Well, as promised, here's a (brief) report on the Agilent DMM logger interface.
Wow....you sure were motivated to get this working, well done !!
As for me I probably would have thrown both meters in the trash out of anger and despair !
You remind me that I need to make a serial IR cable for my old Metrix DMM 53/54/56. It's unobtainium, need to make your own.
Far too much time and money invested to give up now...
As for making an IR-serial cable for your MX's, that's quite a project, unless there's schematics and firmware available. No chance of finding one at all?
No chance whatsoever. Not worth wasting anytime trying to find one.
It should not be difficult to make one. There is a thread for these meters here somewhere and some guy said he made his own and was easy. A friend this week also made his own cable without trouble.
I actually want to make one if just for the fun of designing and building it, the joy of making something that works (hopefully !) . Using it for something useful is only icing on the cake !
It's not USB it's just simple RS232. The bench version of this meter uses the same PC S/W, and it's basically the same meter inside.. .just in a bigger box...
Have the manual for the bench version, remember the other day I scoped its RS232 output with the HP MSO.
So I have the details I need... it's full duplex, +/- 12V voltage levels, and speed is 2400 Baud which is super slow so should not be hard to get the IR bits working at that speed.
Just need a jelly bean IR LED and Photo transistor or Photo diode, of a diameter that fits inside the holes in the DMM. Need to figure out what wavelength the IR LED uses in the DMM, for better results, but that's about it I think...
Could just ask my friend what he did for his cable, but that would take the fun out of it all. Want to design my own, I like designing stuff... simple projects like this are ideal as it's cheap and quick to do, and the chances of success / reward are high... which keeps you motivated to then work on the next project on the list !