/~ 'Ow ;J;
Fig. 2. This could be the simplest transmitter
circuit ever published in 73 Magazine.
I nexpensfve, too . The " Joystick" antenna
i s i n the same room, eliminating co u p ler,
transm ission line, erc ., and tapping up the
co il increases loading. When you ca n get
o u t w it h this, y o u are learning to be a really
good operator.
International's printed-circuit crystal oscillator
can also do a nice job as a transmitter.
The printed-circuit co nstruction is very neat,
and the kit sets you back $2.3 5 postpaid.
See Octoher issue of 73 again, page 5. The
crystal runs another $3.75, specify the frequency.
And ano ther dollar should get the
rl well started toward the antenna.
Finishing up the rig, you put a TR switch
in the antenna system so mewhere and you
are in business. The transmitter frequency is
loca ted during tests by tuning the receiver to
pick up the transmitter- you don't do t his
with a kilowatt! with key down. The receiver
would probably not be harmed if you fed the
transmitter's entire output into its front
end and in some station setups you might
have a little difficulty finding the transmitter
signal, but a clip lead will hel p you out. Better
be careful on principle, though, if your
receiver has a solid-state front end.
Finally, start calling. It will take patience.
After all, the air is full of high-power operators,
some of whom tend to ignore signals
under S9 or so. Yours will be one of these.
Soon you will learn to operate odd hours.
Perhaps the honorable art of ragchewing will
appeal to you, again. And you will wake up
sometimes in the middle of the night thinking
about a QSO, and why not? You are
likely to become an early bird, early to bed
and early to rise. This is said to offer valuable
benefits unrelated to ham radio, and it also
gives you a fantastically quiet band to operate
in. The signals seem to sound different at
this time o f day,just before the sun is co ming
up. It is an experience you shouldn't miss.
QRP Performance and Records
Communications at ORP show a very
strong dependence upon propagation conditions.
On 40 meters, for instance, the best
results are achieved late at night, as you might
expect. But at ORP you cannot ignore the
fact s and vagaries of propagation conditions.
They just jump right out at you, and you
will soon become interested in the fluctuating
conditions of the ham bands.
Once contact is made at, say, high power
of 500 milliwatts then you can start ragchewing.
QRP contacts. unlike OX contacts,
may go on for extended periods as you and
your contact crank down the power again and
again, trying to achieve effective communication
with the smallest transmitter power input.
When your log shows you can get a 1,000
miles per watt certificate from the QRP Club
you are starting to achieve results. But the
records are very much better than that, and
recent work includes contacts on 40 met ers
ranging from 325 miles at noon to 2565 miles
at II :00 p.m., local time. On 50 milliwatts.
That's better than 50,000 miles per watt. One
million miles per watt is possible and has been
achieved. Such records are unusual and definitely
worth working for. Aside from the fact
they offer an interesting challenge of the very
best kind, you are sure to meet unusual and
interesting people along the way. Don't miss
the oppo rtunity to enjoy ORP o peratio n.
...W6TYP
MAY 1969 47