The input and output buffer once again uses the LM358. I went with two 3.5mm jacks, since 1/4" jacks probably would make it hard to put the business card in a wallet. The final section to design is the power supply.
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A project log for VU Meter Business Card
Simple VU Meter in a business card form factor
The input and output buffer once again uses the LM358. I went with two 3.5mm jacks, since 1/4" jacks probably would make it hard to put the business card in a wallet. The final section to design is the power supply.
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