The Touch-Radio was, design-wise, by far my easiest project to date. This was for the simple reason that it’s essentially the circuit board out of an old transistor radio, more or less unaltered!
I had had the radio for about 40 years: about 20 years ago, I took it out of its case – which has subsequently disappeared – and rewired the tuning and volume controls, evidently intending to do something with it.
I forget now whether I ever did – probably not – but I found it again recently, just as I was finishing the Cracklephone, and thinking about touch-controlled sound-makers; so I decided to connect a battery clip and speaker and see if it made a noise.
It did! And I soon discovered that by touching certain parts of the exposed circuit board interesting sounds could be coaxed out of it – often not entirely unlike the Cracklephone, but with an element of speech incorporated. Touching the aerial did frequently amplify the received radio signal, but it was rare for speech to become readily intelligible.
So I decided to leave it at that! – apart from putting the speaker, volume control and power in a box, to keep it neat. A PP3 battery would just about fit inside, but it also has a socket for external power.
I’d recently obtained some small plastic jewellery boxes, which looked good for small projects (some more are described elsewhere in the blog), so I used one of these. There was also room for two 3.5mm sockets and two 4mm banana sockets, which I added, as I had done for the Cracklephone, to allow a microphone to be attached to the Touch-Radio or the Touch-Radio to be connected to an external loudspeaker.
I’ve always been interested in manipulating speech sounds, and have a number of projects in mind utilising radios in different ways. I haven’t started working on these yet, but the Touch-Radio is the first in the series.