The copy reads:
Cannot resist sending you our latest spoof photo. Title: "Evaluating a transistor record player"!! The joke is that I'm beating time with a pencil and reading a score. A sort of Semi Conductor! Get it? Hope you can use it - and would you make the Postal order out to Cocklehampton Central P.O this time please?
Beneath that is the reply:
Thank you for your desperate joke. We could certainly use it. But what for is a little difficult to say. You see we would like to get in a mention of our Q-band mixer diodes and low-noise preamplifier transistors as well. We make a wide range of semiconductor diodes - and we want people to ask us for them.