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Fox Hunting 101 - Part 3
#1
Cross Polarization

The key factor in fox hunting is reducing the received strength of the signal from the hidden transmitter in order to enhance the ability to find a directional null. Strong signals seem to come from every direction but when the signal is weak it is easier to hear a stronger signal coming from one direction. Dave, VE3WI, has already suggested using the body shielding technique which is a very valid and effective way to achieve signal attenuation. By holding our HT close to our body we can shield signals coming from every direction except straight ahead.

There is another technique we can also use, perhaps in combination with body shielding, to reduce received signal strength. In our Basic licensing courses we learned about cross-polarization. If the transmitting antenna is vertically polarized, a horizontally polarized receiving antenna will pickup a significantly reduced signal. In theory cross-polarization loss is infinite but, in practice, reflected signals from multiple angles are also picked up. So if the transmitting antenna is vertical, holding our HT antenna horizontally will reduce a weak signal a little more.


Why don't we get a group of GBARC members together to do some local fox-hunting. Experienced fox-hunters can help train newcomers in the techniques used. A typical event lasts a couple of hours and ends when a hunter successfully tracks down a hidden low power transmitter. Please reply to this post if you would like to know more, or get involved.
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#2
Yes, count me in
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