Why do digital radios use more electricity than analogue ones?

So much more economical ... analogue radio. Photograph: Simon Smith/Getty Images

Why do digital radios use so much more electricity than analogue ones? We use our two digital radios for about an hour a day each, and need to recharge their batteries once a week. We’ve had several analogue radios over the years and their batteries have lasted for months.

Lawrence Greenberg, London N14

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