5. Networking Using Simplex

Now we come to the real heart of personal safety radio.  Two-meter communications are frequently via repeaters, and repeaters offer amazing gains in coverage.  For exactly that reason, though, they can become congested.  Long conversations are unwelcome, because they block out other potential users.  More important for our purposes, though, the repeaters may not continue functioning during an emergency, since they are remote and unattended.  Also, there are still areas where repeaters are not available, particularly in remote parts of the country.

Repeaters have a segment of the amateur 2-meter band reserved for their pairs of channels (receiving and re-transmitting).  These reservations are not by law, but by common agreement by a majority of the license-holders.  However, the same agreement has reserved over 20 channels for simplex communications –  meaning direct from radio to radio, with no repeater involved.  Communications on these channels are open to any license holder, any time.  Since the signals are direct, there is no reliance on equipment outside your control: all you need is your own functioning HT and anyone else who also has one.  True independence!  Best of all, because repeaters are so popular, the simplex channels (at least in our area) are almost always unused – despite being always available.

You may recall that a HT has a typical range of perhaps 5 to 10 miles, depending on whether or not there are massive obstacles blocking the signal.  This can be extended up to 30 or more miles with an elevated external antenna, or a more powerful (typically vehicle-mounted) transmitter.  But whatever the range from your position with your HT, as long as you can reach one listener, your message can be relayed onward.

Can you expect to reach at least one listener?  You may be surprised.  A recent count confirmed that in Napa County alone, there are 500 current license-holders.  Most of them are not active in radio clubs or similar organizations, but the vast majority of them will have at least a 2-meter HT – because that is the quickest and least expensive way to get on the air as soon as they received their license.  If they had a reason to charge up and switch on those radios, they would provide coverage all over the County.  The goal of this series of articles is to prompt more of them to do just that, in conjunction with all those of you becoming interested in the safety aspects the radios offer.  And while I may use Napa County as my example, the SCOOPR principles are equally valid anywhere.

So the missing link not yet discussed is exactly that – a need to set up links.  You need to find out how far your HT can transmit a usable signal (receiving is usually not the problem, as the receiver part of your HT is very sensitive).  In fact, you want to determine how many linkups you can make within that range.  These contacts will all be ones who can contact you when they need to, as well.  With that neighborhood “phone directory” established, you have your personal safety radio – just leave your HT on all the time, with a charger keeping its battery full continuously, and you will always be connected.

To find those links, as many HT’s as possible need to be on the air at the same time.  Once this has been done in a few sessions, no further organizational tasks are needed at all.  Dates and times for these “radio range events” need to be publicized in advance, and then a half hour or so of conversations will provide everyone with all the data they need to know.  In the next article, a way to set up County-wide coverage will be explained in detail.

Previous Page          Next Page