, Project page and my Journal.
My new home made CAL Box, my Calibration source box. (I used this to calibrate some DMM meters and my HP 2430 scope super easy.) $35? total cost?
10.000000vdc , LT1236, chip. (5mV accuracy and 2PPM/C
10.000000mhz , 7400B2A1 chip, device ±1ppm 0 to 50C (I sync'd it to WWV)
and precision adjustable PSU DPS3003 device below ,voltages from 0 to 34vdc.. 10mV resolution, 0.5% +1 digit accuracy, & digital controls. (imported from CHINA direct, ebay)
I use a 5 digit DDM to get more accuracy, if need better that 10mV accuracy from the 3003. (my scope needs 0.200v cal point so I use my DDM to attain that)
Above 3 devices and 1 each below.
Ready to start wiring it up, power cord and fuse last.
Programmed to 30.00 volts, works great, It does not drift at all.
Below hot wired hack is just to test for 1 minute, while fuse holder arrives.
I have always wanted some thing like this , now I have it.
Before this ,I played with voltage divider resistors, the long hard way to get the voltages I needed, and accurate metal film types. (stable)