On 29 December 2012 20:01, Jeff Machesky <jeff@...> wrote:
Thanks Dave, I actually have watched those videos. Bit drawn out like
most of his videos..but still good. Too much detail is not always a bad
thing.
I thought the bit showing the noise on the DVM was a bit silly when it
was connected to a DC power supply.
As for the 3457A, if it works I plan on getting it calibrated by Agilent
within the year. From what I understand it's about a $200 US investment.
The meter was last calibrated in '98, so I'll be curious to see how
accurate it is when I get it.
I think the calibration service you chose might dictate whether you
get data about the condition when sent.
When I send mine in for cal, I'd like to know what was out and by how
much. But I'm not going to pay extra for a calibration service that
provides that. As far as I'm concerned, if Agilent calibrate it, then
it is OK. For me personally, it makes no difference whatsoever if it
has ISO, NIST or whatever calibration. But I'd prefer Agilent to
someone else.
I have calibration certificate here for an Agilent VNA calibration
kit. It was done by a calibration house in the USA. But from what I
can gather from reading the documentation, the equipment to calibrate
them is not available commerically. So it makes me wonder how a lab
can calibrate a cal kit, when the equipment to do it can't be bought.
I suspect there is a fairly cosy realationship between some test
equipment dealers and calibration facilities.
I plan on purchasing some
voltage references from the well known site as a basic test of the
3457A. I may even calibrate it based on those references if it's way out
and later getting it NIST traceable calibrated.
I don't know if there are pots in there you can adjust with a trimmer,
or if it is all done electronically. You might find it is impossible
to calibrate yourself.
I never had any reason to look inside mine.
Dave
