Metal detecting is widely used as a hobby searching for buried historic treasure, and by the military searching for mines and shells.
Usually the detectorist would be wearing headphones connected to the audio output of the control box.
He would put the detector on the ground while digging a hole at the point where the signal is loudest.
Time and time again the cord to the phones gets tugged and falls off. Sometimes detectorists dig through the headphone cable.
One of us at HIC took up detecting and found this problem all too frustrating so we set out to solve it.
We produced a matchbox-sized radio transmitter which could plug into the detector's audio socket or be fixed to the detector shaft by Velcro patches.
Then with radio headphones operating at 863MHz there was no longer need for the troublesome long cable.
The radio adaptor shown here is so popular over 700 have been sold and in different versions.
Because the development was made with limited funds, mass production was not an option and although the price was £115 per unit, the sale of the product was not profitable.
It did however demonstrate that HIC could come up with innovations that solve a problem and that the public buy.
The radio headphones were bought in from other sources.
What is amazing is that we had to design the electronics of the transmitter to be compatible with virtually all makes of detector.
This allowed us to get a UK Patent on our product.