#249

[@stalkerfox]

Прекрасные приборы, мне остаётся о подобном только мечтать

[@TonyAlbus]

Thank you Sir!

[@stalkerfox]

@@TonyAlbus What do you think of the HP 3478A? There is an opportunity to purchase it for $150.

[@TonyAlbus]

@@stalkerfox Hi i did have one, there must be a video of it also. i sold it because i wanted a 34401A it was okey, the display is not always good to read. with LCD.

[@stalkerfox]

​@@TonyAlbusthanks, i will try to find Your video

[@garywashington9391]

Great Video and I will explore the results of my hp 34401A to compare.

[@TonyAlbus]

Thanks!, yes please return with your results, interesting to see.

[@TheDefpom]

Nice comparison Tony, you got the same kind of results I have seen comparing my SDM3065X, Datron 1062, 1082, Solartron 7061, HP 3457A, I personally wait at least 2 hours, ideally 4 hours before considering them stable, if you are really worried about precision then leave them on for 24 hours, and as you observed, ambient temperature is very important.

[@TonyAlbus]

Thanks Scott, yes i think i saw a Datron on one of your videos and fell in love.. that Solartron is also a beauty, hard to find affordable.. great you have the same results, just shows it is indeed needed, if you don't want to heat-up, save yourself some money and buy 4.5 or 5.5 above that indeed ambient and 1 or 2 hours.. thanks for your input also here.

[@TonyAlbus]

BTW great work on that Siglent calibration video.. life saver for a lot of people i am sure.. thanks for your efforts there and sharing it.

[@TheDefpom]

@@TonyAlbus thanks Tony, sharing information to help people is one of the main reasons I make videos.

[@allthegearnoidea6752]

I don’t do precision but interesting to see your multimeter collection and comparisons. Thanks for sharing best regards Chris

[@TonyAlbus]

Thanks Chris!

[@pbk380]

Very nice comparison, even with the very slight differences none of them would affect settings on a radio. Thanks

[@TonyAlbus]

Welcome, thank for leaving a comment

[@SoddingaboutSi]

Hi Tony, have two HP/ Agilent 3401A's in the workshop and also use them at work. What has always impressed me with them is how stable they are. I have never done a temperature drift test but they seem very good indeed. In fact I don't think we have have had to calibrate one ever! Not my meter of choice but as they were repairs from work i'm happy.

[@TonyAlbus]

Hi Simon, yes indeed i fully agree, after i have the 34401A i wonder why i have the others :) .. the Datron because it is cool, the Picotest because i thought it was e keithley, now i know it was a rebrand and keithley experiment , they wanted a entry level.. The Siglent it looks cool.. in the end i prob. use the 34401A as you say.. it just works.

[@tombump6946]

Very interesting. I have an Agilent 34401A and a Siglent S DM3055. I did a similar test connected to my DMM Check Plus. Very similar results. The Agilent was rock solid from the start. The Siglent slowly dropped until it eventually matched the Aglient. Did not factor in temp changes.

[@TonyAlbus]

Thank you for sharing your results too, indeed very interesting.

[@derdoktor7123]

Hi Tony, great video! It‘s so impressive to see how good these old HP 34401A are! As you know I have done the same test between the HP and the Siglent but after keeping the Siglent running for 500 h for a little „burn in“. My HP takes longer to settle down, may be there is some improvement with the Agilent generation? Unfortunately the prices for HP/Agilnet 34401a became so high that I missed the chance to get another one. B.D.

[@TonyAlbus]

Thank you BD...maybe the Siglent needs indeed more time.. i have it not that long, maybe then it settles faster.. yes Agilent secondhand are still expensive.

[@RyanUptonInnovator]

i love this.

[@TonyAlbus]

Thank you!

[@manuelcv9475]

Hello: good video and interesting: The HP 34401A is the best-selling bank multimeter in this world, sure it is for something. As for the test, it must always be taken into account that the internal resistance of the multimeters when the input resistance is less than 10 mohm, so the tension pattern will be affected. Remember that the 34401A has on the menu the choice of input impedance greater than 10 gohm which will not significantly affect most of the tension references. In metrology laboratories, more than 2 multimeters or meters are never connected to the same voltage source because input impedance the voltage degrades and becomes more unstable. The 34401A has a voltage reference with an oven, is a selected LM399H and the more it is used more stable is, that postulates one of its manufacturers, logically until it reaches at the end of its useful life. I still expect a video from Agilent 34401a and its inner views. Greetings.

[@TonyAlbus]

Thank you, yes the test was to see the influence of tempreture not the accuracy itself of a meter and the video and teardown will come of the 34401A

[@MarcelHuguenin]

Hey Tony! Nice test, interessant resultaat!

[@TonyAlbus]

Thank you... i was sloppy with this, now it opened my eyes.. it is needed.. 6.5 is useless if you don't heat up first..

[@davidv1289]

Very nice experiment, Tony. It would be interesting to warm up the Agilent for thirty minutes so it is stable then connect you voltage reference and turn it on - see what kind of drift the reference has - if any. Regards, David.

[@TonyAlbus]

Yes that is indeed a nice idea!

[@la7yka]

Great test Tony.

[@TonyAlbus]

Thank you!

[@ivolol]

I'm not sure why you turned the voltage reference you intended to use, on at the same time as the meters. I would have had it on for an hour before, if that is the stable point you wanted to test against

[@TonyAlbus]

Good point

[@danishnative9555]

Serious question Tony. What are examples of markets in need of extreme precision voltage reference? Military? Aerospace? Nuclear reactors? Ham Radio op's?

[@TonyAlbus]

Hi, i am not even sure... i am a Test Equipment Addict and i started with 3.5 then a 41/2 and have now 6 1/2 digits DMM... if you have 6.5 you want it to be good.. as you know i never do repair ..LOL

[@danishnative9555]

@@TonyAlbus It was a rhetorical question that won't get an answer. I'm amazed you hauled all that gear into the attic via a ladder. Or do you have a dumbwaiter?

[@TonyAlbus]

@@danishnative9555 Yes all trough the tiny hole and little ladder :))

[@WilliamLaakkonen]

To be fair Tony, the Datron is a meter designed in 1979 - thought the 1072 came out around 1980, it was the same basic design as the original 1061. We did all our calibrations at the Datron lab at 23 C with a 24 hour period of climate adjustment. Also, the meters are not rated for highest accuracy at 1/4 scale - but I suspect you know these things. Thanks for sharing!

[@TonyAlbus]

Thanks for sharing that information. i like to test it were i use it, if it is ideal or not.. it is were i work.. and i think it showed you do need to heat it before it is more or less accurate.

[@TonyAlbus]

Interesting... what is 1/4 scale, what does it mean, i did not know.

[@tizianob8590]

@@TonyAlbus I think it means that the datron is in the 20V range and you're measuring 5V (so 5/20 = 1/4 of scale). The disavantage is that the range error will be bigger (34401a has a 10V range so half range error)..

[@TonyAlbus]

@@tizianob8590 Thanks, yes makes sense!

[@ssalient]

I recently bought a Picotest M3500A, but for me, if something is 4.99994 or 5.00009 volts doesn't really matter that much :) It's nice to have decent 6.5 digit multimeter though.

[@TonyAlbus]

Nice pick, it is the same as a Keithley 2100 or Texio DL-2060 or Array M3500A i like its fast...

[@jamestschirhart269]

So I have an Agilent 34405A, Fluke 87V and am receiving a HP 34401A this week, these should be well within the abilities of the DMMCheck Plus. Also, would a Keithley 6517A be function checkable with the DMMCheck Plus?

[@TonyAlbus]

Hi James, nice collection, i see the Keithley 6517A is a 5,1/2 digits, yes that should not be a problem on voltages and current. That keithley is very hi input impedance, cool!

[@MrKrasimirk]

Definitely any DMM which have ovenized Vref requires warm up period specified in the DMM datasheet.

[@TonyAlbus]

Yes indeed, very clear, even in this simple kind of test setup.

[@tizianob8590]

Nice setup! The siglent doesn't look good with all that drift! Was Autozero (AZERO) enabled? Would be cool to ovenize the 5v Reference ;) What about ac voltage? Is siglent right or the reference? Tks

[@TonyAlbus]

Thanks!.. my Siglent is a bit off on AC and teh Datron needs some fixing on AC, was more to see if heat-up is needed or not.

[@karlfell3768]

Not a good idea to parallel all the meters together. The input impedance change will affect the readings. Some meters will be more sensitive to it than others.

[@TonyAlbus]

Parallel or not that impedance will not change over time of testing, the test was about heat-up time and stabilizing , not about accuracy of the meter itself.

[@perrieiles493]

I have both of these, and a 5,000 hour aged LTZ1000ACH to see how they are going.

[@TonyAlbus]

Cool test!

[@sammin5764]

🌹🌟🌹👍

[@TonyAlbus]

🙏

[@РоманОпалев-з8ь]

А я всё стареньким 61Е пользуюсь)

[@TonyAlbus]

Yes the UT61E, nice sir!

[@dennisqwertyuiop]

one on top other generating heat,,do you that has effects?

[@TonyAlbus]

Maybe watch first :)

[@kaybhee6]

goot

[@TonyAlbus]

Thanks!

[@johnshaw359]

A resting human male gives off roughly 100-120 Watts of energy.

[@TonyAlbus]

but i am lazy

[@jerryconrad5251]

Evidently Brymen 869/867/859/857 and Amprobe am-160-a and am-140-a can be calibrated. See mjlorton video of 8 years ago. kzbin.info/www/bejne/jYrLp2BmlMeVhNE

[@TonyAlbus]

Thank you Jerry, that is some great info.. my Brymen is still good now, but great for future adjustments, very helpful

[@djneon12]

you can try to log the measurments with a pi or pc and automaticly make a graph of the all the meters to gether, have a look at MarcoReps his videos, he has a few nice multimeter comparisons. kzbin.infovideos

[@TonyAlbus]

Thank you!.. yes that is a good channel.

[@wojciechrosciszewski]

First ! :D

[@TonyAlbus]

Yes you are

[@wojciechrosciszewski]

@@TonyAlbus I wonder if locking those meters in a very stable temperature environment would be more beneficial for such experiment. Humidity might also be another factor worth considering. Meters might have some dust sucking up moisture from the air, I had this case in one of my old Polish oscilloscope Unitra OS350, where the dust just sucked up so much moisture that corrosion started to develop on quite sensitive components. But... thats just way over the top right ;) I think you've already shown how temperature affects readings. Great video :)

[@TonyAlbus]

@@wojciechrosciszewski You have a point, but i like to test it in a place where i use them :)