Phono preamp dissection.

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Could someone elaborate a bit on this phono preamp?
It’s a vintage Sansui schematic.
I own the preamp and would like to understand what happens.
I see two diff pairs and two push pull (?) outputs in series, pin 7 and 8 are externally tied together or attenuated with a resistor/capacitor network to match the sensitivity of the cartridge.
What is the purpose of TR07? Not marked but that would be the transistor in the middle between the two parts of the amplifier.
Where do I find the RIAA corrector?

It would be nice to hear what you guys come up with.

/Hugo :)
 

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May gees is that the first stage which TR01 to TR06 is the MC AMP, and there for has it own Voltage regulator (TR07), helps to get a’ god S/N for MC input stage.

The RIAA stage is R19 to R21 which C07 and the other side off the range is generate by R26 and C08 in the fead back line, the second amp is the MM AMP.

The switch board is some mystery butt, another gees, these tree selection is to generate a load impedance for MM pickups and sensitivity on the MM/MC pickups, so that it will work as god it can with any brand.

Input for MC is when the switch position is set to (1) and MM is for (2) and (3).

//

Thomas
 
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