QRZ! Ham Radio 1/QRZ Ham Radio Callsign Database - December 1993.iso/arrl/faq_6m

Internet Message Format | 1993-11-21 | 12.5 KB

From: [e-mail] (Randall Rhea)
Newsgroups: rec.radio.amateur.misc
Subject: 6 meters: Frequently Asked Questions
Date: 21 Jun 93 17:00:39 GMT
Organization: Informix Software, Inc.
Lines: 244

I have been working on a 6m FAQ.  Comments, corrections, etc.
are welcome.

            THE SIX METER AMATEUR RADIO BAND
              FREQUENTLY ASKED QUESTIONS
   (Designed to help encourage hams to use and enjoy this band!)


WHAT IS THE SIX-METER BAND?  The 6 meter band is a portion
of the RF spectrum allocated to amateur radio.  The band
usually behaves like a VHF band similar to 2 meters.  During one of
the rare F2 openings, propagation is more like an HF band such as
10 meters.  The band is fun and fascinating because just about all
types of propagation pop up on 6m at one time or another.
The band is an acquired taste: a few hams work the band regularly,
but most hams never work it at all.  Once you acquire the
taste, you tend to be hooked for life.  The band has become
more popular in recent years with the help of greater
availability of better rigs.  There two types of 6m operators:
the ones who use FM or packet for local work, and ones who
work DX with SSB.  (Some like me even do both!)

WHAT ARE THE FREQUENCIES?  In the U.S. and some other countries,
the six-meter amateur radio band lies between 50 and 54 MHz, just
below TV channel 2 in the U.S.   In some other countries,
6m is allocated much less bandwidth.  New Zealand's band starts
at 51.0.  Check your allocations for your particular country.
They change pretty often as the band is becoming more popular.

WAS 6M ONCE TV CHANNEL ONE?   Televisions in the U.S. start at
channel 2.  Some ham books say that 6m was once channel 1.
This is not true.  Just after WWII, Channel 1 in the U.S.
was allocated 44 to 50 MHz, with 6m occupying the same
spot as it does today.  By 1948, interference from police
radios and hams made channel 1 nearly unusable. Early TV sets had
little or no RF sheilding.  The ARRL recommended that channel
2 (54-60 MHz) be eliminated, but the FCC decided to axe channel
1 instead.

IS FM USED ON 6M?  Yes, but not that often in most areas.
Most 6m enthusiasts use only SSB and sometimes CW.
The main FM simplex frequency is 52.525 MHz.
Your local range is better on 6m with the same power and a similar
antenna.  If 2m is too crowded in your area, the FM portion
of 6m may be just the solution you need.

ARE REPEATERS USED?  There are a few 6m repeaters listed in the
ARRL Repeater Directory, but some of them are not operational.
This will depend on your area.  The offset in the U.S. is usually
one MHz. (e.g. 53.330 out, 52.330 in)

HOW DO I KNOW IF THERE IS AN OPENING?  Of course, the best
way is to check for an opening is to listen to 6m, especially
for the beacons that are listed in the ARRL Repeater Directory.
Monitor 50.110 and 50.125 for SSB openings.  You can
also monitor 28.885 MHz, the "10 Meter VHF Liaison Frequency",
where hams report VHF openings and schedule contacts.  You'll
hear some of those "pros" you see in QST like W5UN on that
frequency.

WHAT ARE THE MOST POPULAR FREQUENCIES?  Per the FCC, 50.0 to
50.1 is reserved for CW work in the U.S.   Most operation is
SSB.  50.100 is the most popular SSB DX frequency, and 50.100
to 50.124 should be used only for DX.  Some hams tend to
discourage (or flame) U.S. domestic stations from calling
CQ in this "DX window".  The other popular frequencies tend
to vary from area to area, so the following is only a general
guide for beginners:  50.125 is the U.S. domestic calling
frequency, and most domestic SSB is found between 50.125 and
50.200.  Only during hot F2 openings do you find SSB above 50.200.

DO I NEED A BEAM ANTENNA?   If you want to work DX, yes.
You can have fun with a vertical during openings, (I do with
an Icom 726 in my car) but the pros use beams. Everyone is
horizontally polarized, but cross-polarization doesn't matter
for Es, F2, or Aurora.  A few stations use 3-element beams, but
a 4 or 5 element beam is so small that a LOT of people use them.
Quite a few people have Cushcraft 6-element "Boomers". There are a
few other big beams, and the lunatic fringe stacks them. For example,
K6QXY has a stack of 4 six-meter beams, each with a 50ft (15m)
boom. The higher the tower the better!  I live in subdivision
where no outdoor antennas are allowed, so I use a 2-element beam in
the attic, and it works OK.  I also use a vertical for local FM
work.  RG8 or RG213 is plenty good enough cable for most people.
Antenna-mounted preamps are never needed.

IS 6M NOISY?  External noise is fairly high at 50 MHz.  It
overrides the front-end noise figure on about all the rigs on the
market today unless you have a LOT of cable loss or a VERY quiet
location.

IS THERE PACKET WORK ON 6M?   It depends on the area.  Local
packet work can be found in the higher frequency portions
of the band.  There has been very little DX packet work.

CAN I RUN RADIO-CONTROLLED EQUIPMENT USING 6M?  This
is legal in the U.S. for licensed hams.   Check the ARRL
Repeater Directory for suggested frequencies.

WHAT ARE "GRID SQUARES"?  On VHF and up bands, the world
has been divided in 1-degree lat x 2-degree long "squares"
which start at the south pole and date line and "read right
up".  SSB stations will always identify their grid square
along with their call sign, e.g. "KK6MY DM87".  Each square
is also divided into sub-squares.  European stations
like the subsquares; most US stations don't even know their own.
In any case, the "squares" and their VUCC awards have been
a wonderful interest builder, and have kept the QSL printers in
business!   Check the ARRL Operating Manual for a map
of the grid squares.

WHAT RIGS ARE USED?  Probably 50% of the active stations have 80
to 150 W output, either from old Icom 551D s (the 551 is 10W), or
from solid-state (brick) amplifiers following the many types of 10W
rigs, such as the Yaesu Ft-620B or the Kenwood TS-600.  The Icom
575H is very popular, as it has an excellent receiver and
100 watts (the 575A is 10 watts).  HF rigs that add 6m (such
as the Icom 726) are usable but not as good as radios designed
for 6m, especially in the receivers.  Perhaps 40% of the stations run
just 10 to 20 W, but most of them either get an amplifier or drop
out after a year or so.  The remaining 10% have tube rigs
such as the Drake TR-6.  Good 6m rigs tend to be expensive, even
on the used market.  Swan and Heathkit tube rigs are the least
expensive and can be quite usable, but you will run into problems
typical of older rigs, such as drift (especially on the Swan).
The kilowatt is quite rare on 6m.  The norm for serious stations is
100 to 150 watts.

CAN I USE A TRANSVERTER WITH AN HF RIG TO GET ON 6M?  Yes, but
you will either spend a lot of time tinkering with a
soldering iron, or you will spend a lot of money on the
high-end transverters from SSB Electronics.  An SSB Electronics
6m transverter fully equipped will run you $800, but may
outperform most of the VHF all-mode rigs.  (or so SSB Electronics
claims) Some hams build transverters, but you need a good level
of electronics expertise.

I LISTEN TO 6M OCCASIONALLY, BUT I NEVER HEAR ANYONE.  Openings
on 6m are rare, especially during low points in the sunspot
cycle.  For hams in far northern latitudes (say 50 degrees and above),
aurora openings are common. The most common openings in middle and
southern latitudes are a result of sporatic E (Es), which occurs most
often in June.  F2 openings occur only when the solar flux is high.
An explanation of the many types of propagation on 6m follows.

HOW OFTEN ARE THERE F2 OPENINGS?  F2 propagation, the
kind that we know and love on 20 meters, occurs rarely
on 6m.  Only at the peak times of the sunspot cycle, a few
years out of each eleven, does the band open up for F2.  When
it does happen, the band becomes a frenzy of activity, and
behaves similar to 10 meters.  In the last cycle, there
were many openings in 1989 through 1991, but that cycle had
an unsually long period of peak activity.   Openings occur
most often in Autumn during the daytime.  A few stations
have worked 100 or more countries, but they have been patiently
working the fleeting openings for many years.  The March, 1993
QST magazine has an excellent article on 6m propagation
that shows a correlation between solar flux and openings.

HOW IS TROPO PROPAGATION ON 6M?   The ordinary ground-wave tropo
range on six isn't quite as great as on two.  There are a
number of reasons.  Since there are so many other propagation
modes on six, people don't try so hard on tropo.  Antenna gain
often is higher on two.  Noise is lower on two.  At least in
the summer, stations like W3BWU (Pittsburgh), W3IDZ (northern NJ)
are easily worked from Maryland with the beam pointing at them,
and can be heard at almost any pointing.  They are in the
150-W class.

HOW IS METEOR PROPAGATION?  Any area workable by meteors
can be worked more easily by Es or aurora.  Even though meteor bursts
are much strong and longer on six than on two, little use has been
made of them.  There has been a VERY little meteor-burst
packet work on six.  W3OTC had the first such contact (with
W0RPK). W3XO worked him a few years later.

WHAT ABOUT IONOSCATTER? Some people think it's really meteors, but
every weekend morning there are a number of nearly-
kilowatt stations working each other on SSB at distances
of about 600 - 1000 miles by ionosperic scatter.  Sigs
are weak, and it takes good beams, height, and power, but
it is very reliable.  See the old NBS papers by Bailey,
Bateman and Kirby, et al.  Bateman and Kirby were/are
hams.  Ross Bateman recently died.  Dick Kirby continues
as head of ITU in Geneva.

HOW IS AURORA?  It is much easier than on two.  SSB is
usually intelligible.  Point north about dusk, most
commonly in March and October/November.  Lots of people
in the far northern latitudes work this mode when it happens.

WHAT ABOUT SPORATIC E (Es)?  Es is the most common propagation
mode on 6m.  The term "sporatic" is accurate: stations can pop
in and out and then fade quickly. I would monitor
50.110, 50.125, and 28.885 MHz to check for Es.  Es has
little or nothing to do with the sunspot cycle; it is
much more a function of the time of year.  Es is most common
in June, but can appear from May to August, and around
Christmas, here in northern latitudes.   In addition to the
common single-hop range of 500 - 1500 miles, there are quite
a few double- and-more hop contacts on 6m.  Now that a number of
Europeans are on six, we find that they can be worked
from the US east coast each summer.  Likewise the
Caribbean stations work all over the US.  The US west
coast can work Hawaii, Alaska, and Mexico.   You will
also hear some hams on June DXPedition trips to Mexico
and the Carribbean; they are easy to work in the late
afternoon or early evening, even with 10W and a vertical.
The VHF contest in the middle of June is also a good time
to work Es.

WHAT ABOUT TRANSEQUATORIAL PROPAGATION? - The southern US gets a
number of openings to South America by some kind of
ionosphericaly-ducted propagation.  The stations are
generally about equidistant either side of the magnetic
equator.  Given exceptional luck, an Es opening linked
into this mode can make it available to more northern
stations.  This mode has bad flutter fading and a touch
of the auroral spectrum spreading.  This mode also works
sometimes on two meters if you use CW and really good
gear.  It has been worked on 432 MHz.

ANY MOONBOUNCE (EME)?  - There have been a few EME contacts on
six, but the required antenna size and high background noise
makes it out of the reach of most people.

WHAT ABOUT TVI PROBLEMS? There is no doubt about it, six
has TVI troubles.  You don't find a lot of people on 6m
in channel 2 areas unless cable is widely subscribed-to.
VCRs are very prone to 6m pickup.  Cordless phones,
baby monitors, and kiddle walkie-talkies operate on 49 MHz.
Most consumer electronic equipment has poor RFI shielding.  The
common connecting or power cable is a quarter-wave antenna for
six. The TV owners have their revenge since the 13th harmonic of
the color subcarrier, or something, of TV sets and TV games puts out
a birdy at 50.113 MHz to bother the 6m operators in return.  There
is also quite a bit of trouble from noisy power distribution lines if
they aren't buried (usually bad insulators or poor guy bonding).

--

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Randall Rhea                                        Informix Software, Inc.
Project Manager, MIS Sales/Marketing Systems    uunet!pyramid!infmx!randall