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MARS and the Yaesu Mark V series Transceivers
Hi everybody. I am the happy owner of a Mark V Field. I have
used Doug’s excellent site on a number of occasions to look up
information on the FT-1000 series of Yaesu radios. Recently I
asked Doug if he would be interested in having a small write-up
about the Mark V is MARS service. He was said he would be happy
to carry the information. So here it is.
First a short word about MARS or the Military Affiliate Radio
System. Mars is actually made up of three service affiliated
components: Army MARS, Navy-Marine Corps MARS and Air Force
MARS. Each service has its own procedures for handling traffic
(SSB and digital) but all share common emergency reporting
procedures and all co-operate with each other.
In one form or another Mars has been around since prior to World
War II. Over these many years, Mars responsibility has changed
as technology and requirements have changed. During World War II
amateur radio in general and MARS in particular provided a quick
availability of trained radio personnel for all the services. In
later years MARS principle role was providing morale and welfare
support for deployed servicemen and women. This support included
MARSGRAMS and phone patches so that service personnel could stay
in touch with their families. Today e-mail, satellites,
telephones and VoIP have replaced HF radio in terms of morale
and welfare. So what is MARS up to today?
Today, Mars has two primary missions. The first is to be a rapid
liaison to the military services in support of national defense
and homeland security. In the event of an incident occurring in
the United States or its territories, immediate reports would be
sent to the military services. This is achieved via radio
assisted e-mail in the case of Army MARS. The second mission is
to handle traffic for civilian emergency services such as the
Red Cross, state and local officials and similar entities.
Normally ARES/RACES would handle shorter range traffic and
provide mobile support with Mars handling longer haul traffic.
To accomplish these purposes, MARS members practice traffic nets
using multimode communications, Near Vertical Incident Skywave (NVIS)
transmissions and advanced netting techniques to include MARS-PCALE
which is Automatic Link Establishment (ALE). These activities
take place primarily on HF although there are some VHF nets.
For those not familiar with NVIS, it is a technique for sending
radio waves straight up into the ionosphere such that a radio
umbrella is created reaching out in all directions from the
sending station to a radius of 300-500 miles. When conditions
are very good, a 25 watt station can have S-9 signals saturate a
very large circle. In my case, I have reached out over a
thousand miles. The technique was first developed in World War
II and now is used extensively by the military.
So what has all this to do with the Mark V Field? With the above
background, I would like to share my experiences with the Mark V
Field in this service. I have several others types of equipment,
but none has served me as well so far as the Field.
My current activities in Oregon Army MARS involve training and
acting as a Net Control Station. The way we are set up is that
each week there are a series of nets scheduled to accomplish a
number of things include training, passing traffic, working with
new multimode digital tools, etc. Each net has a primary
frequency and an alternate frequency in case propagation is
poor. Additional frequencies are also available as necessary. So
let’s look at the role of a Net Control Station using the Mark V
Field.
MARS Frequency Conversion and NTIA compliance
The Mark V and the Field are setup to operate on amateur radio
frequencies. However, both units are easily converted to MARS
and CAP use without violating the warranty by contacting Yaesu
for conversion instructions. Yaesu will ask for a copy of your
MARS or CAP license first. At the moment, one does not need to
be NTIA compliant for MARS. However, if you plan to work with
certain emergency services, e.g. FEMA, or you plan to work with
the Civil Air Patrol, you will need to be NTIA compliant. For
the Field, that means adding the TCX0-6 high stability crystal.
Multiple Frequency Monitoring
Before starting a net, I set the alternate frequency into the
alternate receiver of the Field. The alternate receiver is not
top of the line, but it is very effective in monitoring and
being able to switch between alternative and primary
frequencies. It is also very useful for monitoring other nets or
traffic handling on other frequencies. There is also a situation
that comes up frequently whereby one has to do frequency checks
for propagation. This is normally done by assigning two net
members to checkout the alternate frequency. Here it is very
useful to be able to monitor both conversations. The fact that
filters can be inserted in the alternate receiver is helpful
also. I also note that once the MARS modification is done that
the frequency split could be up to several MHz and maybe more.
This works well since I use a broadband antenna (1.8-30 MHz).
Signal Strength and Noise Control
The Field has a very good front end. While QRM is not a usual
problem due to channelized operations, QRN and sever fading
frequently are. The first defense is the 18 db attenuator with
which I can separate out the signal from the noise. The second
is closing down the bandwidth with the filter system. After that
the noise fighting circuits come in and they are very effective.
NVIS signals can go from noise level to 40 over S-9 very
quickly. I’ve never had an overload problem with the Field,
although I have with other higher end equipment. I find overall,
that with the Field that I am the last one who can still copy
after the propagation has gone to blazes.
Digital Modes
I haven’t tried everything yet but the Field seems fine with
RTTY, PSK31, MT-63, Pactor I, AMTOR, etc. I am about to set it
up with it up with TRX Manager for computer control. By the way,
MT-63 is very popular with MARS and works very well in mixed
mode with SSB. Amateur stations typically don’t use mixed mode,
but we in MARS find it very important to have several ways to
handle traffic. Generally voice is used for short urgent
communications and net control. However, as message traffic
becomes longer or more complex, digital is critical. As an
example, we may have to transmit requests for medicine and
similar supplies. It is much more effective and efficient to
handle this kind of traffic with digital modes. The chances of
mistakes using voice are high and repeats slow the whole process
down considerably.
New Modes
As of this writing, Army MARS has not yet approved WinLink 2000
for MARS use although the older version is OK. On the other
hand, while WinLink 2000 is very good with Pactor III, it
remains very expensive. The new SCAMP mode may solve the expense
problem. But there is a new mode that is much in use in the
military and other governmental services. It is ALE or Automatic
Link Establishment. Without going into detail, ALE facilitates
the process of communications by deciding at any given time
which frequency is best (out of the group of assigned
frequencies) for the assigned net stations to communicate on.
(There are also a lot of other features which probably are saved
for another time.) The military and commercial equipment to
achieve this is quite expensive; however, due to the good work
of our British friends, a PC version is becoming available.
Hence, like so many other things, software is taking over much
of the work of specific hardware. The Mars version of this
software is called MARS-PCALE and is available for free. To
date, many transceivers have had there software completed by the
MARS software group. The Mark V series at the moment only has
the basic software completed, not all the special features so I
can’t report on it yet.
Summary
The Mark V Field is the best that I have used so far for MARS
work. In addition to a great front end, good noise fighting
features, dual receive and other features; the Field can be
easily plugged into a high endurance gel cell battery. I have
put the Field on DC many times for emergency simulation and
other purposes. If Yaesu asked me about some improvements,
perhaps I could think of a few like adding six meters without
spending $1500 dollars for the transverter and power supply. But
that is really not a problem since the Field with the TCXO-6 is
a very stable and sensitive platform for some of the new
transverters coming on the market.
I guess maybe I should mention something else to be fair. I was
first licensed in 1952. I think this means two things. First, I
like all my controls in front of me instead of all on menus. And
second that I am old and a lot of the new equipment is very
difficult for me to operate because of its increasing small
size. I may form an alternate opinion after using TRX-Manager;
however, being net control can be a fast and furious business,
and the equipment needs to be able to keep up with the
situation. Your mileage may vary.
Barry AA7ZC/AARØZC/AAMØTOR
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