Multi-dys-functional

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Pictured is the little circuit board I ordered a few days ago from a 'British supplier' on eBay for the stupendous outlay of £4.33 including postage. I've not had time to check it out yet as Jane, No.1 Son and I have been out for lunch today for my birthday - don't ask which one - at The White Eagle, Rhoscolyn, and very nice it was, too. The device shown is a function generator outputting sine, square and sawtooth waveforms from a few hertz to around 100 kHz. It is built around an ICL3038 IC, which is essentially a voltage-controlled oscillator which found favour with synthesizer builders a number of years ago. The original manufacturer discontinued production a long time ago, and original chips were changing hands for daft money on eBay, etc., until the Chinese got into the game.

I've no idea of the quality or reliability of the things, and I really don't understand why the individual chips sell from similar sources for three times the price of the above deployed item, plus postage. But then, modern commerce at this level doesn't make much sense anyhow, anyway. When I get around to hooking this thing up, I'll post my findings. Meanwhile, on the 'mule' speaker baffle front, it looks like I'm going to have to apply the second, inner ply lamination, as the differential absorption of atmospheric moisture was evident after I unclamped the glue-up this morning: a noticeable 0.5mm deflection at the centre of the piece, due to the plywood absorbing marginally more moisture than the particle board. So it looks like it's going to be a 40 38mm thick baffle after all! Keep you posted...

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