[time-nuts] Precision voltage to current conversion

[Mark Sims]

I recently picked up a Fluke 515A meter calibrator.  It puts out 0-10V AC/DC (and 100V fixed) suitable for 4.5 - 5.5 digit meters.  The DC voltage source impedance is around 300 ohms.  I would like to build a (reasonably simple) converter to allow current ranges to be calibrated to around the same level of accuracy.  A simple single op-amp floating load converter might do for low currents (I have some 0.001% 1K resistors that would make a nice 1ma/V converter).

Can anybody recommend any other circuits?  Also circuits for higher load currents?
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