Oscope, Func Generator, Power Supply Calibraton using 0.01% 10V ref?



I have 3 pieces of equipment (Tek 3032B oscope, Agilent 33120A function
generator, and HP 6625A power supply). Each device was purchased used
from different places. None of it has been calibrated lately (and I
don't know if any of it has ever been calibrated). I was wondering how
much calibration I might could do myself. Lets take voltage for
example:

I came across a voltage reference from Analog devices that provides a
+- 0.01% accurate 10V output
(http://www.analog.com/UploadedFiles/Data_Sheets/33869433321179AD588_d.pdf).
That's just 1mV in 10V! Would it be wise to calibrate my 3 devices
to this reference? Or is this a bad idea (i.e. are my devices likely
to be closer than that right now?)? I've never had equipment calibrated
before and therefore I do not know what to expect.

The right answer is to send the devices off and having them fully
calibrated by a service that specializes in that. I imagine they
calibrate over a range of voltages, frequencies, and maybe even
temperatures. I hope to do this when funds become available. However,
I was wondering if the $20 chip mentioned above might not be a good
poor man's calibration scheme. Does this seem reasonable?

Thanks
Stephen

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