Bedford County Communications Guide

This guidebook was designed by the Bedford County Amateur Radio Society to inform. While most of the information is geared towards Amateur Radio Operators (hams) in and around Bedford County, we hope it can provide a powerful resource for anyone interested in radio communications technology. A good portion of this text is made to be introductory, so it should prove useful for you even if you are not from Bedford County.

If you are not interested in wireless communications, this book will be less useful, but could still contain some valuable information. It provides contact information for a number of emergency response organizations. We all know to call 911 for immediate emergencies. But do you know how to get in touch with the Red Cross, or PEMA, or FEMA? How would you check on relatives during a flood with no working phone?

About Bedford County


Founded in 1771, Bedford County has a rich history predating the birth of the Union. Bedford County is a small community in central Pennsylvania with approximately 50,000 residents and 25 townships spread over 1,017 miles of mountainous terrain. Each community is typically divided along geographical boundaries such as a mountain ridge or body of water.

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BCARS

History

The Bedford County Amateur Radio Society was formed in 1959 in order to support Bedford County. BCARS was formed by Bedford County reseidents such as Tom Scott K3ETC, and Arden Moser (K3MIU). Several of these “founding fathers” are still in the area today. One of their first tasks was to take charge of the Bedford County Civil Defense, communications system, which as that time was housed in the county court house basement.

Throughout the years, BCARS has maintained a close relationship with Bedford County Emergency Operations, providing communications as needed in disaster situations, as well as assisting with communications at county events. As such, the club has maintained its presence with first the Court House, then the county 911 center, and ultimately moving with the 911 back into the renovated and expanded county court house in 2006(?).

Contact

 BEDFORD COUNTY AMAT RADIO SOCIETY, K3NQT  
 326 E PENN ST  
 BEDFORD, PA 15522-6459  
 USA

Membership

Membership is $20 annually, payable to the treasure (currently Steve Elliot, KA3UDR).

Annual Events

  • June
    • ARRL Field Day
  • October
    • WPA Ares Set Exercise
 

Jurisdictions

Organization ARRL PEMA Red Cross Pennsylvania EMS
Jurisdiction WPA Section, South Zone Two District Central Area and South Central Mountains Regional Task Force. Southern Alleghenies Chapter Southern Alleghenies EMS
Counties Bedford, Blair, Cambria, Franklin, Fulton, Huntingdon, Mifflin, Somerset Bedford, Blair, Centre, Fulton, Huntingdon, Juniata, Mifflin, Snyder Bedford, Blair, Fulton, Huntingdon Bedford, Blair, Cambria, Fulton, Huntingdon, Somerset

-Jurisdiction information provided by KA3EJV


 

Local Civil and Community Organizations

Local Civil and Community Organizations

Add these to your phone or keep them with you. For emergencies, call 911. The numbers below are administrative or non-emergency numbers.

Everett Borough Police 814-652-2312

Everett Fire Department 814-652-2687 http://everettfire32.com/

Everett: Raystown Ambulance Association 814-652-6018 http://raystownambulance.com/

Everett Borough Office 814-652-9202 http://bedford.pacounties.org/everettboro/

National Poison Control 1-800-222-1222

Bedford UPMC Hospital 814-652-2111

Your Safe Haven 814-623-7664

Bedford County Municipalities List http://bedford.pacounties.org/Pages/BedfordCountyMunicipalities.aspx

Civil Air Patrol - The Civil Air Patrol is the volunteer, non-profit auxiliary of the U.S. Air Force. This unit is often relied upon for search and rescue operation, resupply, and homeland defense. (814)623-7476. http://www.bedfordcap.org/

MARS

Red Cross

Boy and Girl Scouts of America

PA National Guard of Everett

FEMA Region III: DC, DE, MD, PA, VA, WV - 1-215-931-5500
FEMA Disaster Assistance: 1-800-621-FEMA (3362)

 

Local Amateur Radio Clubs

  • Blue Knob
  • Somerset
  • Steel City
  • Fulton County?
  • Target Repeater
  • Allegheny Repeater Association
  • Horeshoe Curve/Altoon
 
 

HAM Frequencies

National

  • 144.39 S = APRS Nationwide Freq
  • 145.50-145.80 S = misc and experimental nodes
  • 146.52 S = National VHF simplex calling freq
  • 446.00 S = National UHF simplex calling freq
  • See the ARRL Band-Plan page for more national standardized frequencies

BCARS (K3NQT) Repeaters

Freq PL Tone Notes
145.490- PL 123.00
224.480+ PL 123.00
444.200- PL 123.00

146.580 is the ARES assigned simplex frequency for Bedford County.

Bedford Packet

  • 144.05 Packet stations around Bedford, PA
  • 144.03 Packet stations around Somerset, PA

Nearby Repeaters

Freq PL Location Call Notes
146.610- 123 Altoona W3QZF
146.820- 123 Altoona W3QW
444.600+ 123 Altoona W3VO
442.100+ 167.9 Altoona NU3T http://www.blueknob.info/ Echolink Node: KR3ORY-R
145.490- 123 Bedford K3NQT http://www.bcars.org/
224.480+ N/A Bedford K3NQT
444.200- 123 Bedford K3NQT
147.150+ 167.9 Blue Knob KB3KWD http://www.blueknob.info/ - Linked to WAN Repeater
146.775- 123 Carrolltown KA3ZYC
443.525+ 123 Carrolltown KB3BLF
147.120+ N/A Chambersburg W3ACH
146.865+ 123 Clearfield N3QC
147.390+ 173.8 Rockton N5NWC
443.875+ 123 Dunning Mt NU3T http://www.blueknob.info/
145.310- N/A Huntingdon W3WIV
146.700- N/A Huntingdon WB3CJB
145.390- 123 Johnstown N3YFO
146.940- 123 Johnstown WA3WGN http://www.cambriaradio.com/
147.375+ 123 Johnstown N3LZX at airport (linked to K3SMT 147.195+)
224.680- N/A Johnstown KB3BLF http://www.cambriaraces.org/
442.825+ 123 Johnstown KB3BLF
147.015+ N/A MT. Pleasant KA3JSD
145.290- 123 New Baltimore W3KKC
145.210- 123 New Germany KB3BLF
146.655- 123 North Cambria KE3DR
147.195+ 123 Somerset K3SMT http://www.k3smt.org/
146.625- 123 Somerset WR3AJL http://www.k3smt.org/
145.270- 123 Meyersdale KQ3M
146.835- 123 Seven Springs W3WGX
145.250- 123 McConnellsburg KB3UAG
145.450- 123 State College K3CR
146.760- N/A State College K3HKK
146.850- 146.2 State College W3YA
443.650+ 123 State College K3CR
442.600+ 123 Tussey Mountain/Williamsburg WO3T http://www.blueknob.info/ - Loop Mtn
146.750- 123 Berkely Springs, WV KK3L Linked to WAN Repeater
147.060+ 123 Frederick, MD K3MAD
Linked to WAN

More Information


 

Common Frequencies

All frequencies are in Mhz unless otherwise stated.

Citizens Band (CB)

Citizens Band Radio, commonly referred to as CB is an unlicensed short-range radio service suitable for both personal and commercial uses. In the US, CB communications is set at 27Mhz (the “11-meter band”). Originally a 23-channel service, it has since been expanded to 40 channels. Conventionally, channels 1-35 use “Amplitude Modulation” at a maximum of 4 Watts while Channels 36-40 use “Single Side Band (SSB)”. SSB mode is allowed to use up to 12 Watts of power, giving it an advantage over the AM channels. Technically however, most modern CB radios can do SSB on any channels. This is discouraged as it would cause interference with those using AM on the same channel.

The FCC has set aside channel 9 for emergency use. In most regions, emergency service will listen on channel 9 for emergency calls. Many modern CB radios will also listen on channel 9, even if the operator is actively tuned to another channel. If a broadcast comes in on channel 9, the CB can play it, alerting as many people as possible to the emergency. While not a regulation, most operators consider channel 19 the “common call” frequency for AM modes and channel 36 the common call for frequency for SSB modes.

Ch# Freq Ch# Freq Ch# Freq Ch# Freq
1 26.965 Mhz 11 27.085 Mhz 21 27.215 Mhz 31 27.315 Mhz
2 26.975 Mhz 12 27.105 Mhz 22 27.225 Mhz 32 27.325 Mhz
3 26.985 Mhz 13 27.115 Mhz 23 27.255 Mhz 33 27.335 Mhz
4 27.005 Mhz 14 27.125 Mhz 24 27.235 Mhz 34 27.345 Mhz
5 27.015 Mhz 15 27.135 Mhz 25 27.245 Mhz 35 27.355 Mhz
6 27.025 Mhz 16 27.155 Mhz 26 27.265 Mhz 36 27.365 Mhz
7 27.035 Mhz 17 27.165 Mhz 27 27.275 Mhz 37 27.375 Mhz
8 27.055 Mhz 18 27.175 Mhz 28 27.285 Mhz 38 27.385 Mhz
9 27.065 Mhz 19 27.185 Mhz 29 27.295 Mhz 39 27.395 Mhz
10 27.075 Mhz 20 27.205 Mhz 30 27.305 Mhz 40 27.405 Mhz

MURS

MURS - is an unlicensed “multi-use radio service” limited to 2 watts. No license is required, but some companies (such as Wal-Mart) use MURS radios and tend to get upset when non-employees start coming in on their handhelds.

MURS freq
1 151.82
2 151.88
3 151.94
4 154.57
5 154.6

FRS/GMRS

FRS - “Family Radio Service” limited to 0.5Watts (unlicensed)

GMRS - General Mobile Radio Service is a licensed commercial band permitting up to 50 watts. Hybrid FRS/GMRS radios exist. Channels 1-7 are shared between FRS and GMRS, however FRS radios are limited to the 1/2 watt restriction. Licensed GMRS and unlicensed FRS operators can communication on channels 1-7. Channels 8-14 are FRS only and 15-22 are GMRS only. The channel numbers listed below is the most common for a hybrid radio, though a GMRS only radio will have different frequencies per channel.

Channel freq Channel freq
f/g 1 462.5625 g 12 467.6625
f/g 2 462.5875 g 13 467.6875
f/g3 462.6125 g 14 467.7125
f/g 4 462.6375 g 15 462.55
f/g 5 462.6625 g 16 462.575
f/g 6 462.6875 g 17 462.6
f/g 7 462.7125 g 18 462.625
f 8 467.5625 g 19 462.65
f 9 467.5875 g 20 462.675
f 10 467.6125 g 21 462.7
g 11 467.6375 g 22 462.725

Marine VHF

Marine VHF - is a licensed band used for maritime activity, up to 25 watts is allowed for licensed operators.

Channel freq alt Channel freq alt
01A 156.05 28 157.4 162
05A 156.25 63A 156.175 156.175
6 156.3 65A 156.275 156.275
07A 156.35 66A 156.325 156.325
8 156.4 67 156.375 156.375
9 156.45 68 156.425 156.425
10 156.5 69 156.475 156.475
11 156.55 70 156.525 156.525
12 156.6 156.6 71 156.575 156.575
13 156.65 156.65 72 156.625 156.625
14 156.7 156.7 73 156.675 156.675
15 156.75 74 156.725 156.725
16 156.8 156.8 77 156.875 156.875
17 156.85 156.85 78A 156.925 156.925
18A 156.9 156.9 79A 156.975 156.975
19A 156.95 156.95 80A 157.025 157.025
20 157 161.6 81A 157.075 157.075
20A 157 157 82A 157.125 157.125
21A 157.05 157.05 83A 157.175 157.175
22A 157.1 157.1 84 157.225 161.825
23A 157.15 157.15 85 157.275 161.875
24 157.2 161.8 86 157.325 161.925
25 157.25 161.85 87 157.375 157.375
26 157.3 161.9 88A 157.425 157.425
27 157.35 161.95 AIS 1 161.975 161.975

Search And Rescue Frequencies

Land SAR
Typical freqs. are: 155.160, .175, .205, .220, .235, .265, .280, or .295
If CTCSS is required try 127.3 Hz (3A).

Air SAR
3023, 5680, 8364 kHz (lifeboat/survival craft),
4125 kHz (distress/safety with ships and coast stations)
121.5 MHz emergency and distress
122.9 MHz SAR secondary & training
123.1 MHz SAR primary

Water SAR
156.300 (VHF Marine ch. 06) Safety and SAR
156.450 (VHF Marine ch. 09) Non-commercial supplementary calling
156.800 (VHF Marine ch. 16) DISTRESS and calling
156.850 (VHF Marine ch. 17) State control
157.100 (VHF Marine ch. 22A) Coast Guard Liaison

VHF Marine Channels
6, 9, 15, 16, 21A, 22A (USCG Liaison), 23A, 81A, 83A

USCG Auxiliary
138.475, 142.825, 143.475, 149.200, 150.700

USCG/DOD Joint SAR
345.0 MHz AM initial contact, 282.8 MHz AM working

Military SAR
40.50 wideband FM US Army/USN SAR
138.450 AM 138.750 AM USAF SAR


 
 

Public Service Frequencies

County Police

GroupFrequencyToneDescription
Bedford County Police Dispatch 460.375 203.5 PL
Bedford County Police 453.475 203.5 PL Officer communications
Bedford County Police 453.575 203.5 PL Officer communications
Bedord County Sherrif 155.490 County Sheriff Interop
Bedford County Jail 460.45 Corrections Dept

County Fire

GroupFrequencyToneDescription
Bedford County Fire 33.74 Fire Dispatch
Bedford County Fire 33.72 Fireground
Hyndman VFC 33.78 Hyndman VFC
Bedford VFC 33.96 Fire Tactical
Blair County Dispatch 460.6 82.5 PL Interop
Blair County South 460.05 103.5 PL Interop

County EMS

GroupFrequencyToneDescription
EMS Dispatch 155.22 167.9 PL EMS Dispatch
Hyndman Rescue 155.28 Rescue Squad/Talk
Hyndman Rescue 155.34 Rescue Squad/Talk
STAT Medevac 155.265 103.5 PL STAT Medevac Helo Operations/Dispatch
Medstar Dispatch 155.34 107.2 PL Med Star Medeva Helo/Dispatch
Medic-4 463.075 136.5 PL EMS Med-4 /Hospital
Medic-6 463.125 136.5 PL
Medic-7 463.150 136.5 PL EMS Med-7 /Hostpital
Medic-8 463.175 136.5 PL EMS Med-8 /Hospital
Medic-10 463.975 136.5 PL Blair County Intersystem /Hospital Patch

State

Chaneysville (Bedford) 866.27500 868.48750

More Information

 

Understanding Amateur Radio

What is Amateur Radio?

Amateur Radio means many things to many people. However, first and foremost, it is a hobby. People get into amateur radio because they have found something in it that they enjoy. For some, it's the idea of being able to talk to someone half a world away without relying on any sort of infrastructure. A radio, a battery, and some wire will get you on the air. Others just want to talk to local friends on the repeater. Still others are into building things, and amateur radio is a great outlet for that. Up until recent years, “technical people” have been in the minority. Finding a diverse group of technically minded people to talk with has always been a challenge. Amateur Radio provides a medium for technical people to come across each other and enjoy a sense of community.

While there is a licensing test to take (involving technical questions and some legalese), the learning curve is not that hard. You see, Amateur Radio operators are granted the largest chunk of the wireless spectrum and given the most amount of freedom in how they can operate. A commercial radio station has to operate within very tight restrictions. Unlicensed operators must use FCC Part 90 certified low-power, “locked down” equipment. But in Amateur Radio, the onus is on the operator to ensure that they are within regulations. The test is in place to ensure that an aspiring operator understands what they are working with and the potential interference that they can cause.

Does this mean you have to be a technical genius in order to get into Amateur Radio? *Absolutely not!** The test requirements are designed to allow as many people as possible to get on the air. Children as young as 8-years old have studied for and passed the FCC License exam. Many Boy and Girl Scouts will seek out an amateur license as part of a merit badge requirement. Young, old, deaf, and blind people have taken and passed the test. What's a deaf person doing on the radio? Most likely they're participating in a digital mode such as Radio TeleType (RTTY). From voice communications to packet radio to talking with the Internation Space Station, Amateur Radio has just about something for everyone to enjoy.

 

HAM Etiquette

Amateur Radio is first and foremost a hobby to be enjoyed. In order to keep it as enjoyable as possible, operators have developed a code of conduct for operating that is in some ways more important than the FCC regulations. This common courtesy goes beyond “keeping it clean” and includes tenants such as leaving a pause for other operators to break in and managing “round table” type discussions.

More Information

 

Voice Communications

Simplex

Simplex Radio communications (sometimes referred to as half-duplex) is one of the most common and simplest form of communication. Operating simplex means that you are transmitting and receiving on the same frequency. Typically, only one transmitter is active at a time within a coverage area. Once the radio operator completes their transmission, they stop transmitting and allow other operators to respond with their own transmission. If two operators attempt to transmit at the same time, this is called doubling or getting stepped or walked on. If a lot of operators attempt to transmit at the same time on the same frequency, this is called a pile up.

The most prevalent and active use of simplex radio is probably CB channel 19. The bulk of CB radios sold in the US default to channel 19. On any given day near any given road, finding activity on channel 19 is not uncommon in the least.

For amateur radio in the US, the frequency 146.520 is reserved as the “National Simplex Calling Frequency”. Many ham radio operators monitor this frequency at home and while traveling. While activity on this frequency has been on the decline as linked repeater systems become more common, there is a concerted effort to make this channel more active once again. The Interstate Highway Rest Area Society1) is promoting an annual event for hams to operate out of rest area parking lots. This event (RAOTA)2) is to take place annually the weekend following Thanksgiving, the busiest travel period of the year.

More Information

Duplex and Repeaters

Repeaters typically work in two modes: simplex and duplex. A simplex repeater receives on one frequency, records what it receives, and then broadcasts it again on the same frequency once the original transmission stops. A duplex repeaters will listen on one frequency and transmit simultaneously on another. Duplex are the more common type of repeater as they allow for more continuous communication.

Some repeaters use a ”pl tone”(also called ctss or sub-audible) tone to reduce interference. With a PL Tone, the end-user transmits a pre-configured tone ranging from 67.0 Hz to 250.3 Hz along with their transmission. The repeater will only activate if it hears the appropriate tone. This prevents the repeater from keying up during spurious transmissions. The PL tone is removed from the final output audio of radios receiving the broadcast.

In order to use a duplex repeater, you need to understand how the frequencies work (though many new radios will have an “auto repeater” feature that figures this out automatically). We will use the BCARS “K3NQT” repeater for an example. Typically, a repeater is listed by its transmit frequency (Tx). BCARs 2M transmits on 145.490, so you would tune your radio to receive on 145.490 in order to hear it. However, the BCARs 2M repeaters listens on a “negative offset” frequency of 144.890 (0.6Mhz 'down' from 145.490). So in order for you to talk to the repeater, you need to program an offset into your radio so that it transmits on 144.890. While the procedure varies from radio to radio, it usually involves two settings: 1) the offset type of + (postive), - (negative), or “none” (simplex) AND 2) the offset spacing. For BCARS 2M, the offset spacing is 0.6Mhz. The BCARs repeaters also use a PL Tone of 123Hz, so you would have to enter that in as a separate setting.

Because there are a large number of possible offsets (or splits) that repeaters can use, a standard has been adopted within the US for repeater pairs.

On the 2-meter band, the offset spacing is typically 0.6Mhz. If the repeaters Tx frequency is below 147Mhz, the offset is typically negative. If the Tx Frequency is above 147 Mhz, the offset is typically positive.

Output Frequency Input Frequency Offset
51-52 - 0.5 MHz
52-54 - 1.0 MHz
144.51-144.89 + 0.6 MHz
145.11-145.49 - 0.6 MHz
146.0-146.39 +0.6 MHz
146.61-147.0 -0.6 MHz
147.0-147.39 +0.6 MHz
147.6-147.99 -0.6 MHz
223-225 - 1.6 MHz
440-445 + 5.0 MHz
445-450 - 5.0 MHz
918-922 -12 MHz
927-928 -25 MHz
 

Digital Modes

Digital Modes refer to any mode where you send information in a mode other than voice or video. Occasionally HAMs will include Morse Code as digital, but others will disagree as it can be understood by the human ear. Excluding Morse Code, digital typically requires a computer or microcontroller in order to send and receive the information.

There are three “popular” options. Real Time Digital mode (NBEMS/RTTY/PSK using fldigi), APRS, and Packet.

WPA ARES actively promotes using existing repeaters to send real-time digitial notices. It's not automated by any means. In this scenario, you would start off with voice, announce that you're going to send your digital message, wait for a voice “go ahead” and then send it.

Ideally, you would have at least person in the EOC (which would be the club room, if we had antennas) directing the emergency net with an ability to send and receive real-time digital. On the net, you would have to take turns between sending voice and sending digital. For this to work though, operators would need the fldigi program installed on their computer and for their computer to be able to hear the radio. While acoustically coupling works fairly good, a dedicated interface cable would definitely cut down on noise. If you have a computer with a soundcard, adding real-time digi takes only a bit of effort. I think we need to get more members setup with the fldigi software and perform a few practice NETs to give people practice.

Another option for short alerts is APRS (144.390 PL 100). There are a fair number of APRS users in our area and most of Bedford County is in reach of an APRS digipeater. Within the club itself however, not too many people have it. The club also doesn't have any form of APRS transmitter, though I am hoping to set one up. With APRS, you can send out bulletins that would get displayed on APRS capable radios (as well as PCs connected to an radio). We could send out bulletins such as “Tornado warning, emergency net on 145.490” and every APRS device in the area would receive it. An APRS compatible radio could even press a button and automatically tune one side of their dual-band radio to that frequency. APRS allows sending “public” broadcasts and you can send to individual operators by their call sign. Messages are limited to 3 lines of 67 characters each for a total of 201 characters. Shorter messages are better for propagation.

As a final option, there is packet. There are a couple BBSes in the area, such as N3NXO's MTDALLAS station on 145.05. This is a more dedicated mode with no room for voice. The advantage of using a BBS would be the CONVersation mode, which would be a form of text-based chat. Operators are able to connect to this BBS and drop into CONVerse mode to chat with other operators. You can also upload a file to a BBS and then others can download it. The Packet mode allows multiple operators to be transmitting text at once and the packet station will sort it all out and put the text in order. The big downside to packet compared to the other two modes is that it ties up a 2M radio. Even if you have a dual-vfo radio, one side of the radio is going to be monopolizing your antenna. However, if you have an older 2M radio without PL tones/repeater capabilities, it will make a good packet radio.

Somerset County has put together a really nice BBS infrastructure on 145.03. They have a couple packet stations deployed with a BBS to BBS “backbone” on 220Mhz.
http://www.k3smt.org/packet/index.shtml

 

Real-time digital

Using software such as fldigi, you can use your computer to send and receive digital data in various modes in-between voice transmissions. If you already have a computer with a sound, the cost to entry is very low. Your computer's sound card can convert text to sound and transmit it out the speakers. Conversely, you can feed the radio's audio output into the computer's microphone to receive these transmissions. The best setup would involve a push to talk adapter and a pair of audio cables connecting the computer to your radio. However, if your radio supports VOX (voice operated transmit), you don't actually need the PTT circuit. For really low end, some people have had good success just holding the radio near the speakers and microphone and manually pressing the radio's PTT!

How is this useful? HAM works on a one-to-many or a many-to-many approach. If you need to send a list of information - be it people's names, supplies needed, or model & serial numbers, voice is very, very slow and prone to error. How many times have you had to ask an operator to provide their call sign more than once. Using phonetics such as Kilo-Bravo-Three is even slower and *still* error-prone. By typing this list up on your computer before hand, you can paste it into fldigi and send it relatively error-free in one transmission. Since this is not a continuous digital mode, you can take turns between voice and digital. This means you can send digital transmissions using existing repeaters.

Here is the fdigi beginner's guide.

fdigi in action Setting up for FM use
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The Adobe Flash Plugin is needed to display this content.

fldigi also has several supporting programs.

  • flwrap converts a digital file such as a photograph or ZIP file into ascii data which can then be transmitted over the radio.
  • flsmg is a FORM manager that allows operators to fill out a standard form. You fill out the form in an easy to use graphical interface and then send it as pure ASCII. Receiving stations can view the raw text or open it in either their web browser or flmsg. The receiving station can then print out the form or email it from their computer if available. There are several forms included, but anyone can make their own form and distribute it locally. Not everyone needs the form on their computer to receive it (as the form will open in a web browser - no internet access needed). A standard form could be created just for Bedford County EMS if desired.
    • ICS-203 - Organization Assignment List
    • ICS-205 - Incident Radio Communictions Plan
    • ICS-205A - Comms List - special USCG Plan
    • ICS-206 - Medical Plan
    • ICS-213 - emergency management report
    • ICS-214 - Unit log
    • ICS-216 - Radio Requirements Worksheet
    • Radiogram - NTS message
    • Plaintext - generic message format
    • Blank - very simple text format with no preset fields
    • Drag and Drop - target control (widget) that accepts either a data file (.203 etc), a wrapped data file (.wrap), or the text associated with a data file. The later may be a copy and paste from another application such as fldigi or a text editor.

Comparison with Packet

Traditional packet operation typically requires a dedicated frequency. Packet stations perform beaconing and repeating of data, all under automatic control. It is quite common for multiple stations to transmit at the same time. There is no room for voice transmissions. “Real-time digitial” however, is manually controlled by human operators. There is typically a voice transmission in between each digital transmission. In essence, the data is controlled by voice. An operator getting ready to send will inform other operators of his intent. The receiving operator will announce they are ready “send your traffic” and if it was received properly “solid copy”.

Packet has its advantages. For instance messages can be sent from packet station to packet station automatically until it reaches its destination. A user of one node in Bedford, PA can send a message to a node in Warfodsburg, PA and be relatively confident that it will arrive within minutes. Packet nodes can also be used to send and receive email from the Internet at large (for example, using winlink). Packet BBSes often have what is known as a “CONVerse” mode where operators can “chat” in real-time on a channel.

However, packet has disadvantages in an emergency situation. First off, it excludes voice only operators. Second, since packet uses a “store and forward” method of sending messages between nodes, critical messages can be delayed minutes, hours, or even days (depending on how congested the channel is).

more information
 

APRS

Automatic Packet Reporting System

For quick reference, here are the common APRS frequencies and PL tones to use in the US:

Ch1 “APRS VA ” 144.39 Voice Alert, CTCSS 100 for normal operations
Ch2 “APRS raw” 144.39 no tone squelch - for troubleshooting
Ch3 “APRSmute” 144.39 CTCSS 123 - for completely QUIET operation (substitute any private CTCSS tone you want)

APRS is most commonly associated with just location, but it is a full-fledged messaging system for radio operators. You don't even need a GPS to utilize APRS. At its core, APRS is a standard packet format for short messages with limited distribution. If that sentence confuses you, follow this scenario.

  1. Operator 1 tunes his APRS-equipped radio to 144.39Mhz (pl tone 100hz) and uses the radios built in controls to tap out a text message “Route I-99 Mile 39 washed out”.
  2. This message is transmitted from his radio and picked up by 4 other radios within his transmitter range
  3. These radios display the message on their screen and then retransmit the message again
  4. Each message has a built-in limit as to how far it could be retransmitted, typically limited to 2 or 3 retransmits. This prevents the local message from being relayed across the US. It keeps the message relatively local, based on the transmit power of each radio involved.

APRS messages are used to identify radio resources within an area. If an operator is able to connect a GPS to their APRS radio (or a location-aware computer to a non-APRS enabled radio), they can provide their exact location. Web services exist to view APRS resources within an area and to send them messages directly. ARPS messages can also include items like the frequency pair of a local repeater. Imagine driving into a new area and getting a message with a suitable repeater to use. The mere act of receiving the message tells you that you are in range to hear the repeater.

Many amateurs will connect a laptop to their APRS radio (or you can connect one to an older single-band radio or HT) to be able to view and interact APRS information on a full screen (and keyboard). If GPS enabled APRS users are transmitting nearby, they can show up on a map. You can send messages to them directly.

APRS nodes also act as a relay. You can specify a specific call sign to send an APRS message to (even if you don't see them in your list) and your message will be relayed from APRS node to APRS node until it reaches its destination.

 

Packet

Packet data

bbses

winlink

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Satellite Communications

Most satellites transmit on 2M and receive on 440.

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Getting Your License

Also called a ticket…

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Get On The Air

There are numerous ways to get on the air and make contact.

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