2013年4月20日 · disclaimer: I have never calibrated an HP 3478A, but need to investigate, then calibrate my meter with the standards I can muster up, so I am interested in the process. after doing the performance tests 4-21 (to log results for a plan of attack) First of all, the HP 3478A has 5 ranges for DC voltage, 30mV, 300mV, 3V, 30V, 300V 0 and max for each of those ranges, so your 10V can't apply (except ...

2017年4月3日 · Re: HP 3478A: How to read/write cal SRAM « Reply #18 on: April 12, 2017, 07:46:14 am » @MarkL et all Now we "just" need to reveal the HP3457's secrets PHK did the 3458A , and you did the 3478A Who's doing the 3457A /Bingo

2020年4月10日 · The HP 3478a, on the other hand, will need a battery replacement to maintain the SRAM. Thoughts on either Bench DMM, accuracy between the two, recommendations, etc, appreciate any additional insight on these 2 DMMs.

2020年4月18日 · Hi guys, I've finally received my first bench multimeter, an HP 3478a, that I got for a decent price. As far as I know, it currently still functions, and that I need to replace the battery.

2013年5月5日 · I took a different approach with my HP 3478A. Now that electroluminescent tape and inverters are so cheap on ebay, I decided to give that a shot. I'll call this a mild success, with two caveats: 1) The LCD glass is polarized, which means the EL tape won't be as bright as you'll expect. As it was, it is just bright enough to make this worth ...

2013年2月21日 · Re: EEVblog #427 - HP 3478A Multimeter Teardown « Reply #22 on: February 23, 2013, 12:46:23 pm » Dave mentioned the measured voltage was at 3.49 volt which is a big possibility it is a lithium thionyl chloride type (LTC) with typical at 3.6 volt instead of lithium sulfur dioxide type at typical 3 volt.

2017年1月15日 · When the Prologix is connected to the HP 3478A, if "++read" is sent, does the meter return the value continuously or only just a single read? Thanks for any help anyone can provide! I hope to publish the source code on GitHub for all to use once it's done.

2018年3月13日 · Just found something hidden in plain sight : the HP Journal, 1983-02 issue, has an article about the 3478A, which is presented as the "HP-IB version of the 3468". They mention a few things about cal : - offset is applied to raw ADC reading, *then* gain factor is applied.

2018年11月15日 · Re: HP 3478A: How to read/write cal SRAM « Reply #93 on: January 19, 2020, 05:39:59 am » Thanks to code provided by steve1515 I've now added the ability to edit the gain and offset for each calibration entry into my HP3478A control program.

2014年3月24日 · Re: New (old) HP 3478A with a very floaty volts range « Reply #21 on: March 24, 2014, 06:35:01 pm » For comparison, here is my Keithley 2015 (6.5 digits / 1000000 counts, 50 ppm + 35 counts on 100mV range) and 2001 (7.5 digits / 20000000 counts, 37 ppm + 120 counts on 200mV range).