Another digit (and about 12dB higher price) - you're in another league!
@jackinnj - Pierre Curie ;-)
jan
Just bought an old fluke 8050a bench multimeter for £90 and it's still working though the old LCD's digits look a bit fuzzy.
I bought it because it reads RMS ACv upto 50kHz with good accuracy (0.5% to 10kHz) The instruction manual covers calibration which I might get around to one day.
I also bought an equally old Tektronics TDS210 two channel LCD scope for £135. Fully working apart from broken / mssing knobs for the horizontal position and trigger level. (the seller supplied some 3d printed replacements).
I bought it because it reads RMS ACv upto 50kHz with good accuracy (0.5% to 10kHz) The instruction manual covers calibration which I might get around to one day.
I also bought an equally old Tektronics TDS210 two channel LCD scope for £135. Fully working apart from broken / mssing knobs for the horizontal position and trigger level. (the seller supplied some 3d printed replacements).
It's unfortunate that they chose to put the buttons you use the most on the touchscreen. I don't see my HP 34401As going anywhere. I have a Keithley 236 source meter for when I want to measure gnat farts. 🙂 I scored the Keithley at a surplus auction at TI back when I worked there.
Nice meter, though. I'm curious how they get any sort of precision with 2-wire resistance measurements down to 10 µΩ, though. Just the probes will be orders of magnitude higher than that.
Tom
Nice meter, though. I'm curious how they get any sort of precision with 2-wire resistance measurements down to 10 µΩ, though. Just the probes will be orders of magnitude higher than that.
Tom
That's what I was thinking. And I really appreciate the instant-on of my multimeters. These days it's only getting harder for me to find the time and energy to actually tinker with the stuff, so I'm far away from switch-on-in-the-morning and switch-off-in-the-evening like in the workshop at work. Guess I'll stick to my ICL7135's a little longer then. A 34401 would be much to my liking, I think, but getting a used one up to working order will make for a project of its own - fun though 😉
The HP 34401A is actually surprisingly affordable. I paid $400 for each of mine, calibrated, during the 2008/09 crash. Equitech currently has one posted on Used-Line for $550. I've dealt with them before. They're reputable.
Tom
Tom
I am still not that nerdy that there would be no real people around me who say hello once in a while. 😉
Regards
Charles
I take the tittle is provocative.
Jan is an experienced and practical person.
If the low level measuring capabilities is the attraction point, we have to remind to ourselves that there are more things to arrange for to properly make low level electrical measurements besides possessing an appropriate measuring instrument.
🙂
George
Jan is an experienced and practical person.
If the low level measuring capabilities is the attraction point, we have to remind to ourselves that there are more things to arrange for to properly make low level electrical measurements besides possessing an appropriate measuring instrument.
🙂
George
When the electrical property, resistance, inductance and capacitance, to be measured is very low, the measurement itself cannot be straightforward. The measurement has to account for parasitics and that can be difficult to do.
Wires, PCB tracks and anything through which electrons flow, set up a magnetic field which results in self inductance. Furthermore, any two surfaces form a parasitic capacitance, and finally, any conductive material has resistance. These have to be accounted for.
What I want from a multimeter is reasonable accuracy and reliability.
Wires, PCB tracks and anything through which electrons flow, set up a magnetic field which results in self inductance. Furthermore, any two surfaces form a parasitic capacitance, and finally, any conductive material has resistance. These have to be accounted for.
What I want from a multimeter is reasonable accuracy and reliability.
An electrometer has been on my list for years, but I've not yet come across an affordable one in good condition.
Not that I really need it of course 😎
Jan
Not that I really need it of course 😎
Jan
If by electrometer you mean an electroscope, that can be made. House it in a jar with an insulating lid, make an L shaped hook and use kitchen aluminium foil for a detector. You may use gold foil if you want more sensitivity.
When my standard cell died (yes they do run out of steam) I replaced it with a modern solid state voltage standard. I also picked up a frequency reference that is easily checked by a receiver and WWV at 10 MHZ and outputs a number of useful frequencies down to 1 hertz. I do have a few .001% resistors, that have to be handled by tweezers to avoid heating them before use. Floating around here somewhere reference capacitors and inductors, that I picked up when an interesting calibration lab closed. My Genrad 1658 bridge is old, but still sits on my bench and so far agrees with my standards values.
For those who know what it is, I have a piston-phone, with a barometer.
I do have a few mirrored meter movements that project the line of measurement on a screen. Even was able to find a replacement light bulb for one of them!
I won't even get into my collection of vacuum tube voltmeters...
Now all of that ancient stuff cost less than your new-fangled meter!
Do let me know what the calibration interval is and the cost to do it!
Do I even need to mention almost all my measurements today are done with my Fluke 85-3! (First two Flukes I had walked off a jobsite 🙁 )
For those who know what it is, I have a piston-phone, with a barometer.
I do have a few mirrored meter movements that project the line of measurement on a screen. Even was able to find a replacement light bulb for one of them!
I won't even get into my collection of vacuum tube voltmeters...
Now all of that ancient stuff cost less than your new-fangled meter!
Do let me know what the calibration interval is and the cost to do it!
Do I even need to mention almost all my measurements today are done with my Fluke 85-3! (First two Flukes I had walked off a jobsite 🙁 )
Almost forgot, to make really low level measurements, I use a very low noise amplifier. It is made from many paralleled low noise amplifiers. But I do need to change out the now faded original rechargeable batteries.
For low level DC I have a Keithley 148 (10 nV full scale), for AC I have a transformer input amp to get to pV/rtHz.
You guys are becoming voltnuts. . . I have been there long enough to need institutionalization:
Primary DV reference Fluke 732A (will need a cal check soon but trustworthy to 10 PPM at least)
AC transfer through thermal converters to Optimation AC110 calibrator (120V 10 Hz to 1.2 MHz).
Meters Keithley 2015 on the bench, Prema 6001 and Fluke 8506A in the cal space. 6 1/2 except the Fluke is 7 1/2 for DC.
Also RF stuff etc.
If you wait and watch you can find most useful stuff for under $300. All the above and lots more.
I need to cull the herd soon. Would there be interest here in oddball and/or useful test equipment? Most is too big to ship economically so local pickup.
You guys are becoming voltnuts. . . I have been there long enough to need institutionalization:
Primary DV reference Fluke 732A (will need a cal check soon but trustworthy to 10 PPM at least)
AC transfer through thermal converters to Optimation AC110 calibrator (120V 10 Hz to 1.2 MHz).
Meters Keithley 2015 on the bench, Prema 6001 and Fluke 8506A in the cal space. 6 1/2 except the Fluke is 7 1/2 for DC.
Also RF stuff etc.
If you wait and watch you can find most useful stuff for under $300. All the above and lots more.
I need to cull the herd soon. Would there be interest here in oddball and/or useful test equipment? Most is too big to ship economically so local pickup.
Is there a forum for DIY equipment, rather than DIY audio ?
Sounds like a lot of fun, be it for different audiences.
😀
Patrick
Sounds like a lot of fun, be it for different audiences.
😀
Patrick
Hi,
You might have a look over at the EEVBlog .... projects section.
jauu
Calvin
ps. just don´t out yourself as one of those highend geeks. 😉
You might have a look over at the EEVBlog .... projects section.
jauu
Calvin
ps. just don´t out yourself as one of those highend geeks. 😉
I think we are heading to the right direction.
Experienced members are welcomed to provide instructions, valuable hints and tips over the way sensitive bench electrical measurements should be conducted.
Ways to minimize mistakes, proper set-up and ancillary equipment for to minimize environmental influence (E, M, T cages) as ways they use to verify their measuring equipment, all with a diyer in mind (not a Primary Cal Lab).
George