|Top of the Hill||Boots and Blisters||Business as Usual:Meeting Minutes|
|Gearing Up||Feature Article||Disclaimer/Copyright|
|Top of the Hill||by Larry Mervine , President|
See you out there.
|Boots and Blisters||by Tony Gaier, Training Officer|
We are over halfway through the first six months of the year and there are nine individuals that have not completed their required training for this six month period. There are only five sanctioned training events left in this six month period so please plan your schedule to get the two required training events before the end of June.
We have two training opportunities between now and the next business meeting. April 24th, at 6:30 pm there will be a Night Land Navigation Training at Bear Canyon Trailhead. ESCAPE will be April 30-May 2nd at Bonita Park in Ruidoso.
Just a reminder, you need to register for ESCAPE by April 15th to receive the discounted registration fee. Also, lodging and meals will be on a "upon availability" basis after the 15th. The registration form is available at the following address: http://www.nmesc.org/nmesc_files/2004_ESCAPE_app-1.pdf
If you have any questions concerning training events please call me at home or on my cellular phone.
|Business as Usual:Meeting Minutes||by Aidan Thompson, Secretary|
The meeting kicked off at 19:22. The president introduced the officers and 6 new attendees.
Tony recapped the previous months events (Land Nav Training, Winter bivvy, and Rescue Sled Training). This month there will be a Litter Haul training at Piedra Lisa trail head, a Search Techniques Training and Escape 2004 on the weekend of April 30-May 2. Early registration for ESCAPE ends on April 15.
Aidan declared a general amnesty on all old mission reports. Like prodigal sons, they will be welcomed back without any unkind words. Several reports from last year have recently been recovered.
Bob reported that four new members are ready to become prospective members.
Alex reported on behalf of Adam. The P.R. meeting has been changed from March 31 to March 25, Taco Cabana, 6:30 p.m. On May 29 the team will do a fireside chat at Elena Gallegos. The following morning we will host a hike.
The meeting ended at 20:30.
|Gearing Up||by Mark Espelien, Equipment Committee chair|
I should soon have one of the team radios checked back in. Members can check out radios (and GPSs, etc.) for a six month period to learn how to use them, then hopefully will buy their own! Contact me if you are interested.
Also, we have put a hold on selling the "group only" pagers until we have finished the switch to the new models. In addition, I will arrange to switch out pagers for those who already own one. Stay tuned.
|Hamming it up, Part 2||by Tom Russo|
In my last installment I tried to encourage team members to get started in amateur radio. In this installment I'd like to go over some of the various communications modes hams can use, talk a tiny bit about the equipment needed to use them, and how they might be useful in SAR. Hams can make an immediate contribution to the team by serving as communicators in field teams --- the simple added ability to use the network of linked ham repeaters we have in New Mexico greatly improves the communications environment over that we'd have if we only used 155.160. But voice operation over two-meter handheld radios is just the tip of the iceberg.
For the most part, SAR communications is dominated by the voice modes, and specifically frequency modulated (FM) signals [Exception: aviation radios are AM, and most of the radios we carry are incapable of communicating with Civil Air Patrol aircraft, requiring separate communications infrastructure for air search management]. Ham radio repeaters located on most major peaks vastly improve the range of our radios, and you will find that there are not all that many areas of New Mexico without good repeater coverage (although there are some notable exceptions near the Gila wilderness).
A repeater is a radio that listens on one frequency and retransmits on another. In most cases, these are located at high points and run quite a bit of output power. I've printed many columns here listing the available repeaters in the area, so I won't do that again. I highly recommend that all Albuquerque hams join the Upper Rio FM Society, which owns many repeaters in the state. Their web site has some good repeater maps.
NM SAR Support has a portable "cross band repeater" that they can deploy on missions. This is somewhat different from the usual repeaters we use in day-to-day operation. The cross band repeater listens on one VHF frequency (i.e. in the 144 MHz range) and retransmits on a UHF frequency (i.e. in the 444MHz range), and vice versa. It is primarly used to extend the reach of base-to-field communications, and does not generally aid team-to-team comm: in order to use it as a repeater, one person needs to be using a UHF radio, the other a VHF. When deployed on a mission, base communicators work on UHF leaving field teams to use their normal VHF radios set to the mission simplex frequency. The cross-band repeater takes care of linking the two. If you have a "dual band" radio you can also use the cross band repeater, transmitting on one band, receiving on the other. In addition to the one that SAR Support maintains for quick deployment, many dual band radios are capable of being put into service as cross band repeaters, including some handheld radios.
Packet radio is primarily a technique for linking computers via radio, but a specialized application of packet radio has found quite a home in SAR work.
In packet radio, digital data is "packetized" by a special device known as a Terminal Node Controller (TNC). It takes data from a computer, adds some information such as your callsign and a destination address (another callsign), then creates sounds that can be piped through a radio and decoded by the receiving station.
Applications of packet radio include packet bulletin boards and a primitive form of email. Hams can use their packet stations to "connect" to other stations, enter messages on the bulletin boards, leave messeges for other stations, and generally pass traffic through their computer keyboards. Packet has its place in emergency communication networks, as the communicator can simply type a message and have it delivered verbatim to the recipient without requiring a human to transcribe it.
Where packet radio has become common in SAR work is the application known as APRS --- Automatic Position Reporting System. APRS is a protocol used on top of packet radio to transmit GPS positions and some other data. Programs running on packet-connected computers can monitor that data and plot the positions of the transmitting stations in real time on maps. The nice thing about APRS is that it is possible to make a very small tracking device that is capable only of encoding GPS data into packets and transmitting them, without needing a computer or TNC with their extra functionality. In SAR work, field teams can carry these simple "trackers" and base can use their full packet station to keep a tactical display of teams in the field.
It is possible to make a packet radio station without actually buying a TNC if you wire up your computer's sound card to a radio. A special driver can be downloaded for free that creates a "virtual" TNC using the sound card, and some APRS programs can use this instead of a hardware TNC.
There are also Palm Pilot programs that can connect to lightweight TNCs and GPS units to provide a portable APRS plotting capability.
Slow Scan TV is another application of amateur radio that turns digital data -- in this case pictures --- into sounds that can be transmitted to another station and decoded. In SSTV the device that converts pictures to sounds is known as a "scan converter." SSTV used to require lots of specialized equipment, but is getting a bit of a resurgence now that computers with sound cards are so available: you can take a regular digital picture, say directly from your digital camera, and a program can convert the image directly to sounds sent to the sound card, which are then in turn piped into the microphone input of a ham radio. On the other end, the speaker output of a radio is fed into a sound card's input, and the process is reversed.
In addition to use with computers, Kenwood makes a hand-held Slow Scan TV device that can plug directly into their radios (and other brands of radios with appropriate home-made adapters) --- it contains both a digital camera and an LCD display so that you can send and receive photographs. This could become a valuable tool in SAR work, allowing teams to transmit still photographs directly to base. It is currently an underutilized tool, but SAR Support does have two of these devices that they can deploy with field teams.
A program that can encode and decode SSTV signals was included on the CDs that went with the Comm training on 21 June 2003 --- I still have plenty of those left if you'd like one.
In the next installment I'd like to talk more about general emergency communications and educational opportunities for those who would like to serve in that capacity.
|Disclaimer and Copyright notice||the Editors|