[ARDF] Protractors

[Jay Hennigan]

On Mon, 25 Oct 2004, Kenneth E. Harker wrote:

>      For those who use protractors to plot bearings on a map while in
> the woods, what kind of protractor do you use?  The standard elementary
> school variety (if so, how do you use it?) or something more complex like
> these:
>
>      http://www.celestaire.com/catalog/products/4402.html
>      http://www.celestaire.com/catalog/products/4407.html
>
>      For those who don't use protractors, how do you plot bearings?

Practice drawing lines by estimation.  A protractor is just one more item
to carry with you that you have to keep loose and accessible.

* Map

* Compass

* Receiver/antenna

* Writing implement(s) [taped to headphone lead or on lanyard]

(plus stopwatch and E-punch stick that are secured to wrist and finger)

are plenty to keep track of, for me.

I have attached the compass to the antenna/receiver so that's one less
item.  I use only one color (red as it stands out and doesn't look like
a trail or road), and put hash marks along the bearing line to indicate
which transmitter, I II III IV V.

Bob Frey has made clear pre-printed stickers with a compass rose, exactly
the size of the 750M exclusion zone that he puts over the start triangle
which serve both to show the exclusion zone and to give you a guide for
estimating bearings.  If you use a map board they work well but often the
start is at the edge of the map which means that part of the circle won't
show (or you need an overzize map board).  If you fold the map these won't
be as useful.

You should certainly be able to freehand draw a line within 20 degrees
of what you can with a protractor within five seconds or less.  With some
practice 10 degrees.  This is likely to better than the resolution of
your antenna on 144 anyway.  If you use a protractor you would also
presumably use a straightedge, another item to carry and more time taken
to draw the line.  On 3.5 a protractor and straightedge might help to
get a slightly more precise bearing than what can be drawn freehand but
even from across the map I don't think it would help that much in terms
of locating you that much closer to the Tx.

--
Jay Hennigan - CCIE #7880 - Network Administration - jay at west.net
WestNet:  Connecting you to the planet.  805 884-6323      WB6RDV
NetLojix Communications, Inc.  -  http://www.netlojix.com/