Surprised no-one has mentioned the Project Books from the 1970's yet.
http://www.woolworthsmuseum.co.uk/st...jectbooks.html There was "Build your own Crystal Set" and "Build your own Transistor Radio". The most complex set in the "Build your own Transistor Radio" book was a reflex/regen set. Does anyone know who the author was for these?, we know the Ladybird "Making a Transistor Radio" was written by the Rev. George Dobbs, but the Woolworths Project books were, as far as I know, not credited. There was also "Build your own computer" and "Experiments with Electricity" Incidentally, I had forgotton about the scales until they came up on here, and how they would carry on weighing for 1 penny until you got off. You could weigh as many kids as you liked so long as one got on before the other one got off!