Near vertical incidence skywave, or NVIS, is a skywave radio-wave propagation path that provides usable signals in the range between groundwave and conventional skywave distances—usually 30–400 miles (50–650 km). It is used for military and paramilitary communications, broadcasting, especially in the tropics, and by radio amateurs. The radio waves travel near-vertically upwards into the ionosphere, where they are refracted back down and can be received within a circular region up to 650 km from the transmitter. If the frequency is too high (that is, above the critical frequency of the ionospheric F layer), refraction fails to occur and if it is too low, absorption in the ionospheric D layer may reduce the signal strength. There is no fundamental difference between NVIS and conventional skywave propagation; the practical distinction arises solely from different desirable radiation patterns of the antennas (near vertical for NVIS, near horizontal for conventional long-range skywave propagation).
Traffic nets handle formatted written messages between served agency locations or between other nets. In emergency operations, these nets may handle the majority of message originations and deliveries. Messages to or from outside the immediate area may be handled by a Section-level net, and depending on the distances involved and the degree to which the public telephone network and Internet are impaired, by Region Nets and Area Nets. Even if you expect to handle traffic primarily on VHF/UHF repeaters, understanding how these layers of nets operate will help you to optimize your use of the system. HF traffic nets can provide you additional practice and expose you to traffic handling that you might not encounter on VHF/UHF. During an emergency ARES and the National Traffic System (NTS) work together closely, so it’s a good idea to understand emergency traffic from the NTS operator’s perspective.
In general, the tactical net(s) handle the primary on-site emergency communications. Their mission may be handling communications for a served agency, weather monitoring and reporting, river gauging, or a variety of other tasks that do not require a formal written message. Often a tactical net may be set up as a “sub net” to handle specific types of traffic during high volume emergency situations. In such cases an additional NCS may be assigned for the sub net.
Health and Welfare (H&W) Nets
These nets usually handle messages between concerned friends, families and persons in the disaster area. Most H&W nets will be on HF bands, but local VHF or UHF “feeder” nets may be needed within a disaster area. Band conditions, operator license constraints and specific use needs will most always determine which mode may be the best choice for determining the mode of certain net operations.
When incoming operators arrive on scene this is the net that they would check into to receive assignments, or to be reassigned as needs change. A resource net may also be used to locate needed equipment, or operators with specific skills. Several different resource nets may be used in large-scale events. One might be used for collecting new volunteers over a wide area, and other local nets could be used for initial assignments. If required due to geography or high net activity, a third net could handle on-going logistical support needs.
Did you know?
The National Institute of Standards and Technology (NIST) operates radio stations WWV from Ft. Collins, Colorado and WWVH from Kauai, Hawaii. WWV and WWVH broadcast time and frequency information on a 24/7 basis. Broadcast information includes time announcements, standard time intervals, standard frequencies, UT1 time corrections, a BCD time code, geophysical alerts, and marine storm warnings.
Each frequency carries the same information. Multiple frequencies are used because the quality of HF reception depends on many factors. WWV and WWVH broadcast on the frequencies listed in the table below, using double sideband, amplitude modulation.
The National Research Institute of Canada operates radio station CHU to disseminate the official time on a 24/7 basis. Each minute, CHU broadcasts time data on the frequencies listed below and includes: time of day (UTC), day of year (1-366), Gregorian year (4 digits), and additional time details. CHU broadcasts time codes using full-carrier upper-sideband modulation that can be read by a computer with a Bell 103 compatible modem.
WWV / WWVH Frequencies (MHz) CHU Frequencies (MHz)
20.0000 (WWV only)
To be of real use in ARES today, you should be familiar with the Incident Command System, and the National Incident Management System… this is how state and local emergency response groups deal with multi-agency involvement, and as we will be dealing in that way, we should be intimately familiar with the systems… Fortunately for us, the training in these systems is free of charge, available from FEMA…
All free, online.
While hams are not paid communications professionals, our behavior and skills should be nothing less. Little else damages our reputation like an unprofessional attitude. Volunteers of all kinds have a bad reputation for “wannabe” behavior and an inappropriate appearance. Police and fire personnel pride themselves on their professional look and demeanor, and they do not want volunteers to detract from that image or impede them in their work. Here are some suggestions:
• Know your place – you are not sworn police officers or firefighters
• You are there to meet THEIR needs, not yours
• They define their needs, not you
• Dress as they want you to – not as you would like to
• Most important, leave your ego at home. You are not in charge
I just wanted to give a shout out in spirit and with lots of Heart to Tom Senerchia, our Kent County DEC, who has been hospitalized and may be out of commission for some time. Please, all of us, keep Tom in your hearts and prayers.
Update 5/3: Our Kent County DEC, Tom Senerchia, KA1VAY, is now home dealing with Physical Therapy… this is good news… keep him in your thoughts.
RI Section Emergency Coordinator
There are several upcoming Skywarn trainings being offered by the National Weather Service, which will teach you to become a NWS Spotter. If you have not taken the course, or retaken it within the last 5 years, as required, here is your opportunity.
Wednesday, April 25 at 7 PM – 9:30 PM EDT
Foster Center Volunteer Fire Company
86 Foster Center Rd, Foster, Rhode Island 02825
Saturday, May 12 at 10 AM – 12:30 PM EDT
Middletown Fire Department
239 Wyatt Rd, Middletown, Rhode Island 02842
Tuesday, May 15 at 7 PM – 9 PM EDT
Rice-Cobb Auditorium at the Sturdy Memorial Hospital
211 Park St, Attleboro, Massachusetts 02703
All are welcome
I am recruiting hams for the American Diabetes Association’s Tour de Cure bicycle ride on Sunday, June 03, 2018. Ham radio support of this event is vital to the safety of riders. We provide communications to and from the rest stops on the routes and along the routes. All routes begin and end at the Pharmacy building on the University of Rhode Island Kingstown Campus. The routes cover a large area, most of Washington county east of route 95. There are changes planned to the routes for this year and I will provide that information once the routes are finalized. They are also considering a 5K run /walk to run concurrently with the bike rides for this year.
The Tour de Cure is a daylong event beginning around 0530. Accommodations may be able to be made if you aren’t available for the whole day. Additional details will follow as they become finalized.
I am looking for 12 to 14 SAG vehicles with a ham and navigator, the navigator does not need to be a ham, for the 5 separate riding routes. Sag vehicles must have good mobile communications equipment. APRS capability is a definite plus.
I am also in need of hams for 7 rest stops for communication duties. There will be other volunteers at the rest stops to handle the rest stop duties. Rest Stops hams should have a good communications set up as well. A mobile radio with a good antenna is the best option but HTs with a good antenna will also work at some locations.
This is a great cause to support, showcase amateur radio capabilities, practice emergency skills and have fun. Diabetes is a disease in which the body does not produce or properly use insulin. Insulin is a hormone that is needed to convert sugar, starches and other food into energy needed for daily life. The cause of diabetes continues to be a mystery. Both genetics and environmental factors such as obesity and lack of exercise appear to play roles in the cause of type 2 diabetes. Nearly 29 million children and adults in this country are diagnosed with diabetes, so the mission of the ADA is an urgent one. Everything they do forms the underpinning for that mission: to prevent and cure diabetes and to improve the lives of all people affected by diabetes. The money from events like the Tour de Cure goes to support research and educational information.
Please let me know as soon as possible if you are available or not and if you would like to be a SAG or at a rest stop, I will do my best to accommodate your request. Please let me know what your communications equipment is, Mobile/HT/APRS etc., and your time availability. If you know anyone else that would like to help please have them contact me. If you aren’t available pass this request on to a ham you think may be interested.
Westerly Amateur Radio Team
Washington County District Emergency Coordinator
In order to increase participation and serve our membership better, the ARES leadership team has decided that the RI ARES VHF Net should be held on the 2nd Tuesday of each month at 1900.
Mark your calendars, the next Net is February 13, 2018 at 1900.
From K1NTP Mike, December 7th, 2017
(reposted from Facebook with permission)
Thanks to financial support from Bishop Hendricken High School and a community grant from IBM (via Newport County Radio Club), Mike K1NPT and Denis KD1HA (in the photo) installed antennas on a drizzly Tuesday atop the Warwick school. Hendricken has at least six licensed students who are keen to get on the air in their newly renovated ham shack.
If you’re wondering what kind of antenna that is, it’s the Ubiquiti 2.4GHz AirMax Omni, 13dBi, using the Rocket node that has been reflashed to allow self-discovering. “mesh” networking data operations on amateur freqs. See AREDN.org for more info. Great application for this network include voice-over-IP telephony, IP cameras, remote software defined radios, web servers, Winlink access. This node will be powered by 24VDC Power-over-Ethernet.
Update January 9th, 2018
I’m please to report that this Bishop Hendricken High SchoolAREDN node is now on-the-air (Student Mac, KC1CZW on the VHF radio).