HP 34401A Remote Calibration Procedure - Page 1
Forum section: electronics / testgear

author: deepfryed
author_rank: Unknown
timestamp: October 03, 2023, 10:25:13 am
content: I'm reading through the remote interface reference to understand how calibration adjustment is done over SCPI and am a tad confused. I initially assumed the process for the 10V range would be to connect a 10V source and thenCALIBRATION:SECURE:STATE OFF,xxxxxFUNCTION "VOLTAGE:DC"VOLTAGE:DC:RANGE 10CALIBRATION?and then reading a bit more, I understand it's more likeCALIBRATION:SECURE:STATE OFF,xxxxxCALIBRATION:VALUE 10.00000CALIBRATION?Would someone knowledgeable be able to clarify ?Also if the voltage reference used has a known offset, is it possible to compensate for that in adjustment ? I'm playing with a recently acquired 34401a, last calibrated in 1996 that will be sent off to a local cal lab in the next few months. I would like to play with SCPI / remote calibration and learn a bit before that.Thanks

author: coromonadalix
author_rank: Super Contributor
timestamp: October 03, 2023, 12:07:24 pm
content: iif i read page 96 ... 110 ... and 146 .... you seem righthttps://web.mit.edu/6.101/www/reference/HP34401s.pdf

author: alm
author_rank: Super Contributor
timestamp: October 03, 2023, 12:39:03 pm
content: Reading the manual, I'd say: unsecure, set function and range, apply signal, cal:val with actual value of signal, and then cal?. Do this for all the values, functions and ranges listed in the adjustment procedure in the service manual in the given order.

author: deepfryed
author_rank: Unknown
timestamp: October 04, 2023, 01:40:47 pm
content: Quote from: alm on October 03, 2023, 12:39:03 pmThanks Alm, that looks like it. I need to get a stable 1V and 10V reference for the full range calibration but it looks like it can be within 10% of that for adjustment. So in theory as long as they're stable references, I can hook them up to my other 34401a that is more recently calibrated at the same time and do an adjustment. Not sure it's a great idea, but I'll note down the values for historical records before adjustment.Also the US Army Technical Bulletin TB 9-6625-2315-24 details the manual steps very nicely, hopefully someone else finds it useful.

author: coromonadalix
author_rank: Super Contributor
timestamp: October 04, 2023, 03:01:09 pm
content: here it is for the people

author: deepfryed
author_rank: Unknown
timestamp: October 05, 2023, 06:15:26 am
content: Heh, I wasn't sure if the TB's supposed to be public domain. I found it on the back of a truck on the internet somewhereThanks

author: robert.rozee
author_rank: Frequent Contributor
timestamp: October 05, 2023, 12:35:31 pm
content: Quote from: deepfryed on October 05, 2023, 06:15:26 amfrom:https://armypubs.army.mil/ProductMaps/PubForm/Details_Printer.aspx?PUB_ID=1007784"Security Classification UNCLASSIFIEDDist Restriction Code A APPROVED FOR PUBLIC RELEASE; DISTRIBUTION IS UNLIMITED"also seems to be available for download here:https://www.kennethkuhn.com/hpmuseum/scans/34401a_mil_cal.pdf(many others calibration docs:https://www.kennethkuhn.com/hpmuseum/scans/)and readable in a web browser here:https://electroniccalibrators.tpub.com/TB-9-6625-2315-24/and another version here:https://electroniccalibrators.tpub.com/TB-9-6625-2315-35/cheers,rob :-)

author: coromonadalix
author_rank: Super Contributor
timestamp: October 05, 2023, 01:13:06 pm
content: yeah thks for the clarification i did not put ..... while sharing the PDF