G0CJG – Solar DF for 70cms

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.

G0CJG Demonstrating Solar DF
G0CJG Demonstrating Solar DF

The following image shows a breakdown of the components used to build the device.

Solar DF Components
Solar DF Components

The rear side of the completed board.

Solar DF Board Rear
Solar DF Board Rear

The mounted board along with direction indicator fixed to the case of the solar light

Completed Basic Build
Completed Basic Build

The finished item as Dave said not the most elegant but functional & works !

Prototype Solar DF Unit
Prototype Solar DF Unit