Emergency Communications (EmComm)

Cells and Batteries

AF5NP Battery, Cell, Emergency Communications (EmComm), Power, Primary, Rechargeable

Batteries are quite important to radio amateurs, especially when working portable or when using handheld transceivers.  There are a number of US license exam questions on the subject and hams should have a fair understanding of batteries and how they are used in amateur radio.

Figure T-1
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Let’s start with some terminology.  A battery is a collection of electrochemical (galvanic) cells connected in series (greater voltage) or parallel (more current) for a given application. The schematic symbol above hints that there is more than one cell in series to represent a generic battery. More on cells vs batteries at the end of this post.

There are various battery types and many battery sizes but for all applications–not just ham radio–there are two basic kinds of battery: Primary and Secondary.

Primary batteries are used once, then disposed of (non-rechargeable). Years ago these were mainly carbon-zinc composition but today we find alkaline and lithium give better performance and are more commonly used, along with smaller coin cell silver oxide and mercury compositions. The advantages of primary batteries or cells over secondary ones are higher energy per unit, longer storage times, and instant readiness.

Secondary batteries are rechargeable, which is their only real advantage over primary batteries. The most common rechargeable battery technologies today are lead-acid, Nickel-Cadmium, Nickel-Metal Hydride and Lithium-ion, and all are used in ham radio.

What does this really mean for hams?

Many years ago, radios used vacuum tubes (electron valves) and required multiple high voltages. Two or three different dry cell batteries were used, often wired in series, and they had to be replaced frequently. Be glad those days are long gone.

Nowadays modern ham radio gear runs off 12V DC power or lower, and there are occasions to use either primary or secondary batteries. Generally, secondary (rechargeable) batteries are preferred most of the time. The typical handheld transceiver (HT) comes with a rechargeable battery pack. Working portable HF or VHF/UHF with no AC power requires a battery, and this is almost always a secondary unit (lead-acid or Lithium-ion brick).

One instance where non-rechargeable (primary) batteries is smart is when using a HT in an emergency situation where there is no power or facility to recharge the unit. You can buy accessory primary battery packs for many HTs. It’s a good idea to keep one of these available along with spare alkaline or lithium cells in your go-kit for a real-life EmComm scenario. AA cells can almost always be purchased or scrounged in an emergency.

HT with stock rechargeable battery (7.2V) on right, AA pack (6×1.5=9V) on left

The lead-acid battery is still a primary reference in ham radio, largely because it is a vehicle’s power source for starting engines and powering on-board electronics (including mobile ham radio equipment). In fact, the 12V power standard for most modern ham gear derives from the car battery and is really 12.6V nominal with 13.6V standard level as when a car’s alternator is running to charge the lead-acid battery. That’s why ham radio 12V DC power supplies typically run around 13.5 to 13.8V; our equipment is designed for in-vehicle operation with a running engine.

12V lead-acid batteries for non-vehicle use often are sealed (SLA) with a gel electrolyte instead of liquid, making them less hazardous to handle and store. Absorbent glass mat (AGM) batteries are a similar variant of the lead-acid battery. All of these tend to deplete at around 10.5V. Draining the battery below this level may compromise its ability to fully re-charge, and possibly damage the battery.

The main advantages of lead-acid batteries are that they are relatively simple, inexpensive, durable, dependable, with low self-discharge rates yet capable of high discharge rates. Disadvantages of SLA or AGM batteries include bulk and weight (very heavy), limited number of full discharge cycles, limited discharge (not deep-cycle), and environmental concerns (hazardous waste).

Lithium-ion polymer (LiPo) technology is relatively new but is perhaps the best performing rechargeable battery as of this writing, and is relatively light weight, making it ideal for radio amateur portable use; very popular today. One manufacturer has ham-specific lithium ion phosphate (LiFePO4) products and even has equipment operating charts to help select an appropriate battery. A bit expensive but worth it to portable operators or those looking for emergency backup power.

One advantage of Nickel-Cadmium (NiCd or NiCad) batteries over other rechargeable types is low internal resistance, meaning you can suck a lot of energy out of them quickly (high-drain), so are popular with the radio control (RC) model crowd, despite their inferiority in other ways (including the “memory effect“).

As mentioned earlier, cells and batteries are not exactly the same thing, even though the term battery is quite often used for individual cells. A battery consists of one or more cells, most always connected in series to reach a desired voltage.

Continue reading →

APRS

AF5NP APRS, Emergency Communications (EmComm), FM (Frequency Modulation), GPS (Global Positioning System), Packet, Position, VHF/UHF

You may have read or heard the term APRS.  This four letter acronym isn’t self-explanatory but is popular and important enough that we should cover the basics.

Do you need APRS? Unlikely.  Do you want it? Maybe.   Planning to buy a new VHF/UHF radio and wonder if this is a feature worth paying for?  Read on.  APRS is a big topic with way more detail than we can present here so we’ll give you a general idea of what it involves along with some research links to answer these questions yourself.

For starters, APRS stands for Automatic Packet Reporting System.

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Some publications mistakenly call it Automatic Position Reporting System

Refer to our packet topic for a background on what packet radio is all about.  What makes APRS a specialized form of packet is what info is transmitted.

APRS supports four data types, including Position/objects, Status, Messages and Queries.  The position packets contain latitude and longitude, a symbol to be displayed on a map, plus optional fields for altitude, course, speed, radiated power, antenna height above average terrain, antenna gain, and voice operating frequency.

While APRS can send packets over greater distances on HF bands, it is more commonly used with VHF FM (2m) radios to share data of interest in the local area such as GPS coordinates, weather, alerts, announcements, and such.

APRS info and messages can be directly between hams but more commonly, packet data is collected by local repeaters (gateways) and sent to the APRS Internet System (APRS-IS) for retrieval anywhere by anybody with a web browser.  Meaning your unlicensed spouse can see where you are located (technically, your transceiver) at any given time.  It is not a one-way system; APRS both transmits and receives packet data.

Also unlike normal packet radio, APRS blindly sends out data addressed to no one in particular (unconnected). Two things to know about this system: 1) no error correction (clean, strong signals required), 2) someone or something must be monitoring to be useful (another APRS ham or internet gateway).

In addition to several good references below, an excellent resource worth reading right now: Intro to APRS (PDF file link), a presentation prepared by John Gorkos AB0OO of the Joplin (MO) ARC.   It discusses what the system is not, significant info you can get through it, what you can do with it (note two separate sections for this), and suggests next steps for getting involved with APRS.

Given all the possibilities above, the primary use of APRS in ham radio is to have a transmitter location reported to a central database periodically so that others can see where a mobile/portable ham is located.

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This makes APRS particularly useful for public service events and emergency communication (EmComm) situations where managers can easily track mobile resources who have messaging capabilities.

There are numerous web services for viewing APRS maps and data but the main one (and simplest) is  aprs.fi .  Click there and you will be taken to a local map showing locations of ham APRS transmitters in your own area.  Looks like this example:

APRS Map

In North America all APRS data is transmitted on 144.390 MHz.

APRSVHFworldmapXx

Just tune your VHF radio to your global frequency to hear the packet squeal, if you are wondering what it sounds like.

APRS requires not only a 2m FM transceiver but also a computer with display and TNC radio-computer interface, plus (normally) a GPS receiver.  Radios with APRS features built in cost more than ordinary mobile or handheld transceivers, mainly because Continue reading →

Selective Calling & Tone Squelch

AF5NP CTCSS, DCS, Emergency Communications (EmComm), FM (Frequency Modulation), PL, Selective Calling, Squelch, Tone

In a previous post we introduced the term squelch and how it was used in basic operation.  As mentioned there modern ham radio work (especially with repeaters) often involves other technologies that fall under a different category named selective calling, tone squelch being the most common form.

Selective calling is different from ordinary carrier or noise squelch.  In practice it is more of a security or channel sharing function.  Selective calling encompasses several similar technologies which largely do the same thing: prevent a transmitted signal from being received by other radios unless a particular code is entered by the sender.

From the Wikipedia article, “Selective calling is akin to the use of a lock on a door. A radio with carrier squelch is unlocked and will let any signal in. Selective calling locks out all signals except ones with the correct “key”, in this case a specific code.”

The most common form of selective calling in use by hams is a tone squelch system with the awkward name of continuous tone-coded squelch system (CTCSS).  Squelch in general is used to keep commercial and amateur radio repeaters from continually transmitting. Since a carrier squelch receiver cannot tell a valid carrier from a spurious signal (noise, etc.), CTCSS is often used as well, as it avoids false key-ups. Use of CTCSS is especially helpful where nearby repeaters may share the same frequency or in a high electrical noise or RF environment.

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As the name implies, CTCSS sends out a continuous tone along with the transmit audio.  The tone is termed, “sub-audible”, although it is often a low audible frequency.  Most radio systems filter out these low frequencies so it is unlikely that you will hear the tone when listening to another ham unless you have an unusual radio and/or are wearing high fidelity headphones.

The CTCSS tone is selected by a repeater operator to avoid duplication with nearby repeaters on the same frequency.  In most cases, the objective is to reduce interference and not restrict legitimate access.  There are 100 established CTCSS frequencies but some are more commonly used than others.

CTCSS is often referred to as PL because it’s easier to say.  They mean the same thing but PL® (stands for Private Line) is a registered trademark of Motorola’s implementation and was the original employment of CTCSS.

 

Besides CTCSS, other forms of selective calling in use by hams include:

  • Selcall (mostly European)
  • Digital-Coded Squelch (DCS)
  • XTCSS

Why it matters to us

T2B04-2018Because various forms of selective calling prevent a signal from being re-transmitted (repeater) or received (simplex) without the proper code or tone, use of CTCSS or DCS is a possible reason other stations cannot receive you.  Especially on a repeater, if others cannot hear you it’s quite likely that you have the wrong code or your tone squelch is turned off.  How to know what the proper setting is?  Consult the repeater directory.

Some Useful Links

CTCSS – RadioReference

How radio “privacy tones” or CTCSS tones work – YouTube video

CTCSS – MDARC

Get the Right Signal Tone – Ham Radio School

Hey, Why Can’t I Access the Repeater? – Ham Radio School

Differences between CTCSS and DCS – Retevis

CTCSS & Tone Burst Ham Radio Repeater Access – electronicsnotes

A Historical and Technical Overview of Tone Squelch Systems – WA6ILQ

Repeater Related Terminology – Repeater Builder group

Squelch

AF5NP Emergency Communications (EmComm), FM (Frequency Modulation), Squelch

Squelch is a funny word that is familiar to many of us without understanding what it really means.  Hard to improve on the definition beyond that in the Technician license exam question:

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Most useful when using voice modes (phone), squelch makes radio operation more bearable by turning off the audio when there is no valid signal.  Without squelch our radios would be cranking out a lot of unwanted background noise.

The reality of both AM and FM radio (which we covered recently) is that there is electrical noise in the bands from many sources, natural and man-made.  This noise is often randomized so that it appears as hiss or fuzz (white noise) from radio receivers.  A squelch circuit mutes receiver audio to block the noise when there is no real signal.  Squelch acts as a noise gate which closes for random noise and opens when a real signal (such as modulated voice) appears on frequency.  How the squelch circuit determines what is a valid signal and what is noise varies; there are a few common techniques (refer to algorithm link in references below).

Squelch is built into more expensive broadcast receivers.  It may also be found on AM transceivers (particularly CB radios) and is a feature of nearly every FM amateur rig.

While less prone to electrical noise, FM technology is susceptible to a lack of true signal.  Traditional FM receivers use an LC tuning circuit that generates ‘hiss’ with no signal present.  You may have noticed this while tuning between stations  on your broadcast FM radio.  Since hams commonly use VHF/UHF FM transceivers for local chat and EmComm work, the squelch feature of our rigs is of particular interest.

Squelch setting is important because if you make it too tight you may not hear a weak signal; too loose and you get constant noise.  General good practice (at least a starting point) is to turn down the squelch until you hear background noise (hiss), then increase the threshold until the noise goes away, then just a little more.

Squelch threshold is always settable on your FM transceiver.  There may be a knob to turn as in the example below, or it may be through keypad menu.

Squelch Adj FT7900

Squelch tail is a common term that is related to all this.  The tail is the brief “pfffft” sound heard when another station stops transmitting.  Audio example on YouTube here.  It is the natural presence of noise during the delay between the time a signal drops and the squelch kicks in.  On a repeater it will often followed by an audible beep or similar courtesy tone.

So far we have discussed the basic squelch feature of common ham radio transceivers. There are other squelch techniques in common use with repeaters such as CTCSS, DCS, and PL.  These fall into a separate category called selective calling or one specific variant known as tone squelch, mainly because they have a different purpose and functionality.  We may discuss this in a future post.

Some Useful Links

Squelch setting – W3ATB blog

Squelch algorithms – PA3FWM site

Squelch Tail – DAP-COM reference

 

Generator Use & Safety

AF5NP CO Carbon Monoxide, Emergency Communications (EmComm), Fire, Generator, Ground, Protection, Safety

Spring is [hopefully] coming soon with expected turbulent weather.  A new hurricane season is also upon us.  Both are liable to cause disruptions to utility electrical power.  Annual ARRL Field Day is also approaching.  Time to think about auxiliary power generators.

Small gasoline-powered generators are relatively common and widely available for emergency or portable electrical power.  It’s a good idea for the prepared homeowner to have one, mainly to keep the fridge/freezer cold during times of sustained power outage.  The savvy radio amateur also recognizes the importance of communications capability in a blackout scenario as well.  Power is needed to make our radios work beyond what limited battery capacity we have, particularly in emergency situations.  Most EmComm groups include generators in their plan and have them on hand.  Not every ham does.

Honda Generator

Consider having a small generator for essential power when the lights are out for hours.  Having a generator is good; knowing how to use it safely is the focus of this topic.  We will look at four related safety considerations:

  1. Carbon Monoxide hazards— CO
  2. Fuel handling and storage (fire)
  3. Generator grounding
  4. Shock hazard

Carbon Monoxide (CO) is the primary hazard with generators, since  CO is produced in the exhaust of all gasoline and natural gas combustion engines. 

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NEVER, ever run a generator inside a dwelling or garage where exhaust can seep into the occupied space.  CO is a colorless and odorless gas which can kill or injure humans and animals.   It can be detected only with chemical or electronic CO detectors; it’s wise to have detectors in every home.

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Always operate a power generator outdoors in a well-ventilated area. Continue reading →

Family Comms Plan

AF5NP Emergency Communications (EmComm), Family, Plan

One of the more useful applications of ham radio (beyond the obvious enjoyment of the hobby) is for emergency communications (EmComm).  In times of man-made or natural disaster, mobile phones and internet may be inoperative or unreliable.  In such times ham radio may be the only way to communicate.

WhenAllElseFails

Extend this idea to your loved ones with a family communications plan.  This would involve you, a spouse and/or children. For it to be practical all would need to be hams with at least a Technician class license.

familyofhams

A family communications plan would be established and written down for all family members to have near their radios.  This would include primary, secondary, and tertiary repeaters in your area.  Also include a simplex frequency and the national call (simplex) frequency in case the repeaters aren’t working or are tied up.

Make sure to test all frequencies between expected locations (home, work, school) with a dry run to discover any interference or lack of coverage.

To help visualize how this might work, let’s say there is a major tornado outbreak that wipes out a large chunk of a mid-sized city one weekday afternoon.  Dad is at work, Mom is at home, and daughter is at school.  Cell phones (voice & text) and internet are not working so none of these people can let each other know where and how they are.  All three members know that the situation is bad so all get on their radios.  Primary and secondary repeaters are busy with dozens of other local hams reporting in damage and trying to reach their families.  Tertiary repeater is open so all three move there.  From his mobile rig Dad reports that he is fine and will make his way home ASAP.  With the base radio Mom reports minor damage with a fence section down.  With her HT Daughter reports that the college is unaffected but has to wait for clearance to leave campus.  All can share updates as needed, and may have to wait their turn on the repeater.

Great idea, but you may have objections.  Let’s address a couple of these:

  1. Getting everybody licensed.  The necessary Tech license is actually pretty easy to obtain.  Five year olds can do it with a little study and coaching.  Not a good excuse.
  2. Cost.  License exam fee is $15 or less.  Many hams already have at least one VHF/UHF FM radio.  Cheap HTs (minimal requirement) can be had for less than $50 each.  Money should not be an excuse.

The licensed family member can train/coach the others to get a license and work on getting more radios.  It may be that they already have multiple radios (base at home, mobile in car, one or two HTs) so all that is needed is establishing the plan and testing it.

Local comms using VHF/UHF is most important in disaster situations but you could extend this beyond line of sight to more regional or national distances using HF equipment.  It gets more complex in this case and practically speaking a General class license would be needed.  Here also non-voice messaging using WinLink may be useful.

An interesting article on a surge in US licensees for EmComm purposes including family members is found here.

Repeater Reverse

AF5NP Emergency Communications (EmComm), Offset, Operation, Repeater, Reverse, Split, Transceiver, VFO

If you aren’t familiar with VHF/UHF repeater operation, now is a good time to review it here.  Repeaters are frequently used for chatting with local hams, regular nets, and EmComm use.

An occasional problem with repeater operation is when a weak transmitter doesn’t have enough power to keep the repeater’s squelch open.  That is, you can tell someone is there but hear little or no signal.  Could be that the transmitter is in a sheltered location, doesn’t have a good antenna, or using too little power.

For whatever reason, they can’t break through with a strong enough signal to be heard.  If you suspect this is happening, you can try listening to them directly instead of through the repeater.  It’s possible that you are closer to the weak transmitter than the repeater is.

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Many hand-held radios (HTs) and mobile VHF/UHF transceivers support this with a repeater reverse function, typically by pushing a button on the radio.

Kenwood Reverse

Recall that a repeater re-transmits what it hears on a different frequency.  The difference in transmit and receive frequencies is called repeater offset and this minimal difference is needed to allow for sharp filtering between them so that the strong transmit signal doesn’t damage sensitive receiver circuitry.

By selecting reverse on a transceiver you then listen to the repeater input frequency instead of its output.  In this manner you can get the weak transmitter’s true signal strength and quality, not what the repeater re-transmits.  This assumes that you are receiving better than the repeater, which is a possibility but not a certainty.

Useful when you want to see if a weak signal Continue reading →

Distress Call

AF5NP Break-Break, Distress, Emergency, Emergency Communications (EmComm), Mayday, SOS

It’s unlikely that you will hear a radio distress call but hams should know how to respond to one.  Hopefully you will never need to send a distress call yourself but it’s best to know how to call for help in an emergency.

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While some situations may be questionable, if life/health/property are genuinely threatened, it merits a distress call.  Basically, if you would want police, fire, or ambulance response, it’s a distress scenario.

Obviously if one is in town with a telephone nearby, the proper response is to call local emergency services (in USA, dial 911).  But if the phones are down or someone is very remote, radio may be the only way to communicate.

Distress calls are formally done by voice mode using the term Mayday-Mayday!  SOS is the CW mode or Morse visual equivalent of Mayday; you are even less likely to encounter it.

If you hear a distress call:

First of all, stop whatever you are doing (QSO, or whatever) and cease all transmissions to avoid interfering with the distress call or a response.

Second (very important!), write down everything you hear related to the distress call.  Under duress, people tend to forget things and stress will be high at both ends of the radio.  Details about the incident are crucial for sending help.  Include the date, time, frequency and mode.

Third, see if anybody else responds. Perhaps there is another station in a better position to react (location, facilities, etc.)  If nobody else does, briefly ID and ask what is the nature of the incident.  The distress station may not have a call sign or know proper radio procedure; be prepared to work with a non-ham at the other end.  If time permits, confirm the details you wrote down with the distress caller.

Fourth, determine how to help the distress station.  You need to get them help, but that depends on the location and nature of the trouble.  If unclear or uncertain, contact local emergency services and let them help you sort it out, even if the distress is far away.  In any case you must relay important detail such as the type of emergency, how many people are involved, and the distressed party’s location.  The Mayday caller may also provide specific guidance if they are trained and knowledgeable.

Lastly, maintain contact with the distress station and emergency responders until help has arrived and the danger is passed.

Know also that in a genuine emergency/distress situation, you can violate normal protocol and rules to assist another station, at least in the USA (probably most other countries as well).  If it requires using a mode, frequency, or power level for which you are not authorized, do it!

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To send a distress call should you ever need to:

If the phones are down, use your VHF/UHF radio on a local repeater or national simplex frequency where other hams are likely  to copy you (choose the most active local repeater).

If you are very remote and there is no chance any line-of-sight radios can pick you up, Continue reading →

Traffic

AF5NP ARRL, Emergency Communications (EmComm), Message, Net (work), Traffic

New hams listening in on a local net are likely to hear the net control station begin the session by asking for stations with traffic.  Seems like there never is traffic, so what’s that all about?

Traffic is ham-speak for passing messages, usually via regular radio nets.

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Messages are almost always formal, written on a form with bureaucratic detail.

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Even friendly, casual messages (“happy birthday, Aunt Edna”) are typically passed this way.

ARRL Radiogram

Such messages (traffic) resemble the old telegram format.  They go back to the very early days of amateur radio when passing messages was a primary function.  In fact, this is from where the US Amateur Radio Relay League (ARRL) derives its name.

Nowadays traffic is mainly an emergency communications (EmComm) function, although the occasional casual message is passed on.  Purpose-specific traffic nets meet regularly to pass messages to stay in practice for when they are really needed, like when there is a local or regional communication outage.  Likewise, local nets support traffic to maintain readiness.

The general traffic flow is from an originating station to a local net where the message is Continue reading →

Clutter

AF5NP Brevity, Clutter, Directed Net, Emergency Communications (EmComm), Etiquette, Facts, factual

New hams, don’t hesitate to make that first radio contact.

Experienced hams, don’t hesitate to try a new band or operating mode.

Technician and General Class hams, don’t hesitate to upgrade your license class.

All hams, don’t hesitate… on the air.  With your mic keyed to transmit, don’t fill up time and space with “um…”, “well…”, “er…”, “aah…” and other such sounds of hesitation.

It’s not only annoying to hear but hesitation really clutters up the airwaves.  In certain cases it impedes more important communication.  For example, during a special event operation or true emergency communication (Emcomm) situation or drill, the Net Control Station (NCS) is constantly talking to various stations.  If you’re using up valuable time on the air, other stations cannot be relaying their info.

A good rule of thumb or general practice is to know exactly what you will say before you key the mic.  Think first, then talk.

If Net Control asks you a question that you cannot immediately answer, don’t take 20 seconds to stall or explain away your delay, just reply that you will get back to them.  This frees up the net for others and lets the NCS know to expect a reply shortly.

The opposite of hesitation in radio work is brevity .  Keep your transmissions short, few, and far between in a special event or Emcomm scenario.

Don’t call in periodically just to let the net know you’re still there.  Net Control and the rest of the net assume you are there unless you have to drop off for a valid reason but you must inform them in such case.

Don’t use 50 words where ten would do. Unfortunately, some hams are long-winded on a special event net.  It takes forethought and practice to keep a report short and simple.   Use the minimum number of words to communicate effectively.

Don’t talk to sound important or just to hear your own voice.  This is heard occasionally on a special event net; others can usually tell when this happens and it’s aggravating.

Study up on Emcomm radio practices, guidelines, procedures and etiquette and then practice these.  Drills and special events are perfect exercise.  Refer to our “EmComm Toolbox” topic for such info.

Another form of clutter to avoid during a special event or Emcomm operation is speculation.  Rumor, guessing, second-hand info, and supposition often lead to confusion and unnecessary concern.  Just the facts, ma’am.  Seriously, only give solid facts.

Log Time

AF5NP Emergency Communications (EmComm), GMT, Log, Time, UTC/UCT, Zulu

Keeping a record of contacts is important in amateur radio.  While no longer required by the FCC in the United States, logging is definitely encouraged.

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For the common, everyday VHF/UHF radio chatter we participate in on a local repeater, contacts are rarely logged.  This is fine, since logging of these would be a tedious nuisance.  Logging of all other contacts is highly recommended.

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Besides frequency, call sign and signal report, date and time of contact are logged.  Time should be when contact begins, not when completed.

In practice, active hams live in two time zones. The first is their local time, which is when they join a net or sign off a contact because dinner is being served.

Local time is what should be recorded in emergency communication (EmComm) logs when participating in drills or actual disaster deployments where local time is more meaningful.

The second zone hams more frequently use for logging is Zulu time, the current time at the Prime Meridian of the World running through Greenwich, England.  Zulu time (Z)  is also known as Greenwich Mean Time (GMT) or Coordinated Universal Time (UTC or sometimes UCT).   If it’s coordinated Universal Time, why is it Called UTC and not CUT?

Standard_World_Time_Zones

Technically GMT is a time zone while UTC is a time standard (details) but practically speaking they are the same thing and in the aviation, military and telecommunications world it’s Zulu time.

Why the name Zulu?  There are 25 integer World Time Zones from -12 through 0 (GMT) to +12. Each one is 15° of Longitude as measured East and West from the Prime Meridian.  These are given alphabetic designations A-Z, less the letter J.  Z (ITU phonetic Zulu) corresponds to the prime meridian at 0° longitude.  Zulu time.

When logging all but EmComm contacts, hams should use Zulu, not their local time.  Then both parties in a logged contact have the same (universal) time and date recorded (date will change at midnight between 2359z and 0000z).  This becomes important when confirming contacts and getting awards.

Going Mobile

AF5NP Amateur Radio, Antenna, Emergency Communications (EmComm), Ham Radio, HT (Handheld Transceiver), Mobile, Transceiver

The Who had a hit tune entitled Going Mobile that may be playing in your head right now.  While the song celebrates the joy of living in a mobile home and traveling caravan-style in the UK, going mobile to hams means using radio equipment in your vehicle.

While some hams have HF radio setups in their cars, mobile predominantly means local VHF/UHF communication.  Besides bring able to talk to our ham buddies while driving around, 2m/70cm capability is particularly useful in case of disaster or other emergency communication (EmComm) situations.  It is perfect for storm spotting and certain public service events.

Mobile operation is popular and important enough that there are a number of US license exam questions involving the topic as you will see below.

Installing and using amateur radio equipment in one’s personal vehicle is too large a topic to cover here so we’ll simply advise you to research details on your own.  Talk to fellow hams and see what/how/why they installed their own gear.

The internet is also a vast resource for [mostly good] info .  One noteworthy site dedicated to mobile ham operation is managed by Alan Applegate, K0BG, and is located here.   It contains exceptionally useful info on most topics presented below.  We encourage you to use this site as a primary reference for your own mobile radio installation and operation.  The ABCs topic is the best place to start.

Before embarking on any of this yourself, there are several important points to consider:

  • Radio type
  • Radio control location
  • Radio mounting
  • Radio power wiring
  • Antenna type and mounting
  • Radio audio/speaker
  • Transmitting while driving
  • Hands-free/Distracted driving laws
  • Noise and interference

We will scratch the surface of each of these topics here:

Radio type-  Choose a mobile radio that best fits your needs, desires, and budget based on several factors:

  • Brand– quality/reliability and/or familiarity/loyalty
  • Transmit power (Watts)
  • Features– Auto power-off, APRS, dual-channel, remote head, cross-band, packet
  • VHF/UHF (V/U) or HF?
  • FM only, or multi-mode?
  • Single-band, dual-band, tri-band, or quad-band?
  • Analog or digital communication, or both?
  • New, reconditioned, or used?

Note that while a hand-held transceiver (HT) can be used in a car, it is significantly limited by its antenna and transmit power.  Both can be improved (linear amplifier and external antenna) but if you really want good mobile performance you should consider a purpose-specific mobile radio.

Radio control location-  Modern mobile transceivers typically feature removable front panels where the operator controls can be positioned in a more convenient, ergonomic, and safe location using a smaller footprint. Continue reading →

Packet Radio

AF5NP Emergency Communications (EmComm), Message, Packet, TNC, Winlink

If you’re exposed to ham radio for any length of time you are sure to hear some discussion of packet radio.

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Without going into much detail, we’ll present a big-picture description here.  Just enough for you to have a basic grasp of what’s involved and give you some idea of how it might apply to you.

Packet radio is a generalized term for a digital communication mode where data is sent in bite-sized chunks (packets) via radio.  The transmission and receipt of packet data is largely automated and features data error correction for reliable messaging.

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Packet radio (sometimes shortened to just packet) blends radio and computer technologies together.  Sounds complicated but it really isn’t.  All you need besides your normal ham radio transceiver is a household computer and an interface between the two.  The heart of this interface is a Terminal Node Controller (TNC) which is an intelligent modem that converts text to audio tones and vice versa.

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Reprinted with permission, 2013 Handbook; copyright ARRL

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Packet radio can be used between hams directly in real-time (peer-to-peer or keyboard-to-keyboard) but is more commonly used to send messages that can be retrieved on demand.  This operates more like email or mobile phone text messaging.

Slow data rates (typically 1200 baud) make large messages impractical, so packet messages should be relatively short and not have any large files attached.  120KB is the max message size accepted by some big message servers.  A 4KB message will transfer in 2-2.5 minutes under ideal conditions at 1200 baud.

Particularly useful for emergency communication (EmComm) messages, packet radio is predominately used on VHF radios (more local) but can be sent over HF bands Continue reading →

Mic Fright and Your First Contact

AF5NP Anxiety, Contact, Elmer, Emergency Communications (EmComm), Experience, First, Listen(ing), Mic (rophone), Practice

Mic fright is a general term for anxiety leading to freezing, choking or hesitating when speaking into a microphone (mic).  The physiological response of worrying about saying the right thing to an audience large or small is very natural and expected.

micfright

Mic fright or shyness is a reality in public speaking, stage performance and similar situations.  Of course, it’s an important topic to new amateur radio operators so let’s provide some perspective and encouragement here.

Making that first voice contact over the radio can be an anxious moment for many new hams.  This can also carry over into the first several radio contacts where you worry about saying the right thing and following the rules.

First off, don’t let the “rules” make you nervous.  It mainly comes down to proper identification which means giving your call sign every 10 minutes during an exchange and at the end of your last transmission (USA rules, other countries vary).  That’s pretty easy to remember.

Second, every ham was a newbie once and remembers what it was like not knowing exactly what they were doing.  Most will be patient and helpful, giving coaching and gentle reminders along the way as needed.

For general phone (voice) contacts, there are no real procedures and formalities to worry about; it’s more conversational, much like a phone call.  While radio amateurs often use jargon, abbreviation and technical terms (see our Ham-Speak topic), this is not mandatory.  Hopefully that takes some of the pressure off to make you more relaxed for your first few contacts.

A starting point for getting on the air the first time is to listen in on the local (VHF/UHF) repeaters and HF SSB bands for a few hours to learn what people say and how they say it.  If you follow these examples you are almost certain to be successful when transmitting on your radio.

An excellent way to get past mic fright and performance anxiety is to ease into it with Continue reading →

Public Service Events

AF5NP Emergency Communications (EmComm), HT (Handheld Transceiver), Public Service, QST

Are you a new ham who wants to practice radio communication?

Just getting started in amateur radio and want to learn about emergency communications (EmComm)?

Are you a ham who wants to make better use of your hobby?

If you answered yes to any of these, consider helping with a local public service event (PSE). Public Service Events provide an excellent chance to practice your EmComm radio skills.  Not only is it fun and interesting, but you will gain valuable experience in radio communications similar to a real disaster scenario, without the stress and urgency of a life and death situation.

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Ham radio operators are often invited to assist with PSEs to provide primary or supplementary communication.  PSEs typically involve parades, races or large gatherings.  They normally use VHF/UHF radios so you don’t need any fancy equipment or big antennas.

Participants may be stationary  or mobile, depending on the nature of the event.  You may be sitting or standing or walking around.

Because hams supporting a PSE will often use a handheld transceiver (HT) it’s a good idea to have a few recommended HT accessories.  First would be a quality 1/4-wave antenna in place of the poorly-performing factory “rubber duck”.  Second is a spare battery pack for your radio.  Third would be headphone(s).

A must-read for new hams is Continue reading →

Powerpole® Connectors

AF5NP DC Power, Emergency Communications (EmComm), Power Supply, Powerpole®

The Anderson Power Products Company makes a family of electrical connectors with the registered trademark name of Powerpole®.  Now that we have established that, we’ll skip the ® symbol from now on.

Powerpole connectors come in several sizes and colors.  Housing size depends on current rating, from 15A  up to monstrous 350A and supporting wire sizes from 20AWG wire up to heavy 3/0 cable using different connector contacts.

powerpole-family

Hams in the US, and particularly within EmComm groups such as ARES, have adopted the 15-45A  Powerpole product as the de facto standard for 12VDC  power interconnect for amateur radio equipment.  These connectors are gaining popularity world-wide as well, so you will see more and more usage of this flavor of Powerpole connector being used everywhere.

powerpoles

Besides the convenience of a high-current quick-connect, having a standard means one ham’s equipment can be plugged into another’s  power source.  This is particularly important in emergency communication situations.  Additionally, a standard drives greater availability of commercial products that support it.

One reason Powerpole connectors are growing in popularity is that they have some unique advantages over other electrical connectors: Continue reading →

EmComm Toolbox

AF5NP ARES, ARRL, Directed Net, Emergency Communications (EmComm), Etiquette, FCC, Ham-Speak, Language, Training

Many new hams get involved in emergency communications (EmComm) and it may even be their primary focus or purpose for getting an amateur radio license.  Emergency communications is the first of five basic principles spelled out by the FCC for the existence of the licensed amateur radio service in Part 97:

Section 97.1(a): Recognition and enhancement of the value of the amateur service to the public as a voluntary noncommercial communication service, particularly with respect to providing emergency communications.

In fact, by accepting an FCC operator/primary station license grant under these rules, USA amateurs are obliged to provide emergency communications as needed.  Not that you’ll get thrown in the slammer if you don’t help, but all licensed hams with the equipment and experience should help out in case of disaster or other EmComm situation, and most do so.

Having said all that, I would encourage all hams to join a local or regional EmComm group (such as ARES or RACES in the USA) and train and drill with them to get some experience.  It’s not enough to know how to talk on a repeater or social net; things get more serious in an EmComm situation.

There are more formal radio operating practices and language used in EmComm which is almost always conducted as a directed net.  You need to learn when and how to communicate and with whom and what to say and why things are done a certain way.  Participating in EmComm drills and public service events is important training, as is listening in on EmComm training nets. Taking EmComm courses such as the ARRL’s Introduction to Emergency Communication Course EC-001 is also of great benefit.

To familiarize you with the Who/What/When/Where/Why/How of EmComm, attached here Continue reading →

Know Your Radio

AF5NP Configuration, Emergency Communications (EmComm), HT (Handheld Transceiver), Mobile, Radio, Settings

Do you know how to change the settings on all of your radios?  You should, particularly with the VHF/UHF rigs that would be used in an emergency situation in case of a local disaster.

It may seem silly to ask this question when such knowledge is often assumed.  But consider these factors:

  • Many of the modern radios can be configured via software on a PC, often including memory channels for local repeaters.  Did you actually set up your radio manually, or was it cloned or computer configured?
  • Many hams have multiple transceivers- handhelds (HTs), mobile, and base station rigs.  Configuration of these is likely different for each model, even with the same manufacturer.
  • Hams may have different makes of the same type of radio as well, each with very different configuration procedures.  If you have both Yaesu and  Baofeng HTs, the procedures will be quite different.

Consequently some hams only know how to turn the radio on and off, adjust the volume and squelch, and then select a memory channel to work a local repeater.  This is OK when you want to chat with a buddy, since little can go wrong and there are no real consequences.

But during a drill, public service event or EmComm deployment, we have to be flexible and prepared to change things up.  There are many reasons things don’t go as planned, and you may have to change a setting on your radio.  Even something as simple as communicating outside the local area will require different repeater access tones.  Some events use a portable repeater that you may not have programmed into your radio.  Many of us have been embarrassed in the field when Continue reading →

Directed Net

AF5NP ARES, Directed Net, Double, Emergency Communications (EmComm), Net (work)

An amateur radio net (ham-speak for network) is an organized gathering of at least three hams on the air for a specific purpose.  It is usually on a regular schedule (e.g., 9pm local on Wednesdays) and specific frequency (e.g., 146.900 repeater).  Nets are organized for various reasons, usually conforming to one of two categories: hobby/pleasure and utilitarian.  Nets may be impromptu and unscheduled, such as during severe weather when a net may be quickly organized, or following a local emergency or disaster.

While there are CW (Morse code) and voice (phone) nets on the HF bands, most ham nets are found on VHF/UHF repeaters to serve area organizations such as a club or emergency communication group. EmComm organizations such as ARES typically have weekly training nets so it’s likely that one is in your area.

Radio nets can be formal or informal.  You are most likely to encounter formal nets which have a more structured feel.

When joining a more formal net, you are likely to hear the phrase, “directed net.”  This means that one operator is in charge of the net, and this person is Continue reading →

Disable Yaesu WIRES Feature

AF5NP DTMF, Echolink, Emergency Communications (EmComm), IRLP, Transceiver, VoIP, WIRES, Yaesu

Yaesu makes some of the best and most popular transceivers for amateur radio use.  In some locations, Yaesus are the majority of radios working local VHF/UHF repeaters.

One of the few criticisms of Yaesu is the WIRES™ feature.  WIRES is an acronym for Wide-coverage Internet Repeater Enhancement System and is unique to this brand of transceiver.  The system can link compatible repeaters together via Voice over Internet Protocol (VoIP).  WIRES-equipped radios using these linked repeaters can communicate over great distances since they use the internet as a pathway.  It’s a hybrid communication scheme combining short-distance radio and long-distance internet.

This sounds like a good idea but is popular only on Yaesu’s home turf in Japan.  While some can be found outside of Japan, WIRES™-compatible repeaters are not common in the rest of the world.   The Internet Repeater Linking Project (IRLP) and Echolink are similar systems more widely adopted and prolific.

So what’s the problem with WIRES™?  It uses a dual-tone multi-frequency (DTMF) signal to identify a Yaesu transceiver to a WIRES-compatible repeater.  Unfortunately, when a non-compatible repeater see DTMF signals it Continue reading →

When All Else Fails…

AF5NP ARES, Emergency Communications (EmComm)

Whatever your interest and motivation for getting into ham radio, the hobby has one undeniable benefit when things go terribly wrong in the local community: it may be the only means of communication in case of natural or man-made disaster when commercial radio, television, and phone systems are down.

Even if landline and mobile phones are functional, government and disaster response agencies have priority to use these channels of communication, which means personal calls are unlikely to get through.  The internet may also be disabled or compromised.  In this situation where personal communication is difficult at best, ham radio is the only practical means of getting messages across town and even farther.

Unfortunately this scenario is real too many times and has led to the emergency communications (EmComm) slogan, “When All Else Fails…Amateur Radio.”

WhenAllElseFails

Hams have a reputation for getting radios and antennas set up quickly without commercial power and organizing EmComm networks for Continue reading →

Phonetics

AF5NP Alphabet, Emergency Communications (EmComm), Net (work), Phonetics

One of the first things a new ham needs to learn when they get on the air is the phonetic alphabet.  Because many alphabet letters sound similar over the air (especially in poor conditions), it is helpful to use phonetics when spelling out words or giving your call sign accurately.  This is particularly important in emergency communications (EmComm) and when checking into a radio net, which is where many new hams get started.

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A good phonetic alphabet is clear, differentiated, and commonly understood, unlike this joke phonetic chart:

Phonetics 2

These days,  amateur radio protocol favors the International Telecommunication Union (ITU) phonetic alphabet, also used in international aviation and the NATO military, making it fairly universal.  You are likely to hear other phonetic alphabets on the air but should know the ITU version and use it.  Start learning even before you take your license exam so you are ready to go when you get your ticket.

The best way to learn ITU phonetics is to practice.  Familiarize yourself with the phonetics and then practice by spelling words out.  A great way to do this is while sitting idle at a traffic light or while walking through a parking lot.  Just start spelling out signs and license plates phonetically.  When you see a stop sign, just say out loud, “Sierra Tango Oscar Papa.”

Note that there are official pronunciations for each character and a few may seem a little odd; this is to accommodate many native languages, not just American English.  There are also specific ways of pronouncing certain numbers (niner is the most obvious one) and punctuation.  Be advised that the official ITU number pronunciation is very odd (a mixture of languages) and the ones shown below are more common for amateur radio usage.

One good ITU phonetic alphabet link is pasted below.

Character

A

 Phonetic

Alfa

 Pronunciation

ALFAH
B Bravo BRAHVOH
C Charlie CHARLEE
D Delta DELLTAH
E Echo ECKOH
F Foxtrot FOKSTROT
G Golf GOLF
H Hotel HOHTELL
I India INDEE AH
J Juliett JEWLEE ETT
K Kilo KEYLOH
L Lima LEEMAH
M Mike MIKE
N November NOVEMBER
O Oscar OSSCAH
P Papa PAHPAH
Q Quebec KEHBECK
R Romeo ROWME OH
S Sierra SEEAIRAH
T Tango TANGGO
U Uniform YOUNEE FORM
V Victor VIKTAH
W Whiskey WISSKEY
X X-ray ECKSRAY
Y Yankee YANGKEY
Z Zulu ZOOLOO
0 Zero ZEE-RO
1 One WUN
2 Two TOO
3 Three TREE
4 Four FOW-ER
5 Five FIFE
6 Six SIX
7 Seven SEV-EN
8 Eight AIT
9 Nine NIN-ER

The official ITU chart is found here >>  ITU phonetic chart

For a tad more fun we present a pictorial-enhanced ITU phonetics chart, author unknown: