Beginner’s Corner July 2015

Give Your Radio’s Signal Some Air Part 1

 

Most new hams will buy a small handheld portable radio as their first radio.  This type of radio is better known as a Handy Talkie or HT. When a new ham gets that radio programmed, he or she will hopefully try to make contacts.   Living in Gwinnett County, the GARS repeaters are a likely target for that first QSO (contact).   Some new hams are ambitious and will program every repeater in the Metro Atlanta area.  They will get on a distant repeater frequency, key up their HT, and become discouraged when nothing happens.  It’s not your fault, nor your radio’s fault.  It could be that that the signal from your antenna just isn’t getting very far.

Virtually HTs come with a stock antenna, called a “rubber duckie” by many.  The problem with these stock antennas is they are horribly inefficient.  I read somewhere that they actually lose almost half of the power that the HT puts out.  On high power, most HTs put out 5 watts.  After going through the rubber duckie, only 3 watts normally gets out.  Solution?  First replace that stock antenna with a better one, called a “whip”.  Several companies make really good whip antennas.  They are available at our local ham radio store or on the Internet.

If you try using your HT in a vehicle, using a stock antenna isn’t good either.  You can get a magnetic mount antenna that mounts on the top of your metal vehicle roof.  You can run the antenna cable through one of the vehicle doors.  Just open the door, run the end of the cable into the vehicle and shut the door.  Once the antenna cable is in the vehicle, connect it to your HT.  The plug on your new magnetic mount antenna is called a PL-259 plug.  Most HTs have what is called an “SMA” plug.  The two are not compatible, and you will need to pick up a “SO-239 to SMA” adapter to hook between the antenna cable and your HT.  Going to the ham radio store to pick up a magnetic mount antenna? Bring along your HT with you and the salesperson will help you get the right adapter. 

It is best to get a dual-band antenna for your vehicle, even if your HT works only on a single band.  Most hams will eventually own more than one rig, and your next rig might just be a dual band (VHF/UHF) one.  Just as radios need to be tuned, antennas usually need to be tuned, as well.  You learned about standing wave ratio (SWR) before you took your technician test.  If you know of a ham who can check your antenna for you, he or she should be able to tune your antenna for maximum performance.  However, in my experience, it is not critical.

We will discuss more about giving your radio’s signal some air in future columns.

73,

David Harden, KJ4CMY