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PREAMPLIFIER CIRCUIT FOR EQUALIZATION OF 78rpm RECORDS (and older microgrooves)

I enclose two gifs of the main circuit, and the feedback loop. I'm afraid the image quality is less than perfect: they were taken from a photocopy of a hand-drawn circuit, which I scanned (using my fax machine!) and converted to a gif. However I think you will be able to read all the component values, which is what matters. As far as I know all the components are still readily available, except that one or two elecrolytic capacitor values are no longer made - just use the next highest.

Main circuit

Feedback loop

No warranty is expressed or implied as to the suitability of this circuit for this or any other purpose. I regret I can't offer technical support or answer technical questions about this circuit.