Hi

I am trying to build a variable power supply between 0-35v using 9V batteries. I tried to make this using a potential divider but i need to keep the current as low as possible. So am not sure about it. please help, thanks.

 

You may try this way:
9V batteries → MC34063 StepUp(Raising Voltage) → potentiometer → MOSFET → Vout

Google MC34063.

 

All I need is a simple power supply preferably using just resistors to apply a bias to a piece of equipment that i am using for a short period of time

 

In order to keep the voltage constant with different loads, you are going to need some sort of active device.

Have a look at this IC and the circuits in the datasheet.

 

This should work as long as the load current is much less than 3.5 mA.

 

I'm not sure how much current you need, the basic circuit already done, you can adjust the values of resistors to suit your need.

The Sw1 is designed for when the batteries is decreasing, then you can switch Sw1 on to increse the voltage.

R4 is the false Load.