In a communications black out, two-way radio communications are the main alternative to modern conventional communications such as land line phones,
cell phones and internet connections. However, no communications system is without short falls and vulnerabilities. Assuming that some attack or
disaster knocks out conventional communications channels, alternative communications via two-way radios have a number of vulnerabilities and short
Below is a list of vulnerabilities attributed to two-way communications.
1. Electro-magnetic Pulses
2. Lightning Strikes
3. Power Outages
5. Destructive Storms
6. Jamming Interference
Although unpredictable, solar EMPs can be anticipated if the solar storm cycle is high and the damaging solar flares (known as coronal mass ejections
or CMEs) are detected before hitting the earth. If the CME is detected then the EMP intensity and effected areas on earth can be determined just
before the damage can occur. If the coronal mass ejection emitting an EMP is detected as it happens and it is facing the earth, then it will only take
an average of eight and a half minutes to hit the planet. The time can be longer depending on the angle of the flare, current distance from the sun
and what side of the earth is facing the sun.
Obviously there will be little time to react considering the public will most likely be informed last during such an event. In a best case scenario
you will hear about the incoming solar flare at night while you’re on the shaded side of the earth. In any case it would be best to take precautions
long before any type of solar EMP threat is identified.
Nuclear EMP Attack
Although the effects of a nuclear EMP attack are nearly the same as a high intensity solar flare, once the trajectory is determined, there is more
certainty about the intensity, duration and area covered. Concerning the amount of time to prepare for such an attack, a missile launched from Russia
would take about 30 minutes to reach the U.S. However, there is time needed to determine if there was an attack launched and more time needed to
inform military defenses. Then there is the possibility that the launch could occur from a country or a submarine closer than Russia or that the
missile could come from somewhere based in orbit.
Once again, given all the factors there will be little time to react considering the public will likely be last to know and it would be best to take
precautions before hand.
In an EMP event, most antenna towers, including cell phone, wireless internet, commercial broadcast radio and amateur repeater towers would likely
suffer the most damage. Unless hardened against EMPs, even satellite internet and phone systems could suffer damage to the land-sat stations.
Fortunately, these systems are well protected from lightning strikes that will help protect them during an EMP as well.
What precautions can be taken to protect two-way equipment from EMPs?
Storing your two-way radios and equipment in a Faraday cage will protect them from EMPs. Other than burying them underground, this is the best way to
protect your equipment. However, if you use your two-ways on a daily basis, esp. if you have your radio connected to an outdoor antenna, without
protective gear and protective grounding methods you will get your equipment fried in an EMP event.
The best thing to do to protect equipment that is in use is to have your antenna mast properly grounded, your radio in a shielded room, your equipment
disconnected from the antenna coax and unplugged from the electrical outlets when not in use. EMPs will be attracted to your antenna and any wires or
cables that are not buried or otherwise protected making your antenna, coax cable and electrical wires the most vulnerable things in your
A lightning strike to an outdoor antenna will fry your system in an instant and potentially cause a fire or electrocute you . This can be mostly
avoided with using lightning arresters and having a well grounded antenna mast. Without the proper arresters, disconnecting your antenna coax from
your equipment during a lightning storm will at least spare your radio during a lightning strike. Without arresters and enough precautions, a good
lightning strike would cause severe damage to your coax cable and outdoor antenna making them useless.
Both lightning strikes and EMPs cause a similar effect and can be prevented with the same methods and safety equipment. There are instruction guides
available online about how to set up your equipment to save it from damage in both scenarios.
Long term widespread power outages are a problem, but not as nearly severe as an EMP. Most communications systems will have battery or generator
backup systems that kick in during a power outage. These will only last so long unless they are using solar or wind generated backup power. Once there
is no fuel available for generators, systems that rely on those will go down after awhile.
A massive earthquake would take out most of the communications systems in the region of the quake. A shattered infrastructure would be a problem for
any surviving systems. The best protection from an earthquake disaster would be storing equipment in an earthquake proof building or bringing in
equipment from unaffected areas. Mobile two-way systems would be best for surviving an earthquake scenario.
Damaging storms could knock out antenna towers and land-sat antennas as well as cause power outages. Some area road ways could become impassible after
such storms. Hurricanes and tornados would be the worse type of storms to affect communications. As with an earthquake, a shattered infrastructure
would be a problem for any surviving systems.
Solar and nuclear EMPs will cause interference that jams wireless frequencies by exciting the ionosphere. This will certainly jam distant two-way
communications that rely on skipping signals off the ionosphere.
Solar EMP interference will last as long as the solar storms do. During a nuclear EMP, communications can be disrupted for a period of time varying
from seconds to hours. Local two-way “line of sight” communications at higher frequencies will experience little or no disruption during EMPs.
The use of radio frequency jamming equipment is something that can take out all two-way communications. A high power, broad band, radio frequency
pulse generator will jam radar, data links, voice communications or other radio signals. Even someone using normal two-way radios can jam
communications by simply transmitting over the other signals with a stronger signal.
Such signal jamming must be located and disabled to restore normal two-way communications. Locating a land based line of sight jamming signal can be
done by triangulating on the signal with two receivers using directional antennas. A land based jamming signal shooting a signal straight up to the
ionosphere and back down again (near vertical incident sky wave propagation) would be harder to locate. A jamming signal from an orbiting satellite
once located would of course be impossible to disable without specialized weapons like missiles and space based or high powered energy weapons.
edit on 12-3-2016 by MichiganSwampBuck because: corrections made
edit on 12-3-2016 by MichiganSwampBuck because: typo