Saturday, November 22, 2014

Amateur Radio in the 2014 National Emergency Communications Plan

DHS has published the 2014 update to the National Emergency Communications Plan (NECP) and it recommends greater cooperation beetween federal, state and local government agengies and with the Amateur Radio Service.

Source: Department of Homeland Security

The Amateur Radio Service is defined as "A radio communication service for the purpose of self-training, intercommunication, and technical investigations carried out by amateurs, who are duly authorized persons interested in radio technique solely with a personal aim and without pecuniary interest."

The NECP says that amateur radio operators "can be important conduits for relaying information to response agencies and personnel when other forms of communications have failed or have been disrupted."

"With assistance from DHS, State, local, tribal, and territorial jurisdictions should assess their existing governance structures to ensure they are positioned to address current and emerging policy, technology, and planning developments.  This could include adding representatives to Statewide Interoperability Governing Bodies and Statewide Interoperability Executive Committees from associations, organizations, or agencies that support or rely on communications during response and recovery operations (e.g., emergency management agencies, 9-1-1 boards, hospital associations, utilities, and amateur radio organizations)."

"Federal, State, local, tribal, and territorial jurisdictions should identify domestic and international entities with potential roles in information sharing and the delivery of emergency communications during emergencies (e.g., utility companies, amateur radio operators, nongovernmental organizations, media companies, and telecommunications owners, operators, manufacturers, and suppliers).  As appropriate, these entities should be incorporated into training and exercise activities on a more regular basis.  This includes involving the appropriate stakeholders in curriculum or exercise design and execution, as necessary."

"Likewise, volunteer organizations such as community emergency response teams and auxiliary communications volunteers (e.g., amateur radio operators; also called Hams) play key roles in emergency communications and preparedness.  Volunteer emergency communications operators and groups using amateur radio have been providing backup communications to event planners, public safety officials, and emergency managers at all levels of government for nearly 100 years.  Often, amateur radio services have been used when other forms of communications have failed or have been disrupted.  Today, nearly all the States and territories have incorporated some level of participation by amateur radio auxiliary communication operators into their Tactical Interoperable Communications Plans and Statewide Communication Interoperability Plans; this allows them to quickly integrate the operators into response efforts, which can strengthen communications and operations during incidents of any scale.

FCC:  Uses and Capabilities of Amateur Radio Service Communications in Emergencies and Disaster Relief

Sunday, November 16, 2014

Local officials say radio can fill in for Internet in event of cyber attack

Source: WBBTV

“We can actually send email attachments, video and what-not via ham radio without ever using the Internet.”

“Their contacts can be in the emergency operations center using their emails as they would on a daily basis.”

“The software can send the digital information via radio waves to another station with similar equipment and then be able to pull it up on the screen and print it out."

40th Anniversary of the Arecibo Message

Source: Slate

Nov. 16, 2014, marks the 40th anniversary of the Arecibo message, an interstellar communiqué transmitted from the Arecibo radio telescope in Puerto Rico toward Messier 13, a globular cluster of stars located more than 22,000 light-years away.

Saturday, November 15, 2014

Family Radio Service (FRS) - Types of communications

You may use an Family Radio Service (FRS) unit to transmit a brief text message to another specific FRS unit and automatically respond with location. Digital transmissions can be one second per thirty-second period and automatically respond to more than one interrogation request received within a thirty-second period.

Source: FCC

Code of Federal Regulations

Title 47 - Telecommunication

Volume: 5
Date: 2007-10-01
Original Date: 2007-10-01
Title: Section 95.193 - (FRS Rule 3) Types of communications.
Subpart B - Family Radio Service (FRS). - General Provisions.

§ 95.193(FRS Rule 3)

Types of communications.
(a) You may use an FRS unit to conduct two-way voice communications with another person. You may use an FRS unit to transmit one-way voice or non-voice communications only to establish communications with another person, send an emergency message, provide traveler assistance, provide location information, transmit a brief text message, make a voice page, or to conduct a brief test.
(b) Non-voice communications. 
     (1) The FRS unit may transmit tones to make contact or to continue communications with a particular FRS unit. If the tone is audible (more than 300 Hertz), it must be transmitted continuously no longer than 15 seconds at one time. If the tone is subaudible (300 Hertz or less), it may be transmitted continuously only while you are talking.
    (2) The FRS unit may transmit digital data containing location information, or requesting location information from one or more other FRS units, or containing a brief text message to another specific FRS unit. Digital data transmissions must be initiated by a manual action or command of a user, except that an FRS unit receiving an interrogation request may automatically respond with its location. Digital data transmissions shall not exceed one second, and shall be limited to no more than one digital transmission within a thirty-second period, except that an FRS unit may automatically respond to more than one interrogation request received within a thirty-second period.
(c) You must not use an FRS unit in connection with any activity which is against federal, state or local law.
(d) You must, at all times and on all channels, give priority to emergency communication messages concerning the immediate safety of life or the immediate protection of property.
(e) No FRS unit may be interconnected to the public switched network.

[61 FR 28768, June 6, 1996, as amended at 68 FR 9901, Mar. 3, 2003]

Thursday, October 9, 2014

AZ CO NM UT Four Corners area is hot spot for methane emissions

Source: NASA JPL

Image Credit: 

NASA/JPL-Caltech/University of Michigan

The Four Corners area (red) is the major U.S. hot spot for methane emissions in this map showing how much emissions varied from average background concentrations from 2003-2009 (dark colors are lower than average; lighter colors are higher).

The study's lead author, Eric Kort of the University of Michigan, Ann Arbor, noted the study period predates the widespread use of hydraulic fracturing, known as fracking, near the hot spot. This indicates the methane emissions should not be attributed to fracking but instead to leaks in natural gas production and processing equipment in New Mexico's San Juan Basin, which is the most active coalbed methane production area in the country.

Natural gas is 95-98 percent methane. Methane is colorless and odorless, making leaks hard to detect without scientific instruments.
"The results are indicative that emissions from established fossil fuel harvesting techniques are greater than inventoried," Kort said. "There's been so much attention on high-volume hydraulic fracturing, but we need to consider the industry as a whole.

Sunday, October 5, 2014

RBN - Reverse Beacon Network

Listening seems to be the most important part of ham radio. I'm feeling motivated to learn Morse Code.

Source: The Reverse Beacon Network

The Reverse Beacon Network is a revolutionary new idea. Instead of beacons actively transmitting signals, the RBN is a network of stations listening to the bands and reporting what stations they hear, when and how well.

Wednesday, September 17, 2014

SO-51 pass at 2014 Sep 17 03:01 UCT over Texas

Listen to a recording of the last pass of the Saudi‑OSCAR 50 (SO-50) amateur radio satellite which was launched on December 12, 2002 by the King Abdulaziz City for Science and Technology.

I copied the following operators' call signs:

KD8CAO Douglas Papay in Zeeland, MI USA

N8RO  Ronald Oldham in Comfort, TX USA

KM4AYE Robert Fudge in Athens, AL USA

KB1QYS  Paul Nichols in Uxbridge, MA USA

KM4CPJ  Jeff Bebber in Lutz, FL USA

W5PFG  Claytob Coleman in Palestine, TX USA

N5JF  Joseph Fouquet in Covington, LA USA

Saturday, September 13, 2014

Ham Speak: Terminology, Codes and Jargon Commonly Used in Amateur Radio

Ham radio operators often use thier own terminology, codes, acronyms and jargon while communicating.  It can be difficult to learn and remember all of the "ham speak" so I made a note of the terms I have heard most frequently on repeaters.  The etiquette for repeaters tends to involve the use of only plain English so that less experienced operators can understand.  Some of the more experienced operators sometimes to use jargon especially when communicating with other experienced operators.

IMPORTANT NOTE: Some words and phrases have very specific legal definitions and careful study of the FCC regulations is necessary in order to remain compliant with FCC rules.  For the purposes of simplicity I will avoid most of the finer details of FCC regulations and focus on the basic definitions of the terminology.

Terminology Related to Radio Equipment:

  • Station - An installation designed to provide radio communications in the amateur service, including all necessary equipment.
  • Portable station - A station that is carried in your hand and transmits low power through an antenna that is close to your body.
  • Mobile station
     - A station that is mounted in a vehicle and transmits high power through an antenna mounted on the roof or frame of the vehicle.
  • Fixed ground stationA station that is in a fixed location and typically cannot be easily moved to another location.
  • Temporary field stationA station that is in a fixed location during operation but can be moved to another location with some assembly and disassembly required.
  • Space station - A station at an altitude higher than 50 kilometers, usually a satellite in low earth orbit or at a higher geosynchronous orbit.
  • Auxiliary station - A station, such as a repeater, that is remotely controlled over a radio link.
  • Repeater station - A station that typically receives on one frequency and transmits on another frequency through a tall tower in order to extend the range of portable and mobile stations.
  • Rig - A generic term for a station that may be portable, mobile or fixed.
  • Transceiver - A radio device that can transmit and receive.
  • Parasitic element - Part of a directive antenna that derives energy from mutual coupling with the driven element. Parasitic elements are not connected directly to the feed line.
  • Monopole antenna - A straight rod-shaped conductor often mounted perpendicular to a conductive surface called a ground plane such as the roof of an automobile.
  • Dipole antenna - Two identical conductive elements such as metal wires or rods, which are usually bilaterally symmetrical.
  • Half-wave Dipole antenna - A dipole antenna with elements that are ½ the length of the wavelength at the desired operating frequency.
  •  J-pole antenna -  An end-fed dipole antenna that is matched to the feedline by a quarter wave transmission line stub.
  • Beam antenna - A directional antenna that must be rotated toward the direction of the receiving station or repeater.
  • Yagi antenna - The most popular type of beam antenna that has one driven element and one or more additional parasitic elements.
  • Base loading coil - A coil at the bottom of an antenna to achieve a lower resonant frequency.  Some mobile antennas have a stepping motor to adjust the length of the loading coil for use on many bands.

Terminology Related to Station Configuration and Operation:
  • Call sign - Series of unique letters and numbers assigned to a person who has earned an Amateur Radio license and his or her station.
  • Control operator -- An amateur operator designated by the licensee of a station to be responsible for the transmissions of an amateur station.
  • Band - A range of frequencies that share a similar wavelength.
  • Simplex operation - Receiving and transmitting on the same frequency.
  • Duplex operation - Receiving on one frequency and transmitting on another frequency.
  • Squelch - A circuit that mutes the receiver when no signal is present, thereby eliminating band noise.
  • Offset - The difference between transmit and receive frequencies.
  • Continuous Tone Coded Squelch System (CTCSS) - A method of using low frequency subaudible tones to share a single radio channel among multiple users.  Each user group would use a different low frequency tone.  CTSS is commonly used in repeater systems to prevent opening the squelch unless a radio is configured with the correct tone frequency.
  • Private Line (PL) - A term trademarked by Motorola to describe their implementation of CTSS.  PL seems to be the most commonly used generic term for CTSS.
  • Channel Guard (CG) - General Electric used this term to describe their implementation of CTSS.
  • Courtesy tone - A tone or beep transmitted by a repeater to indicate that it is okay for the next station to begin transmitting. The courtesy tone is designed to allow a pause between transmissions on a repeater, so other stations can call. It also indicates that the time-out timer has been reset.
  • Sideband - The sum or difference frequencies generated when an RF carrier is mixed with an audio signal.
  • Single-sideband (SSB) - SSB transceivers allow operation on either USB or LSB
  • Upper sideband (USB) -- Upper sideband is the part of the signal above the carrier and is the SSB operating mode used on on the 20, 17, 15, 12 and 10-meter HF amateur bands, and all the VHF and UHF bands
  • Lower sideband (LSB) -- Lower sideband is the part of the signal below the carrier.
  • Peak envelope power (PEP) - The average power of a signal at its largest amplitude peak.
  • Effective Radiated Power (ERP) - A standardized theoretical measurement of radio frequency  energy determined by subtracting system losses and adding system gains.
  • Duty cycle - A measure of the amount of time a transmitter is operating at full output power during a single transmission.

Abbreviations and Codes: 

  • 73 - best regards. 
  • 88 - Love and kisses.
  • APRS - Automatic Packet Position Reporting System is used to send your GPS coordinates, elevation, along with an optional brief text message and other information such as weather conditions.
  • ARES - Amateur Radio Emergency Service is a group organized by the ARRL including volunteers who are prepared to relay emergency traffic and cooperate with FEMA and other government agencies.
  • ARRL - American Radio Relay League is the national amateur radio organization in the USA.
  • CC&R's - Covenents, Conditions, and Restrictions are rules drawn up by homeowner's associations that often prohibit certain types and sizes of antennas.
  • CQ - "Calling any station": the general call when requesting a conversation with anyone. 
  • CW - Continuous wave mode transmitted by on/off keying of a radio-frequency signal. Another name for international Morse code.
  • DE - The Morse code abbreviation for "from" or "this is."
  • DX - A distant station (noun) or to contact a distant station (verb)
  • HF - High Frequency from 3 MHz to 30 MHz
  • HT - Handie-talkie more properly known as a portable station.
  • LF - Low Frequency from 30 kHz to 300 kHz
  • OSCAR - Orbiting Satellite Carrying Amateur Radio.
  • PSK31 - A digital transmission mode using Phase Shift keying with a 31.25 baud rate.
  • PTT - Push to Talk is a button that activates the transmitter.
  • Q signals - Three-letter symbols used on CW to save time and to improve communication.
  • QTH - location
  • QSO - conversation
  • QSL - acknowledgment of receipt
  • QSL card -- A postcard that serves as a confirmation of communication between two hams.
  • QRL - "Is this frequency in use?" or "This frequency is in use."
  • QRP - Low power operation, usually 5 watts output or 10 watts input power.
  • QSO - A conversation between two radio amateurs.
  • RACES - Radio Amateur Civil Emergency Service is a group of volunteers who are prepared to relay emergency traffic and cooperate with FEMA and other government agencies.
  • SQL - Squelch is a circuit that mutes the receiver when no signal is present, thereby eliminating band noise.
  • UHF - Ultra High Frequency from 300 MHz to 3000 MHz
  • VE - Volunteer Examiner, a person authorized to administer examinations for amateur radio licenses.
  • VFO - Variable Frequency Oscillator more commonly known as the tuning nob.
  • VHF - Very High Frequency from 30 MHz to 300 MHz
  • VLF - Very Low Frequency from 3 KHz to 30 KHz
Jargon and Slang:
  • Bacon frying - Slang for static heard in a transmission.
  • Clear - Used to indicate a station is done transmitting and the repeater is free for use by other operators.
  • Copy - Indication of how well communications are received such as"how do you you copy?" and "copy all."
  • Destinated - Slang for "I have reached my destination" commonly used by mobile operators to indicate that they need to end the conversation.
  • Echolink - Use of Voice over IP (VoIP) to connect repeaters over the internet.
  • Eyeball QSO - Conversations that occur in person rather than over the radio.
  • Farm - Many antennas mounted in close proximity.
  • Fox hunt - A method of locating the source of a transmission often used in a contest to locate a hidden transmitter or a station that is causing interference or operating in violation of FCC rules.
  • Full quieting - A phenomenon on FM transmissions where the incoming signal is sufficient to engage the receiver limiters - thus eliminating the noise due to amplitude fluctuations.
  • Green stamp - One to two US dollar bills sent along with a QSL card to cover postage costs of a return card.  This is a common courtesy especially for contacts with operators in the third-world.
  • Key - A switch or button (noun) usually refers to the PTT or Morse code key or to press (verb) a key or button.  Also when you "key up" a repeater you have pressed your PTT and sent the correct PL tone to the receiving frequency of the repeater.
  • Machine - A station, usually a repeater.
  • Net - A gathering of operators organized for a particular purpose on a regular schedule and frequency.  Nets encourage operators to join in conversation with operators with whom they are not familiar and also helps ensure the proper functionality of equipment such as repeaters and stations.
  • Over - Used to turn over communications under difficult copy. Note, repeater etiquette discourages the use of "over" as repeaters usually have a courtesy tone that service this purpose.
  • Picket fencing - A condition experienced on VHF and above where a signal rapidly fluctuates in amplitude causing a fluttering sound akin to rubbing a stick on a picket fence.
  • Rag Chew - An extended and informal conversation between two operators.  This is likely derived from a variation of the common idioms "chewing the fat" and "chewing the rag".
  • Rubber duck - A shortened flexible antenna used with hand-held scanners and transceivers.
  • Shack - Slang for the room where an operator keeps his or her station equipment.
  • Time-out - Excessively long transmission on a repeater causing the repeater’s timer circuit to stop further transmissions.
  • Wallpaper - QSL cards, awards and special event certificates mounted on the shack wall.
  • Work - To communicate with another radio station, repeater and/or satellite.
Terminology Related to Prioritization of Emergency Radio Communications:

  • National Traffic System (NTS) - A network of amateur radio operators organized by areas that approximate time zones, regions and sections that correspond to states or metropolitan areas.  The purpose of the NTS is to relay messages throughout the US and Canada.
  • Traffic - Messages and communications that are transmitted over the amateur service.
  • Emergency traffic - Messages involving threat to life or property.  Emergency traffic is sent by any means necessary and most FCC rules provide exceptions for emergency traffic.
  • Priority traffic - Emergency-related messages that do not involve threat to life or property and are not as important as Emergency traffic.
  • Welfare traffic - Messages related to the heath and well being of individuals in a disaster area. Such messages must wait for Emergency and Priority traffic to clear, and results in advisories to those outside the disaster area awaiting news from family and friends.
  • Routine traffic - Most messages will bear the lowest priority designation of routine traffic. In disaster situations, routine traffic should be handled last. Routine traffic should never be relayed when circuits are busy with higher-precedence traffic.  The NTS practices the relay of routine traffic several times per day in order to build the competence and confidence of volunteer operators.

Signal Reports in Ham Radio

Signal reports are sometimes requested by operators who are testing a radio. Sometimes friendly operators will offer a signal report even if you don't ask for one. I usually get an unsolicited signal report if it is difficult to copy my voice transmission through a repeater.
The etiquette when using a repeater seems to be using plain English. So you might give or receive signal reports such as "I can hear you just fine", "your voice sounds strange" or "I can barely hear you and there is a lot of static". Problems with your transmission will often be followed by questions about your radio, its configuration and advice about how you may be able to improve your signal and readability.
Communication over great distances usually involve a more nerdy signal report with two or more numbers and maybe letters.
Source: ARRL
The RST System:
  1. Unreadable
  2. Barely readable, occasional words distinguishable.
  3. Readable with considerable difficulty.
  4. Readable with practically no difficulty.
  5. Perfectly readable.
    Signal Strength
  1. Faint signals, barely perceptible.
  2. Very weak signals.
  3. Weak signals.
  4. Fair signals.
  5. Fairly good signals.
  6. Good signals.
  7. Moderately strong signals.
  8. Strong signals.
  9. Extremely strong signals.
  1. Sixty cycle a.c or less, very rough and broad.
  2. Very rough a.c., very harsh and broad.
  3. Rough a.c. tone, rectified but not filtered.
  4. Rough note, some trace of filtering.
  5. Filtered rectified a.c. but strongly ripple-modulated.
  6. Filtered tone, definite trace of ripple modulation.
  7. Near pure tone, trace of ripple modulation.
  8. Near perfect tone, slight trace of modulation.
  9. Perfect tone, no trace of ripple or modulation of any kind.
If the signal has the characteristic steadiness of crystal control, add the letter X to the RST report. If there is a chirp, the letter C may be added to so indicate. Similarly for a click, add K. The above reporting system is used on both cw and voice, leaving out the "tone" report on voice.

Wednesday, August 13, 2014

Ham Radio Repeaters Connected via EchoLink

I was testing my radio with some local repeaters and one of the friendly hams said my signal was pretty clear but that he was on EchoLink and couldn't be sure. That reminded me of a question in the Technician class test pool:

"How is access to an IRLP node accomplished?
B. By using DTMF signals"

Then I googled EchoLink and connected my radio. The process is really simple:

1) Enter a frequency (MHz) and tone (Hz) into my ham radio tranceiver
2) Press and hold the push to talk (PTT) button
3) Enter a node number using the keypad
4) Release the PTT button

This "telecommand" controls a  repeater near me to connect across the Internet to a repeater in another city. The remote repeater will announce that is has connected and then I hold my PTT and chat with operators in the remote city.

Apparently I can also download applications and connect directly from a computer or smartphone to a remote repeater. So it's not really even necessary to buy a radio to make use of your license. Things sure have changed since my grandpa showed me how he used his radio when I was young.

For future reference, I listed a few examples of the repeaters nearby and near friends and family.


K5AMM-R Fort Worth  441.675 MHz 110.9 Hz Node 463758
KM5HT-R Hurst ARC 442.850 MHz 110.9 Hz Node 549691
WA5CKF-R Irving 146.720 MHz 110.9 Hz Node 634042
WD5RP-L Arlington, TX 145.560 MHz no tone Node 215788
NB7C-L Boise, ID 902.112 MHz Node 93417
N6MEF-R Santa Clara, CA Node 799194 927.838 MHz 100.0 Hz
KA6TGI-R San Francisco bay Node 68042 144.000 MHz 67.0 Hz
K7LER-R West Seattle Node 4515 441.800 MHz 141.3 MHz
K7RPT-R PORTLAND OR Node 758452 147.380 MHz 100.0 Hz

VA3UN-L Newmarket, ON Node 87273 
442.600 MHZ103.5 Hz
VE3RAK-R Toronto Ont Node 12068 444.700 MHz 103.5 Hz

US Amateur Radio Frequency Allocations for Technician class

The FCC has many regulations related to amateur radio operation and I copied a few notes hare for future reference. As part of my studies, I read FCC part 97 and it's impossible to remember everything. So I found that copying the most relevant regulations helps me quickly access the ones that apply to my Technician class license privileges preferences and location.

Please do your own homework and assume that some of the privileges listed below may not apply. I tried to delete everything about General and Extra class licenses so that I can quickly decide what I am allowed to do.

Source: ARRL

Technician licensees have limited privileges below 30 MHz.

At all times, transmitter power must be the minimum necessary to carry out the desired communications. Unless otherwise noted, the maximum power output is 1500 watts PEP. Technicians are limited to 200 watts PEP on HF bands. Geographical power restrictions apply to the 70 cm, 33 cm and 23 cm bands; see The FCC Rule Book for details.

80 Meters
3.525-3.600 MHz: CW Only

40 Meters
7.025-7.125 MHz : CW only

15 Meters
21.025-21.200 MHz: CW Only

10 Meters
Maximum power 200 watts PEP
28.000-28.300 MHz: CW, RTTY/Data
28.300-28.500 MHz: CW, Phone

28.000-28.070 CW
28.070-28.150 RTTY
28.150-28.190 CW
28.200-28.300 Beacons
28.300-28.500 Phone
6 Meters
50.0-50.1 MHz: CW Only
50.1-54.0 MHz: CW, Phone, Image, MCW, RTTY/Data

50.0-50.1 CW, beacons
50.060-50.080 beacon subband
50.1-50.3 SSB, CW
50.10-50.125 DX window
50.125 SSB calling
50.3-50.6 All modes
50.6-50.8 Nonvoice communications
50.62 Digital (packet) calling
50.8-51.0 Radio remote control (20-kHz channels)
51.0-51.1 Pacific DX window
51.12-51.48 Repeater inputs (19 channels)
51.12-51.18 Digital repeater inputs
51.5-51.6 Simplex (six channels)
51.62-51.98 Repeater outputs (19 channels)
51.62-51.68 Digital repeater outputs
52.0-52.48 Repeater inputs (except as noted; 23 channels)
52.02, 52.04 FM simplex
52.2 TEST PAIR (input)
52.5-52.98 Repeater output (except as noted; 23 channels)
52.525 Primary FM simplex
52.54 Secondary FM simplex
52.7 TEST PAIR (output)
53.0-53.48 Repeater inputs (except as noted; 19 channels)
53.0 Remote base FM simplex
53.02 Simplex
53.1, 53.2, 53.3, 53.4 Radio remote control
53.5-53.98 Repeater outputs (except as noted; 19 channels)
53.5, 53.6, 53.7, 53.8 Radio remote control
53.52, 53.9 Simplex
53.490-53.530 MHz:

2 Meters
144.0-144.1 MHz: CW Only
144.1-148.0 MHz: CW, Phone, Image, MCW, RTTY/Data

144.00-144.05 EME (CW)
144.05-144.10 General CW and weak signals
144.10-144.20 EME and weak-signal SSB
144.200 National calling frequency
144.200-144.275 General SSB operation
144.275-144.300 Propagation beacons
144.30-144.50 New OSCAR subband
144.50-144.60 Linear translator inputs
144.60-144.90 FM repeater inputs
144.90-145.10 Weak signal and FM simplex
145.01,03,05,07,09 are widely used for packet
145.10-145.20 Linear translator outputs
145.20-145.50 FM repeater outputs
145.50-145.80 Miscellaneous and experimental modes
145.80-146.00 OSCAR subband
146.01-146.37 Repeater inputs
146.40-146.58 Simplex
146.52 National Simplex Calling Frequency
146.61-146.97 Repeater outputs
147.00-147.39 Repeater outputs
147.42-147.57 Simplex
147.60-147.99 Repeater inputs

Notes: The frequency 146.40 MHz is used in some areas as a repeater input. This band plan has been proposed by the ARRL VHF-UHF Advisory Committee.

1.25 Meters
222.00-225.00 MHz: CW, Phone, Image, MCW, RTTY/Data

222.0-222.150 Weak-signal modes
222.0-222.025 EME
222.05-222.06 Propagation beacons
222.1 SSB & CW calling frequency
222.10-222.15 Weak-signal CW & SSB
222.15-222.25 Local coordinator's option; weak signal, ACSB, repeater inputs, control
222.25-223.38 FM repeater inputs only
223.40-223.52 FM simplex
223.52-223.64 Digital, packet
223.64-223.70 Links, control
223.71-223.85 Local coordinator's option; FM simplex, packet, repeater outputs
223.85-224.98 Repeater outputs only

The FCC has allocated 219-220 MHz to amateur use on a secondary basis. This allocation is only for fixed digital message forwarding systems operated by all licensees except Novices. Amateur operations must not cause interference to, and must accept interference from, primary services in this and adjacent bands. Amateur stations are limited to 50 W PEP output and 100 kHz bandwidth. Automated Maritime Telecommunications Systems (AMTS) stations are the primary occupants in this band. Amateur stations within 398 miles of an AMTS station must notify the station in writing at least 30 days prior to beginning operations. Amateur stations within 50 miles of an AMTS station must get permission in writing from the AMTS station before beginning operations. The FCC requires that amateur operators provide written notification including the station's geographic location to the ARRL for inclusion in a database at least 30 days before beginning operations. See Section 97.303(e) of the FCC Rules.

70 Centimeters
 420.0-450.0 MHz: CW, Phone, Image, MCW, RTTY/Data

420.00-426.00 ATV repeater or simplex with 421.25 MHz video carrier control links and experimental
426.00-432.00ATV simplex with 427.250-MHz video carrier frequency
432.00-432.07 EME (Earth-Moon-Earth)
432.07-432.10 Weak-signal CW
432.10 70-cm calling frequency
432.10-432.30 Mixed-mode and weak-signal work
432.30-432.40 Propagation beacons
432.40-433.00 Mixed-mode and weak-signal work
433.00-435.00 Auxiliary/repeater links
435.00-438.00 Satellite only (internationally)
438.00-444.00 ATV repeater input with 439.250-MHz video carrier frequency and repeater links
442.00-445.00 Repeater inputs and outputs (local option)
445.00-447.00 Shared by auxiliary and control links, repeaters and simplex (local option)
446.00 National simplex frequency
447.00-450.00 Repeater inputs and outputs (local option)

33 Centimeters
 902.0-928.0 MHz: CW, Phone, Image, MCW, RTTY/Data

23 Centimeters
1240-1300 MHz: CW, Phone, Image, MCW, RTTY/Data

Higher Frequencies:
2300-2310 MHz
2390-2450 MHz
3300-3500 MHz
5650-5925 MHz
10.0-10.5 GHz
24.0-24.25 GHz
47.0-47.2 GHz
76.0-81.0 GHz*
122.25 -123.00 GHz
134-141 GHz
241-250 GHz
All above 300 GHz

* Amateur operation at 76-77 GHz has been suspended till the FCC can determine that interference will not be caused to vehicle radar systems

Tuesday, August 12, 2014

Amateur Radio Technician Class license test study notes

I wanted to share some of my study notes from the Technician Class Amateur Radio license test. There is a lot of information that might be of interest to the geeks out there.

Today I was granted my license from the FCC and my call sign is KG5DMX.

Source: The No-Nonsense Technician-Class License Study Guide (for tests after July 1, 2014)

Note: The complete pool of multiple choice test questions can be found at I also used an Android App called Ham Test Prep to practice answering questions.

Q. What types of international communications are permitted by an FCC-licensed amateur station?

  A. Communications incidental to the purposes of the amateur service and remarks of a personal character

Q. What name is given to an amateur radio station that is used to connect other amateur stations to the Internet?
  A. Gateway

Q. What is the Internet Radio Linking Project (IRLP)?

  A. A technique to connect amateur radio systems, such as repeaters, via the Internet using Voice Over Internet Protocol For more reliable long-distance communications, amateurs use the HF frequencies.

For more reliable long-distance communications, amateurs use the HF frequencies. UHF signals are often more effective from inside buildings than VHF signals because the shorter wavelength allows them to more easily penetrate the structure of buildings. (T3A02)

horizontal antenna polarization is normally used for long-distance weak-signal CW and SSB contacts using the VHF and UHF bands. (T3A03)

The primary advantage of single sideband over FM for voice transmissions is that SSB signals have narrower bandwidth. (T8A07)

The approximate bandwidth of a single sideband voice signal is 3 kHz. (T8A08)

The approximate bandwidth of a VHF repeater FM phone signal is between 10 and 15 kHz. (T8A09)

Morse Code, or CW, is the type of emission that has the narrowest bandwidth. (T8A05)

The approximate maximum bandwidth required to transmit a CW signal is 150 Hz. (T8A11)

International Morse is the code used when sending CW in the amateur bands. (T8D09)

All of these choices are correct when talking about instruments used to transmit CW in the amateur bands (T8D10):

Straight Key
  Electronic Keyer
Computer Keyboard

Some modes have very wide bandwidths. The typical bandwidth of analog fast-scan TV transmissions on the 70 cm band, for example, is about 6 MHz. (T8A10)

The type of transmission indicated by the term NTSC is an analog fast scan color TV signal. (T8D04)

Digital modes: packet, PSK31 When hams talk about “digital modes,” we are talking about modes that send digital data rather than voice or other types of analog signals, such as television. Usually, we connect our transceivers to a computer to modulate and demodulate the digital signals, but some newer transceivers can do this internally.

All of these choices are correct (examples of a digital communications method) (T8D01):


Packet radio was one of the first digital modes. It is called packet radio because the data to be sent from station to station is separated into a number of packets which are then sent separately by the transmitting station and received and re-assembled by the receiving station.

All of these choices are correct when talking about what may be included in a packet transmission (T8D08):

  A check sum which permits error detection
  A header which contains the call sign of the station to which the information is being sent Automatic repeat request in case of error

Some amateur radio digital communications systems use protocols which ensure error-free communications. One such system is called an automatic repeat request, or ARQ, transmission system. An ARQ transmission system is a digital scheme whereby the receiving station detects errors and sends a request to the sending station to retransmit the information. (T8D11)

APRS is one service that uses packet radio. The term APRS means Automatic Packet Reporting System. (T8D02)

A Global Positioning System receiver is normally used when sending automatic location reports via amateur radio. (T8D03)

Providing real time tactical digital communications in conjunction with a map showing the locations of stations is an application of APRS (Automatic Packet Reporting System). (T8D05)

A popular digital mode on the HF bands is PSK. The abbreviation PSK means Phase Shift Keying. (T8D06)
PSK31 is a low-rate data transmission mode. (T8D07)

The “31” in PSK31 comes from the fact that data is transmitted and received at about 31 baud and that the bandwidth of a PSK31 signal is only about 31 Hz.

Separate eight-foot long ground rods for each tower leg, bonded to the tower and each other is considered to be a proper grounding method for a tower. (T0B08)

When installing devices for lightning protection in a coaxial cable feedline, ground all of the protectors to a common plate which is in turn connected to an external ground. (T0A07)

The maximum power level that an amateur radio station may use at VHF frequencies before an RF exposure evaluation is required is 50 watts PEP at the antenna. (T0C03)

the human body absorbs more RF energy at some frequencies than at others. (T0C05)

The 50 MHz band has the lowest Maximum Permissible Exposure limit. (T0C02)

To reduce RF current flowing on the shield of an audio cable (or in a power supply cable), you would use a ferrite choke. (T4A09)

Flat strap is the type of conductor that is best to use for RF grounding. (T4A08)

One thing that would reduce ignition interference to a receiver is to turn on the noise blanker. (T4B05)

Another common setting on VHF/ UHF transceivers is the offset frequency. This is especially important when operating repeaters. The common meaning of the term “repeater offset” is the difference between the repeater’s transmit and receive frequencies. (T4B11)

Many, if not most, new amateurs buy a hand-held transceiver, usally called an “HT,” as their first transceiver. One disadvantage of using a hand-held transceiver is that the maximum output power is generally only 5 W, and because of this, they have limited range. To increase the low-power output of a handheld transceiver, and therefore its, range, you can use an RF power amplifier. (T7A10)

Operating Procedures FM Operation Once they get their licenses, most Technicians purchase a VHF/ UHF FM transceiver. This type of radio allows them to use repeaters and participate in public-service events. A repeater station is the type of amateur station that simultaneously retransmits the signal of another amateur station on a different channel or channels. (T1F09)

Auxiliary, repeater, or space stations amateur stations can automatically retransmit the signals of other amateur stations. (T1D07)

To use repeaters, you need to know how to set up your radio. Repeaters receive on one frequency and transmit on another. You program your radio so that it receives on the repeater’s transmit frequency and transmits on the repeater’s receive frequency. The difference between the transmit frequency and receive frequency is called the repeater frequency offset. Plus or minus 600 kHz is the most common repeater frequency offset in the 2 meter band. (T2A01)

Plus or minus 5 MHz is a common repeater frequency offset in the 70 cm band. (T2A03)

Repeater operation is called duplex operation because you’re transmitting and receiving on two different frequencies. When the stations can communicate directly without using a repeater, you should consider communicating via simplex rather than a repeater. (T2B12)

Simplex communication is the term used to describe an amateur station that is transmitting and receiving on the same frequency. (T2B01)

To help amateurs operating simplex find one another, frequencies on each band have been set aside as “national calling frequencies.” 446.000 MHz is the national calling frequency for FM simplex operations in the 70 cm band. (T2A02)

146.52 MHz is the national calling frequency for FM simplex operation in the 2 m band.

Because repeaters often operate in environments where there is a lot of interference they are programmed not to operate unless the station they are receiving is also transmitting a sub- audible tone of a specific frequency. These tones are sometimes called PL (short for “private line”) tones or CTCSS (short for “continuous tone-coded squelch system”) tones. CTCSS is the term used to describe the use of a sub-audible tone transmitted with normal voice audio to open the squelch of a receiver. (T2B02)

If your radio has not been programmed to transmit the proper sub-audible tone when you transmit, the repeater will not repeat your transmission.

All of these choices are correct when talking about common problems that might cause you to be able to hear but not access a repeater even when transmitting with the proper offset: (T2B04)
  • The repeater receiver requires audio tone burst for access
  • The repeater receiver requires a CTCSS tone for access
  • The repeater receiver may require a DCS tone sequence for access

One of the controls on a VHF/ UHF transceiver is the squelch control. Carrier squelch is the term that describes the muting of receiver audio controlled solely by the presence or absence of an RF signal. (T2B03)

Saturday, August 9, 2014

Google Boosts Secure Sites in Search Results

This is great news! Google adjusted their ranking algorithms to favor (ever so slightly) sites that support HTTPS.

Source: Google via Electronic Frontier Foundation

"... we’d like to encourage all website owners to switch from HTTP to HTTPS to keep everyone safe on the web."

Wednesday, August 6, 2014

Rosetta arrives at comet destination

Source: ESA via Space Fellowship

NavCam animation 6 August. Copyright ESA/Rosetta/Navcam

“After ten years, five months and four days travelling towards our destination, looping around the Sun five times and clocking up 6.4 billion kilometres, we are delighted to announce finally ‘we are here’,” says Jean-Jacques Dordain, ESA’s Director General.

“Europe’s Rosetta is now the first spacecraft in history to rendezvous with a comet, a major highlight in exploring our origins. Discoveries can start.”
“Over the next few months, in addition to characterising the comet nucleus and setting the bar for the rest of the mission, we will begin final preparations for another space history first: landing on a comet,” says Matt.
“Arriving at the comet is really only just the beginning of an even bigger adventure, with greater challenges still to come as we learn how to operate in this unchartered environment, start to orbit and, eventually, land,” says Sylvain Lodiot, ESA’s Rosetta spacecraft operations manager.
“After landing, Rosetta will continue to accompany the comet until its closest approach to the Sun in August 2015 and beyond, watching its behaviour from close quarters to give us a unique insight and realtime experience of how a comet works as it hurtles around the Sun.”

Saturday, June 14, 2014

A tiny technical change in iOS 8 could stop marketers spying on you

The original source of this article appears to be WWDC session 715, "User Privacy on iOS and OS X," presented by Apple Product Security and Privacy representatives David Stites and Katie Skinner.

Source: Quartz

Whenever you walk around a major Western city with your phone’s Wi-Fi turned on, you are broadcasting your location to government agencies, marketing companies and location analytics firms.
At the core of such tracking is the MAC address, a unique identification number tied to each device. Devices looking for a Wi-Fi network send out their MAC address to identify themselves. 
Apple’s solution, as discovered by a programmer, is for iOS 8, the new operating system for iPhones which will be out later this year, to generate a random MAC addresses while scanning for networks. 

Thursday, May 29, 2014

We Are Now In Command of the ISEE-3 Spacecraft

Hooray for the nerds who made contact with a NASA probe that has survived well beyond its planned mission!
The International Sun-Earth Explorer (ISEE-3) is a spacecraft that was launched in 1978 to study Earth's magnetosphere and repurposed in 1983 to study two comets. Since 1983 the ICEE-3 probe has been traveling in a heliocentric orbit slightly faster than Earth and it will return close to Earth in August.  NASA has insufficient funding to communicate with ICEE-3 and therefore gave a private project team permission to communicate and control the probe.
Donations helped fund the project and the Arecibo Observatory in Puerto Rico was updated with a Software Defined Radio and a custom-made amplifier. Today the team was successful in communicating with the probe and they believe that they can order the probe to burn a thruster and move into orbit near earth until it can later be directed to observe a comet.

Source: Space College

By Keith Cowing on May 29, 2014 4:07 PM

The ISEE-3 Reboot Project is pleased to announce that our team has established two-way communication with the ISEE-3 spacecraft and has begun commanding it to perform specific functions. Over the coming days and weeks our team will make an assessment of the spacecraft's overall health and refine the techniques required to fire its engines and bring it back to an orbit near Earth.

First Contact with ISEE-3 was achieved at the Arecibo Radio Observatory in Puerto Rico. We would not have been able to achieve this effort without the gracious assistance provided by the entire staff at Arecibo. In addition to the staff at Arecibo, our team included simultaneous listening and analysis support by AMSAT-DL at the Bochum Observatory in Germany, the Space Science Center at Morehead State University in Kentucky, and the SETI Institute's Allen Telescope Array in California.

Of course this effort would not have been possible without the assistance of NASA and the Space Act Agreement crafted by NASA Headquarters, NASA Ames Research center, and the System Solar System Exploration Research Virtual Institute (SSERVI).