Doug, VE7XAT

CQ Worldwide FOXHUNT weekend
Saturday, May 12, 2012
Silverdale, WA

Last revised: May 23, 2012

Doug, VE7XAT


We had beautiful weather with a total of nine participants from Tacoma, Kitsap, Seattle and Port Angeles.  Silverdale is a new hunt area  and was selected for its central location. The base for fox #1 (Tx #1) was at the South end of Clear Creek drainage as it enters Dyes inlet; 47° 39.067'N, 122° 41.087'W.  Clear creek extends over 5 miles with many scenic trails in a close-in urban setting.  It turns out to be a nice on-foot bunny hunt area with many access points.

To reach this location the exercise was set up in two parts; vehicle then on-foot.  You had to find Tx #1 by vehicle first to establish the starting point for Tx #2 and #3.  All the participants had trouble finding the first Tx.  It took nearly two hours for the fastest.  Most have experience with on-foot hunts so using vehicles is new.  I should also mention that the starting location for the auto hunt was undefined, you could start from anywhere within the map boundary.  Rich, KR7W pointed out that Tx #1 was very weak.  It turned out, the antenna, which was a mag mount on the top of my vehicle had a broken connection with high VSWR.  This reduced the available signal and probably contributed to the difficulties.

All in all everyone seemed satisfied and motivated to plan future hunts.  Follows the prep that went into this one:

Pre-event Planning:

This will be a little different, combining a vehicle hunt with the plain old "on-foot" variety.  It will be in two parts.  I also wanted to change the hunt site to something  central for most participants.

RDF (radio Direction Finding) is often used to locate RF interference which requires localization before you start using hand held equipment.    The first part requires a vehicle but because of the hazards using a vehicle while trying to obtain bearings, we'll have no time recording and the start location will be from wherever you think is a good spot.  Speed on this leg will not be important.  You'll be searching for Tx #1 only.  Once everyone reaches Tx#1,  we'll start together for the second part which will be "on-foot" for Tx #2 and #3.

The first leg will encourage triangulation more than "on-foot" hunts.  Gas is expensive so you can team up if their are enough participants with vehicles.  Of course, do you trust them with the info they pass on or will they try to send you off on a "wild goose chase"?  Note that antenna polarization for Tx #1 will be vertical so Doppler systems would work.  But, antennas mounted on a vehicle are not really required.  The recommended procedure is to drive to a safe location, park and obtain a bearing  by getting out of the vehicle with your regular on-foot equipment.  Then plot the results on a map.  After you take about three bearings from different locations, you'll begin to zero in on TX #1 location.  You're responsible for your own maps and the internet has many options.

All that's needed is your regular gear.  Sounds simple, right?  We'll see?  Never never attempt to take bearings while underway; very dangerous indeed!

Tx #1 will be in a vehicle at a parking lot and this will become the "start" location for the rest of the hunt (part 2).  Transmitters #2 and #3 will be turned on by remote control around 1200 noon.    Everything  is "on-foot" from this point on.

At 1500 we may choose to meet at one of the many food/drink facilities in Silverdale if participants are up to it?

General Information:

Map of Hunt area:

Transmitters will be located somewhere within the bounds of this map.  Tx #1 signal should be within range for most of this area.  Your selection of your initial starting point needs to take this into consideration.   Tx #1 will remain operational till 1500 and act as a homing signal back to the start for the "on-foot" portion.