Mobile

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 →

Stuck Microphone

AF5NP Directed Net, HT (Handheld Transceiver), Mic (rophone), Mobile, Net (work), PTT (push to talk), Repeater

While it’s mainly a local VHF/UHF communications issue, stuck microphones can be a real problem.

A stuck mic situation is when a radio operator inadvertently transmits for an extended time because they have unintentionally triggered the push to talk or transmit switch on their radio.  Consequences of a stuck mic range from being a nuisance to a life-threatening disruption. At best a stuck mic ties up a repeater or simplex frequency with dead air or noise.  At worst it blocks urgent communication during a disaster net or public service event.

One common stuck mic situation involves a mobile unit with the hand-held mic loose in the vehicle where it might get wedged into the seat to trigger the PTT button.  Best practice here is to keep the mic clipped into a hanger when not being used to minimize inadvertent transmission.

mobilemicclipped
Keeping a mobile mic secure in clip minimizes chance of inadvertent keying.

Another common situation involves mic accessories with HTs during a public service event or emergency deployment.  When using a speaker-mic or headset, ensure that the PTT button is protected from accidental triggering.  Also, the Yaesu FT-60 is a wonderful handheld radio and many hams have them, but they (and others like them) have a squirrely speaker/mic jack that is prone to false triggers when the connector is not seated completely.  So make sure your accessory is connected securely and not prone to pulling out when the radio is clipped to your belt or in a pocket or something like that.

yaesu-spkr-mic
External mic or headset prone to false PTT triggers because of plug design on certain HTs.

In any case, awareness is our first line of defense.  Be aware that a stuck mic is a problem and that you might be the culprit.

stuckmicmeme
Don’t be this guy!

Keep an eye on your transmit light to make sure it’s not on when 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 →

DC Power Supply Ratings

AF5NP DC Power, Electromagnetic Interference (EMI), Linear, Mobile, Power Supply, Ratings/Specifications, Regulator/Regulated, SMPS

Except for handheld transceivers (HTs), most modern ham radio gear uses 12V DC power.  You may find vintage radios and more recent designs that require AC main power, but the VHF/UHF mobile radios and the latest HF transceivers run off of 12-13.5VDC.   Nearly all of the modern all-band transceivers use 12VDC power as well so that they can be operated mobile or portable.

T5A06

If you want to install a mobile radio in your home instead of your vehicle (an excellent idea, by the way, if you don’t have an all-band rig) you will need a DC power supply for it.  Same goes for the latest HF transceivers; they require 12VDC power but don’t often include the power supply.  Additionally, many radio accessories require 12V nominal power.

Astron RS-35M 35 Amp DC Power Supply with Meters 120V AC in / 13.8 Volts DC Out     MFJ 4230MVP 30 AMP Switching Power Supply With Meter, 4-16 Volts & Power Poles    NEW Pyramid PS8KX AC to DC 8 Amp 12V Fully Regulated Low Ripple Power Supply     NEW QJE PS50SWIII 50 Amp Switching Power Supply with Volt/Amp Meter     JETSTREAM JTPS30LCD - 9 ~ 12 Volt 30 AMP Max Switching Power Supply w/ LCD Meter

Examples of ham gear DC power supplies.

The 50W mobile radios and 100W transceivers need a lot of current at 12V to operate at full output power.  Sizing a DC power supply for these plus accessories isn’t quite as straightforward as it would seem.

For one, you cannot simply take radio output power and divide by 12V to get amperes. Continue reading →

Understanding Antennas-A Simplified Perspective

AF5NP Antenna, Bandwidth, Counterpoise, Delta, Dipole, Directivity, Efficiency, Gain, Ground Plane, HT (Handheld Transceiver), Impedance, J-Pole, Loop, Magnetic Mount (Mag Mount), Mobile, Monopole, Polarization, Quad, Rat Tail, Resonant, Rubber Duck, Standing Waves, SWR (Standing Wave Ratio), Transmission Line, Wavelength, Yagi

A PowerPoint slideshow, Understanding Antennas / A Simplified Perspective for Ham Radio Operators is downloadable here:  Understanding Antennas-A Simplified Perspective

This presentation provides a working understanding of amateur radio antennas without being overly technical or dry.

The target audience is newer hams with limited knowledge of antennas.  It is presented at the Technician license level. You will see Continue reading →