Using Your Radio

A few more things about your HT need to be clarified.

Those radios have a limited range, even at home.  Depending on your location, you might be able to contact another ham radio a few miles away.  That sort of contact is called “simplex”, and the name is probably self-explanatory: you agree on a frequency, and you take turns talking to each other on it. 

Yes, you take turns.  That’s important.  Put two signals on the same frequency at the same time, and nothing is understandable.  You don’t hear a little of both, as you might on some telephones; you hear nothing of any use.  Simplex communication is one way at a time. 

You are using your HT set so you can be mobile, and maybe your contact is too.  What that means, though, is that sooner or later you will not be within range of each other, and the communication will be completely cut off. 

That is why simplex is not the usual mode of interest to us, at least not now.  Fortunately, hams recognized the problem long ago, and have to a large extent solved it by establishing repeaters.

Repeaters are automated radio stations that are situated as high as possible, to get a good view of a large area.  Remember, radio signals on the frequencies our HT’s use are a lot like light – they travel on the line of sight.  Put a receiver high up, and a lot more signals will be visible, including yours.  Then, make that receiver pipe what it receives into a nearby transmitter.  Now your copied and amplified signal is coming from a high point, visible to many more receivers on the ground, including the contact who had moved out of range of your simplex signal.  You can resume your conversation.  It’s simplex between you and the repeater, and simplex between the repeater and your contact, but it’s just called using a repeater. 

Some hams and clubs put up and maintain repeaters, and often allow anyone to use them without registration or fee.  That’s an example of the fellowship of the amateur radio world in action. 

But remember, it’s one at a time on any given frequency.  That is part of the code of manners most hams follow.  You must not hog the space for more than a few minutes with idle chatter. (However, when you are using ARRUMBA, you have an urgent message, and all other repeater users are going to make way for you, once you make this understood.)  Repeaters make wide-area messaging with our tiny HT’s possible. 

In urban areas, there may be many repeaters available.  To avoid congestion from repeating signals coming from a different repeater group, many repeaters use a CTCSS, or “PL”, code.  This is a short audio code on a frequency that your HT will broadcast with its signals. With the right code, your repeater pushes your signal onward, ignoring other signals with different codes; and your receiver ignores signals without that same code (while at the same time removing it from what you hear).  That is why you have to make sure the HT you buy is CTCSS-capable.

Another point to keep in mind: your cellphone conversations are private.  But with your HT, it’s just like regular broadcast radio, and nothing is private.  Anyone listening on your frequency with a capable receiver can hear what you say.  That doesn’t matter to you, though, if you are making use of ARRUMBA — the more listeners the better, because you need help. 

By the way, some folks just listen, using a scanner for the pure interest of it all and without any way to call you back.  But, once they understand your predicament, they are still in a position to start helping you with a phone call for help.  And that’s your goal.

Oh, and one more thing.  You can’t use your radio without a license.  For good reason.  More next time.

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