Dear Learner,
the values reported by BigMac are absolutely typical: you do not really needed to measure these values to guess them. What isn't typical is the problems you are experiencing to achieve a faily regulated low noise 3.3 or 3.5V supply with less than 50 or 100mA from an unregulated input which may be some rough 10-14Vdc + 1Vpp ripple (or so).
The best solution at all would be a 3 terminal regulator like the cheap LP2950CZ-3.3 or the better LP2950ACZ-3.3 (1.5% max error: didn'you need a good precision and stability?) which may work with 4 to 30V input, needs nothing but 2 capacitors at the input/output terminals (330uF/16V and 100uF/16 are ok), is housed in the handy TO92 package and is self protected.
A possible solution if you are not able to achieve this component is to rely on standard ICs and parts. A good one is the cited uA723 which, despite of his old age (it was released by Fairchild in the 1968!) is still capable of delivering well regulated voltage in the range required at the cost of some 6 resistor/capacitors added to the previously 2 for the 3 terminal regulator. This component needs >9.5V input (12 +/-2V is ok) and is capable a 5% very stable output which may be easily trimmed to 0.5% with an added trimmer on the reference input.
Another very good solution I used is based on the cheap TL431 + 1 small transistor and a bunch of resistors (4 at all). I used it with precision resistors to achieve <1% error on the output without any trimmer (TL4131A is needed in this case) or with a small added trimmer to slightly adjust the output voltage.
If you need I will be glad to provide some diagrams, provided you states min-max input voltage, input ripple in Vpp, max regulated current (50mA?) and the desired output.
Regards from an old boy.
Encoder