This past week I’ve been helping my dad design some replacement boards for the HP/Agilent 3458A multimeter. I don’t know much about what these actually do, but he says that this board is the heart of the 3458A. Apparently it is some sort of DC reference board which uses the LTZ1000. Anyway the protoypes seem to have tuned out great. He thinks he might try to sell his boards on ebay. The cool thing is that we tried hard to keep everything pin compatible so they should work fine in an actual 3458A or standalone in a project like this one.
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Can you post schematic, bill-of-materials, and pcb-files (or is this just an advertisement)?
Hi Ken, This my own personal blog for projects i complete among other interests. So to answer you question, no, this is not an advertisement. Having said that, my dad is currently testing his prototypes, and does plan to try selling some boards soon on ebay. The HP schematic, which this is based on is known to be freely floating around on the internet. I will say that it is not much different from the LTZ1000 datasheet though, so it’s not like the design is some sort of proprietary secret. Normally i like to make my projects open source and would release the pcb-files, but since both me and my dad spent some effort in designing his own, and since he does plan to try selling some i wont be releasing any of the files at this time.
You said this is more stable than the Agelent design. How stable is it. How do you measure the stability? How long do you have to “cook” a board to get the stability that is more stable than a cooked Agelent board? Is your board better than the 4 parts per million per year (ppm/y) drift or the 2 ppm/y board?
This was mostly my dads project. Try emailing him to find out. smbarney [at] gmail [dot] com.
Any chance you could either post a link to the ebay posting where I could buy these, or release the design files? (assuming it worked as expected, of course.) Looks like it’s been over half a year…Thanks.
I’m actually currently away from home. This was for my dad. I helped him make the boards, but i don’t have enough expertise in electronics to know if he got it working as expected. Last i had heard he did get it working well. Originally we put the chip upside down and had to make some new boards. You could try emailing him at smbarney [at] gmail [dot] com.
Hi Scott, i have one ready to sell. Are you still interested?
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Hi keen,
i have this HP3458A with issue, it couldn’t measure resistors value, could you help to fix this?
Kind Regards
Hicham
Sorry Hicham,
my electronics knowledge is VERY basic at best. I have no experience using or fixing HP3458A. I asked my dad, he said no, but he said if you use Google you should be able to find a repair or troubleshooting guide online. Sorry.
HI Keen101
OK, thank you very much. very kind.
Are the boards available now?
No. I did end up producing 2 or 3 and sold them on ebay as a test to see if they would sell at all. If demand was high enough i could venture into assembling some more or selling bare PCBs i suppose. How interested in the boards are you? It might even be possible i could open source the files.
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