By combining 49 of them he’s put together a soda bicarb diode steering circuit for a 7-segment display capable of showing the digits 0 to 9. He takes the idea for his diode from electrolytic ...

I’ve written about the bicarbonate of soda trick before, extolled by many experts in the art of cleaning your home and your carpets, so, calling on my journalistic expertise (no jokes please ...