In article ,
Ian White G/GM3SEK wrote:
A simple way to de-sensitize a handheld rig for close-in RDF purposes is
to lower the whole rig (antenna and all) into a metal pipe, on the end
of a piece of string. The further you lower the rig inside the pipe, the
less sensitive it becomes. It may look crude, but this is Reg's piston
attenuator in action!
Yup. Pringles cans are often used for this. I made a nice
heavier-duty version by recycling the lower half of a water-filter
cartridge - light aluminum, easily hacksawed to the desired length.
This system has no directional properties, but at short range you can
often "DF" on signal strength alone.
You can arrange some amount of crude directionality by holding the
attenuator-tube-with-HT-in-it in front of your torso, right next to
your chest, and then spinning around in place. This "body fade"
technique can give you a reasonably directional null when you're
facing away from the signal source. If the null isn't sharp enough,
lower the HT further into the tube to increase the attenuation, and
try again.
--
Dave Platt AE6EO
Hosting the Jade Warrior home page:
http://www.radagast.org/jade-warrior
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