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SAFE Ark Two Newsletter
Special Radio Edition
Part Three of Three
September 21st, 2013
This special edition of the Newsletter is the third of a special three part series being devoted to the subject of the radio.
The radio is very important to the SAFE Reconstruction concept.
In this third and final part, of the three part series, we will examine the current equipment plan.
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Design of the SAFE EMS Hardware
Whenever I talk to experts about the design of our system the response is:
"That is very simple - surely it has been done before!"
Well, "No."
And why not?
Well, in the first place, any full blown Ham rig will do with ease what
we want to do - so Advanced Hams don't need our little device.
However, Advanced Hams usually spend a couple of thousand dollars, and
often ten times that, on their rigs and hobby. We want a system that
will cost less than $200.
New hams, that are looking for inexpensive systems don't generally want
one that does what ours does because it uses a mode that is only legal
for advanced hams to use. (We however, take an approach that is
COMPLETELY Legal).
There are a few designs that have been built by hobbyists that are
pretty close to our need, but they are QRP, which means 'low power'
usually 3-10 watts. We want 20w+. We thought that we could add a power
amplifier to that type of unit/design but it turns out they are just too
unstable to work at the higher power.
A ham will reply, but what difference does it make? I have been able to talk around the world on my QRP.
Yes, but unreliably. We want to talk relatively nearby - and reliably.
Well, "then perhaps you need to consider a different system."
We have been told that many dozens of times.
And this is where we have gotten dozens of recommendations - but none of
them will do the job. The most common suggestion is that everyone learn
CW (Morse Code). Yeah.
Repeaters, another suggestion - won't be available.
CB - doesn't go far enough although some people talk about power modifications.
Some have said, "Just go to an existing design, and ask them to tweak what you need."
Yep, if we will give them a money up front order for tens of thousands of units.
And the list goes on.
It all comes down to money. Apparently the sole motivator today.
So, two years later we have gone down many, many paths and are still at
square one - in trying to get our design, although we do understand
better now what won't work in trying to obtain the design that we want.
There are many reasons why the methods and practices common to hams are
not satisfactory to our needs. The equipment is too expensive, the
antennas are often difficult to put up, the bands and frequencies that
they often use don't meet our special purposes, the systems are often
very complicated to use and modes such as CW are very difficult to
learn.
All of the Ham Emergency Radio Nets are designed for where there are
surviving areas around a disaster area. None of them are designed for a
universal catastrophe where there are no untouched areas. Consequently,
most Hams, like most people, think such an idea of universal catastrophe
is nuts.
Each ham may argue vehemently for their favorite system, but we would
not be able as easily, using parameters other than the ones we have
chosen, to convert such a system to our universal calamity model and get
a great number of participants to utilize our SAFE Net.
The New Approach
After all this time there has been suggested to us a new approach that
will allow us to obtain equipment that will achieve our parameters. The
new recommended approach is to use a Transverter with a CB. I had not
heard of the idea when it was first suggested and had to look up what a
Transverter is.
Such a device changes one frequency to another. It is NOT possible for
every frequency on a CB radio but it just so happens that a transverter
can be designed to change CB Channel 40 to the 80m band that we wish to
use.
Anyone can legally buy a CB transceiver. No license is required. The
transverter is neither fish nor fowl. Neither transmitter or
transceiver, so anyone can also buy the transverter. The issue is
marrying them together along with the amplifier.
That string of CB radio, Transverter, Amplifier, with a NVIS antenna, is
then connected together to a computer sound card and the computer. We
will then have 80m band PSK31 at the required wattage. Legal to purchase
and own, and legal to receive PSK31 by anyone, at anytime, whether a
licensed ham or not, but illegal to transmit on except by an Advanced
Ham, so we will disable the 80m transmitting capability in a way that a
ham will have to activate it.
It will also be illegal to use ham equipment during a universal
catastrophe if the Presidential Executive Order is activated, but that
is a bridge that will have to be crossed at that time.
There are a couple of other neat things about this new design. The
designer, David Cuthbert, wishes to make the CB part generic. This means
that you should be able to buy any SSB CB with Channel 40 and make it
work with our transverter.
The CB radio will still fully work as a CB on all 40 Channels. You can
spend from hundreds of dollars to a few dollars for a CB, however, we
hope to try out some of the less expensive ones and if we find one that
works well, so that we can standardize to that one, we may be able to
get a very good price with a bulk buy. So far we look to be on course to
come in under our target price of $200 for the whole system. The lower
we can get the price - the more people that should participate - many
with multiple units so that they can equip family members or friends
that are less than three or four hundred miles away.
Our system will still require an external NVIS antenna, an external 12v
power supply, the sound card, computer and and computer software, and a
PTT button. We are considering a couple of optional external packages
such as an antenna tuner.
The following is a concept diagram of the system.
The necessity will remain for our participants to know how to assemble
the system, activate the transmit (only in time of dire emergency), (if
they are not Advanced Hams), the procedures for operating in our network
and the overall functions and purposes of SAFE as explained in the
Paper. This is the reason as explained, in Part Two of these Special
Radio Newsletters, about the SAFE EMS Ham Net meetings that we hope to
hold in your state in a location near enough for you to attend.
Specifics about using the SAFE Ham Net, the User Interface, and setting up the equipment and special antenna are found in
The SAFE EMS Manual
More details about how the radio fits into the SAFE Plan is to be found in:
"The Paper" which is also available as a pdf press master. And of course with the explanation about LERNs in the book "Society AFTER Doomsday".
The CB/Transverter Designer
David Cuthbert will be the lead Engineer on this new design,
so allow me to introduce Dave to you.
Dave retired this month and says he now has time to devote to the project.
His areas of expertise lie in analog electronics. He has done power
supply design from milliwatts to a megawatt, high voltage (to 70 kV)
video, RF, semiconductor test, metrology, antenna design, signal
integrity, and most recently (EMC) electromagnetic compatibility.
He did commercial EMC at Micron for seven years (mostly at the semiconductor level)
and for the past five years Military EMC at L3. Along the way he has done a constant stream of analog design
and in-house test equipment.
He holds 27 patents and has authored 50 articles, 30 of them on antennas.
He has been an exceptional contributor to eHam, where I found him, with over 5,000 posts there.
Our Alternative Approach
We have a proposal for an alternative approach to developing the radio.
Everyone, including Dave, agrees that this would be the better radio if
it could be achieved. However, it would be considerably more expensive,
require more effort to develop and the development process might be
substantially longer, and could involve some legal
difficulties/obstacles in its manufacture that would have to be
overcome.
Nevertheless, we may undertake a two prong effort. Dr. M. the designer
in the UK is still evaluating the feasibility of this approach.
Further details about the ongoing radio development effort will be reported in regular issues of the SAFE/Ark Two newsletter.
Peace and love,
Bruce
DawnSayer@webpal.org
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