Phono Transfer System Construction Information

Construction information for DIY projects, including the MS Mid Side Matrix, Elliptic Equalizer, Mastering Console, Phono Transfer System, Insert Switcher and the Dual Class-A Amplifier. You can post your baby pictures here.
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mediatechnology
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Flat Moving Magnet Preamp Input Capacitance

Post by mediatechnology » Tue Feb 12, 2019 3:17 pm

Just measured the Balanced Flat Moving Magnet Preamplifier stray PC board capacitance without any added termination.

Differential: 4.6 pF plus op amp typically 2-5 pF.
Common Mode: 9 pF per leg both within 0.2 pF of each other plus op amp typically 2 pF.

With the cart connected to the input using a balanced/floating configuration the load capacitance, without added termination or cable C, would be about 10 pF plus the op amp.
Jumpers can then add 50, 100, 150 and 200 pf.

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mediatechnology
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Location: Oak Cliff, Texas
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Re: Phono Transfer System Construction Information

Post by mediatechnology » Mon Feb 18, 2019 5:56 pm

Update February 18, 2019. Updated RIAA EQ Monitor Switcher assembly instructions with test procedures and schematics.: https://proaudiodesignforum.com/images/ ... 021819.pdf

Image

Full size schematics are in the pdf.

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