Re: [volt-nuts] easy 3458A AC calibration
I used a Fluke 5100B and 8920A for my SCAL calibration. I got lucky and it passed at Agilent. I think if you use a 3325A , you should get results that are close. Todd Sent from my iPad On May 20, 2015, at 15:46, Electronics and Books via volt-nuts volt-nuts@febo.com wrote: It is stated that the ac calibration of a 3458 is so difficult. at least the equipment mentioned is so difficult to obtain. but look what you need. a hp signal generator 3325 where i have a pile of (any other good generator will do to), an other hp 3458 and 3 different thermocouples. very expensive nowhere to be found and very delicate. hp not procduced them for 40 years or ballantine which cost more then the meter your calibrating. but now for the accuracy. the signal generator has only 3 digits of amplitude resolution. if you see the accuracy in the hp protocol what to measure it is not possible to generate that. and for the thermocouples. they give only millivolts. you need an other 3458 with no offset or better a nanovolt meter to measure them. a far easier solution is a hp powersensor 8482a on a hp power meter. it is a thermocouple of the correct frequency range and can be measured accurate enough for the generator. the ac calibation is not an exact value as the volt or resistor but only a deviation in the frequency range. it is even difficult to obtain the deviation in 3 digits. ok it took me an hour but then i was done. Regards Frans i...@electronicsandbooks.com Netherlands Discere ne cesses ___ volt-nuts mailing list -- volt-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/volt-nuts and follow the instructions there. ___ volt-nuts mailing list -- volt-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/volt-nuts and follow the instructions there.
[volt-nuts] 3458A resistance calibration
my 3458 was getting troubles with the calibration of the zero. As volts where no problem and ohm were pretty accurate, my conclusion was that there is basicly nothing wrong. the calibration stopped at the ohm-10. so it must be in the sense lines somewhere. on de dc print there where 2 big resistors (Dale ?) in the sense lines. with a magnifying glass i could spot litle cracks in the solder. after heating with some fresh solder the fault was over. i have red several times that the standard resistor for ohms should be of a better type. In my 1998 production unit it is a vishay vhp101 40k. that must be one of the better ones that were made by vishay. in an older 1994 unit there was no brand or recognisable type code on it. Regards Frans i...@electronicsandbooks.com Netherlands Discere ne cesses ___ volt-nuts mailing list -- volt-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/volt-nuts and follow the instructions there.
[volt-nuts] easy 3458A AC calibration
It is stated that the ac calibration of a 3458 is so difficult. at least the equipment mentioned is so difficult to obtain. but look what you need. a hp signal generator 3325 where i have a pile of (any other good generator will do to), an other hp 3458 and 3 different thermocouples. very expensive nowhere to be found and very delicate. hp not procduced them for 40 years or ballantine which cost more then the meter your calibrating. but now for the accuracy. the signal generator has only 3 digits of amplitude resolution. if you see the accuracy in the hp protocol what to measure it is not possible to generate that. and for the thermocouples. they give only millivolts. you need an other 3458 with no offset or better a nanovolt meter to measure them. a far easier solution is a hp powersensor 8482a on a hp power meter. it is a thermocouple of the correct frequency range and can be measured accurate enough for the generator. the ac calibation is not an exact value as the volt or resistor but only a deviation in the frequency range. it is even difficult to obtain the deviation in 3 digits. ok it took me an hour but then i was done. Regards Frans i...@electronicsandbooks.com Netherlands Discere ne cesses ___ volt-nuts mailing list -- volt-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/volt-nuts and follow the instructions there.
