We’ve seen [Todd Harrison]’s work a few times before, but he’s never involved his son so throughly before. This past Easter, he thought it would be a good idea for his son and a few of his friends to take part in an easter egg hunt. Being the ham he is, he decided to turn an easter egg hunt into an adventure in radio direction finding, or as amateur radio operators call it, a fox hunt.
[Todd] put together a great tutorial on building a yagi – a simple directional antenna – out of a couple of pieces of PVC pipe and a few aluminum and brass rods. With this and a handheld ham set, [Todd] hid a fox along with a stuffed easter bunny and a basket of candy near a local park. Operating under the guidance of his dad, [Todd]’s son and his friends were eventually able to find the fox. Leaving candy out in the Arizona sun probably wasn’t [Todd]’s best idea – the fox, and candy, were covered in ants when they were found – but it was a great introduction to amateur radio.
Two decades ago I was part of an Explorer troop that built our own RDF antennas similar to this one, all the way from bare copper clad to assembling the masts. Our foxhunts involved a person behind the transmitter, so it was a little more like hide-and-go-seek over a many-acre industrial park (the multipath from the buildings added to the fun). It was by far the most popular event save for the one SAREX voice contact schedule we had.
IMNSHO it’d be safer to use a flexible tape measure based Yagi, as the kids may get excited & someone otherwise may get spiked with rigid elements etc. In tight spaces higher freq.70cm (~433 MHz) makes for more compact antenna as well – see my Instructable =>http://www.instructables.com/id/433-MHz-tape-measure-antenna-suits-UHF-transmitte/ Stan. ZL2APS ( since 1967)
If you’re receiving only (you are, here) you don’t even need to bother with using proper antenna dimensions anyway – you’ll lose some of the signal strength yes, but not enough to really matter when you’re looking for the void anyway.
these kids are looking like having a lot of fun ;)
just kidding, here in germany it started to snow again this easter :)