by David Slatter G0CJG
This page shows details of a development by Dave G0CJG based on using a low cost receiver (i.e. Baofeng UV5R), a DF antenna and a solar powered TDOA (Time Difference of Arrival) device for 70cms. This project was built by many club members and successfully used for club DF hunts.
There is an App for iPhone which can assist with recording information during DF Hunts – http://foxhunt.rail.com/foxhunt/Home.html or you should get hold of a local OS map
Dave demonstrated as part of his talk how the device out performs other previous equipment he has developed when you are in close proximity to the “fox” as well as more remote stations. This is a low cost project costing <£10 and based around a £1 solar garden light!
The construction details can be downloaded from the bottom of this page.
The following image shows a breakdown of the components used to build the device.
The rear side of the completed board.
The mounted board along with direction indicator fixed to the case of the solar light
The finished item as Dave said not the most elegant but functional & works !