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Band plan for Japan:

5. SPLIT-FREQUENCY OPERATION







The split-frequency technique is highly recommended
for a rare DX station or DXpedition working the low bands. It
should logically also be the way we work DX on 160 meters.
Signals on Top Band are often so weak that working split
should really be the rule rather than the exception!
It is the most effective way of making as many QSOs as
possible during the short low-band openings, because the
marginal conditions often encountered are conducive to chaos
if stations are calling the DX on his frequency. It also gives a
fair chance to the stations that have the best propagation to the
DX station. With list operations this is not necessarily so, and
stations having peak propagation can bite their fingernails off
while the MC is passing along stations who barely make
contact and have to fight to get a 33 report. With split opera­
tion the DXer with a good antenna and with good operating
practice is bound to have a lead over the modest station. This
is only fair. Why else would we build a station that performs
better than the average?
There are two good reasons for the DX station to work
split frequency:
1. First he must realize that when he stops his CQ, there are
likely to be many stations calling him. Though he might
pick out a good strong signal, others may still call him,
and his reply to a particular station may be lost in the
QRM. This will result in a slow QSO rate, even though
the DX station hears the callers well. If he works split, the
callers will have more chance to get the DX’s reply right
the first time. The reason here is obviously that callers
cannot cope with the QRM they are creating themselves
on the DX’s frequency. In this case the DX station should
simply specify a single frequency (eg, up 5) where he will
be listening.
2. Another reason is that there are such large numbers of
stations calling the DX station that the DX cannot dis­
criminate the callers. In this case it is the DX station that
will not be able to handle the situation without going
split. In this case he will specify a frequency range where
he will be listening, in order to spread out the callers, and
make the layer less thick.

3500 to 3520 CW only
3520 to 3525 Digital modes and CW
3525 to 3575 All modes
3747 to 3754 kHz All modes
3791 to 3805 kHz All modes

Band plan for the USA:
Since the FCC decided to expand SSB privileges in the
US, first to 3775 and later to 3750 kHz for Extra-Class
amateurs, the DX window has de facto expanded from below
3750 to 3800 kHz during openings to the US, although the top
25 kHz is the focal area.

4.3.2.2. Recommendations for 80 meters
Many amateurs are unaware that 80 meters is a shared
band in many parts of the world. In the USA, 80 meters sounds
like a quiet VHF band compared to what it sounds like in
Europe. Because of the many commercial stations on the band
in Europe, the 25-kHz DX window can often hold only five
QSOs in-between the extremely strong commercial stations
in the local evening hours. If you are fortunate enough to live
in a region where 80 meters is either exclusive or not heavily
used by commercial stations, please be aware of this and bear
with those who must continuously fight the commercial QRM.
Fortunately there is a common (IARU) DX window in
Regions 1 and 2, but this is not enforced and is not respected
by all. US stations complain bitterly about poor cooperation
from rag chewers (“pig farmers” as they’re sometimes called
in the US), who have another 200 kHz that could be used for
their local contacts.
The increased popularity of 80-meter DXing, together
with the few DX channels available in the phone DX window,
have created a problem where certain individuals would sit on
a frequency in the DX window for hours (it seems like days)
on end, without giving anyone else a chance. This problem is
nonexistent on CW, where you have an abundance of DX
channels in the DX window. This situation is also an excuse
for creating DX nets, where ethics are not always the highest.
4.3.3. Let’s be practical on 40 meters
Forty meters is pretty straightforward. CW DX QSOs all
happen between 7000 and 7010 kHz, with rare exceptions
around 7025 kHz. Although no formal DX subband has been
created by IARU, the 7000 to 7010-kHz window is the defacto
DX subband on 40 meters.
In the European or non-US phone band, being as narrow
as it is, you can find DX anywhere between 7040 and
7100 kHz, with 7045 to 7080 kHz as the prime focal area.
The big news for radio amateurs coming from the 2003
World Radiocommunication Conference is that there will be
a dramatic improvement in the 40-meter band soon. The
conference agreed to shift broadcasting stations in Regions 1
and 3 out of the 7100 to 7200-kHz band and to reallocate the
band to the Amateur Radio service. The allocation in Region
2 of 7000 to 7300 kHz remains exclusively Amateur. The
broadcasting band in Regions 1 and 3 will become 7200 to
7450 kHz and in Region 2, 7300 to 7400 kHz. The changes
will take effect on 29 March 2009. How the IARU societies
will handle band planning is not certain at the time of writing.

Fig 2-2—W8LRL started DXing on 160 in 1972. In
January, 2003, Wally worked VU2PAI for #310 on
160 meters.

DX-Operating on the Low Bands

CHAP2.pmd

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2/8/2005, 9:43 AM

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