TA-0433: LM399H Boxed Voltage standard Calibrated - Test Teardown

[@User-rm9cw]

Hi Tony! Thank for review 👌

[@TonyAlbus]

Thank you!

[@sdgelectronics]

Looks great, will have to get hold of one of these. I still have an LTZ1000ACH sitting in a box that I need to do something with too

[@TonyAlbus]

Thanks! , yes nice projects are available for the LM399 and LTZ1000 but some are now making the jump to ADR1399 , stay tuned :)

[@redsengineering]

Looks great, thanks for the review.

[@TonyAlbus]

Thank you Red!

[@MarcelHuguenin]

Hey Tony! Lijkt een mooie build indeed. En nog nauwkeurig ook en de boost converter om hem vanuit USB-C te kunnen voeden. Goeie review!

[@TonyAlbus]

Dank je!, ja zeker een leuk ding voor de prijs helemaal.

[@three-phase562]

Looks good value for money. I would likely struggle to build it for that price in the UK.

[@TonyAlbus]

Yes indeed, popper connectors and box, the PCB itself also looks good. yes for that price we can not build that.

[@davidv1289]

Thank you for the review and look inside, Tony. As others have said, the problem with adding a potentiometer is tempco. Did you notice what the shield is connected to (USB ground?) and is the output low tied to it as well? Could be a source of noise depending on how you power it. Regards, David

[@TonyAlbus]

Thanks David, yes indeed, powering it with your PC might not be a good idea. powerbank or better a linear PSU also bypassing the StepUp converter.

[@johnfitzpatrick2469]

Merry Christmas Tony from Sydney Australia. Like the USB meter. As a beginner, my focus is on a variable power supply for all DC repairs needs. However, I can see; where * buck boost converters, etc are needed for permanent supply e.g 240VAC -19-24VDC LCD TV 🎄🌏

[@TonyAlbus]

Thanks, merry Christmas to you too!

[@zdzisiek1979]

Ciekawe urządzenie ... Pozdrawiam

[@TonyAlbus]

Thank you!

[@drewwollin3462]

The newer standard ADR1399 is available as an evaluation board for about US$50, ADR1399H-EBZ.

[@TonyAlbus]

Thanks! yes something like that is coming soon :)

[@bobuhi]

Good video. Can you measure the SMPS switching noise (at ~MHz on oscilloscope) for a light allowed load?

[@TonyAlbus]

Thank you sir, if you don;t trust the Step-Up converter, wich is a good point. you can use 2 9Volt batteries or a linear powersupply to power it. Altough i did not see much noise on the output.

[@grabi7387]

I love and hate this kind of video and the Mailbag videos. Now I've ordered another toy.😅

[@TonyAlbus]

Oh yeah, i know that feeling.. LOL

[@barrybogart5436]

Thanks. I ordered the Cal version. I already have an LM399 board, but it requires 12V wires and uses jumpers to choose the voltage. How long do you think, at 20C do you have to wait for stabilization? I do have a USB meter to monitor it. 73

[@TonyAlbus]

Hi, i think it said 30~60 minutes, but within 15 minutes it was very close to stable in my 20~21 C lab. 73

[@ivolol]

I would compare the noise against your DMM check plus, and you might have a previous LM399 reference? Nowadays the noise of LM399 is nothing special. ADR1399 is much better. But the stability is still top class. Yes I would be worried about adding to tempco by adding a 100ppm pot. To adjust it, I would use an outside potentiometer just to find close resistors to use and then solder the fixed resistors. 25ppm MSD not hard to find as well as 10ppm. But by adjusting, you are also losing your calibration.

[@TonyAlbus]

Yes i will leave it as it is indeed. i will have a look at the ADR1399 soon

[@piotr-Garou]

👍

[@TonyAlbus]

Thank you!

[@AlpineTheHusky]

Ok now Im really weirded out. I have recently gone down the LM399 rabbit hole and suddenly other people started talking about it again

[@TonyAlbus]

Yes they are very popular, its also worth to have a look at the ADR1399

[@zoom_h2625]

Think is not delivering to de… Found another dealer.

[@TonyAlbus]

Great you found an other, for me its hard to see which seller delivers where, i only see if it delivers to me, NL but the item links at least give you a start to look from.