The pre-amplifier KE83-92C seen in this page is my third and final attempt in designing a modern, good while cheap RIAA-amplifier. The supply consists of a common AC/AC adaptor where old fashioned 10-fold multification has been used for mains supply whereas heater supply has been halfwave rectified. All supply parts is external to amplifier which supresses output hum to a minimum. Grid bias (Edison Effect) is used for simplicity. The chassis is actually made of a turnedover Tunafish-can. The tube will have to be shielded when used as MC-preamp.

Main Data:
Power Consumption: 3W@12V/50Hz
Supply Voltage: 150Vdc/3mA
Heater Supply: 12Vdc/0.15A
Pick-Up Sensitivity: 5mV@47k//150pF
Noise Level: 5mVpp/50Hz (unshielded)
Miscellanous Outputs (hardwired):
1) MC-out: 2380mV@330R
2) TV-out: 476mV@330R
3) MM-out: 127mV@330R

KE83-92C, Roger's Pre-Amplifier Mk III using Sovtek 12AX7LPS's.

More info:
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KE83-92C, Mk III Circuit Diagram
KE83-92C, Mk III Component List
Pre-Amp Bottom View