tl431
Hi.
The TL431 is an excelent shunt regulator, very low noise. by the looks of the series resistors and the voltages you've measured total current draw from the 12V is about 130mA ish. a 0.2A supply at 12V should do fine.
An important issue is keeping the rectifier noise low, at these currents use 2 1n4148 signal diodes in parallel for each arm of the rectifier (a series resistor of a few ohms will make sure they share the current.) A small toroidal transformer, CRCRC smoothing will remove any remaining noise and then a cheapy 7812 regulator will do the rest.
If you want i'll sketch a circuit and email it to you.
Chris
Hi.
The TL431 is an excelent shunt regulator, very low noise. by the looks of the series resistors and the voltages you've measured total current draw from the 12V is about 130mA ish. a 0.2A supply at 12V should do fine.
An important issue is keeping the rectifier noise low, at these currents use 2 1n4148 signal diodes in parallel for each arm of the rectifier (a series resistor of a few ohms will make sure they share the current.) A small toroidal transformer, CRCRC smoothing will remove any remaining noise and then a cheapy 7812 regulator will do the rest.
If you want i'll sketch a circuit and email it to you.
Chris