Fluke 732A DC Voltage Standard & low cost DIY attempt

[@LOOKMUMNOCOMPUTER]

im pretty sure i can make that circuit bend a little worse if you want me too hahaha. :D.

[@In3xorable]

Awesome to see you here! I have been watching reps and look mum no computer for years now! The reference made me smile. Hope to see you here again!

[@AppliedCryogenics]

They should make VFD displays that have 16-segment Pagan runic font... Just for you, my friend.

[@ursanotsomajor]

The "look mum no computer" reference at 10:50 got me good 😁

[@Tjousk]

Indeed

[@pyroman590]

I laughed way too hard at that!

[@sydneybiscuit]

right? shots fired 😂😂😂

[@DouglasFish]

funny enough LMNC music played in Furze's video yesterday

[@pyroman590]

@@DouglasFish Ha! We noticed that too!

[@illusivec]

As someone who doesn't care about any number after the dot in his £10 Chinese voltmeter, I applaud your dedication to getting the 10th decimal of your instruments right

[@IanScottJohnston]

I got a mention!....whoop whoop!

[@flantc]

To calibrate a voltage reference you need two additional voltage references that you rub together in an alternating pattern until they are all with in spec.

[@boobrowsky]

🤣

[@dirtdart81]

That is a niche joke but goddammit it is my niche 😂😂

[@klausluger7671]

I'm sure that jump in voltage in 2020 was just a coincidence, it was otherwise such an excellent year

[@w04h]

It was probably just a... Fluke 😎

[@transkryption]

@@w04hparasites? flukes? in the liver? ewwww!

[@jensknudsen4222]

2020: The Year the Voltage Standards Went Crazy!

[@johnshaw359]

@@jensknudsen4222 2020: The year everything went crazy.

[@nickstanley5064]

Finally, my favourite volt-nut is back.

[@josefonseca9178]

I know Marco, your knowledge about electronics scares me, sometimes. "look mum no computer" was very funny tho. Very nice video.

[@TheMcSebi]

my dear god the 9v and the 1.5v battery in series killed me

[@andrean_7725]

10.5V is way to low to be harmful, I smell you're lying!!

[@Anvilshock]

@@andrean_7725 What if he choked on it?

[@peterfitzpatrick7032]

Eating the vintage foam was a nice touch... 😋

[@power-max]

@@andrean_7725 apparently some marine or sailer guy managed to kill himself with a multimeter on continuity check powered by a 9V battery by shoving the probes under his skin. 🤦‍♂️

[@wesleymays1931]

@@power-max _What?!_

[@PCBWay]

As always, a stellar job, Marco! More to come pls! 🎉

[@ikocheratcr]

Those censored holes, really made my day... Love the gems you put in your videos. All the info is serious, also love it.

[@hypercomms2001]

Memories!! I used to sell Fluke test equipment... and I very much remember the launch of the Fluke 5700 calibrator. That was 1988... man! How time has flown! I remember selling a 5700 to Siemens after I went to their office in Bayswater, Victoria on a "fishing trip" with a Fluke and Philips catalog prospecting for names and opportunities and six months later got this massive order for Fluke Calibration equipment.....

[@deviljelly3]

Nice to have the Electronics "Bernd das Brot" back with another wonderful video.

[@normanmacdonald9411]

That's my new favourite description for this channel...

[@deviljelly3]

@@normanmacdonald9411 "Mist..."

[@deviljelly3]

@@normanmacdonald9411 or... "Bernd das Widerstand"

[@thedanyesful]

It's amazing that you put so much work into these videos while consistently demonstrating your sense of humor. This is some of the best content on KZbin.

[@3beltwesty]

6:28 on the 895a and 887a Fluke the pre regulation voltage is adjusted to 18.0 +/ - 0.1 Volts via a trimmer resistor.. they also say to measure the peak to peak AC ripple on the 18 volt DC. Spec is be less than 200 uV. The 895A differential voltmeter manual is from 1966..

[@hermannpaschulke1583]

That capacitor tweezer is cool :D

[@wesleymays1931]

They're called the Miniware DT71. They look great but they have a couple design oofs

[@matt_gillard]

I was just thinking about this channel. Hope the updates are further apart due to you being good busy and not anything else. We all got day jobs and I appreciate the extra effort to post these vids.

[@elektronikzmbrtlar1586]

Gods have blessed us. All hail the marco gods

[@kingofcastlechaos]

My coworkers asked me what the last video I watched was (this one), and they have promised to never ask again. Thank you for compelling content and actual humor.

[@draco_2727]

Marco, I have zero, I repeat, ZERO idea what's going on here but your content, your knowledge and humor is GREAT! I can only wish I knew half of electronics as you do 🙌

[@angelosntimtsas2201]

By far the most interesting KZbin channel regarding electronics, with a great sense of humour! I always learn something new and actually you gave me a wonderful idea for my next project with the flexible PCBs! Keep it up Marco!! 😉

[@DanielMelendrezPhD]

- "Oh snap! Marco uploaded a new video. Imma watch it!" - Excuse me, we are in the middle of a Zoom meeting... - I know. See ya later! *leaves call* - ...

[@lapissea1190]

I understood a few words in this video. I still found it entertaining. You sir have some kind of magic

[@thiagoennes]

the look mum no computer reference made me spill my coffee.

[@gideonwackers7693]

I kept it contained but it did get into my nose

[@K.D.Fischer_HEPHY]

That came out of nowere, yeah. To be fair, Marco and Sam are both very interesting individuals with a unique skillset.

[@thedreadedone]

as he flipped the board over i said "huh, looks like more like a syn-" then he referenced sam and i had to pause the video and sweep for bugs again.

[@thiagoennes]

LOL , i like both channels for VERY different reasons

[@TechGorilla1987]

@9:51 - RE silicone heating mats - back when I was an electrician, we used a series of Greenly silicone heating mats to soften and bend plastic conduit for service installation. Mid 90's probably.

[@pyroman590]

I loved the "look mum no computer" reference! I about spit out my coffee!

[@bigben747400]

I really missed that humor, been quite a while but the wait was well worth it. By the way: (Excuse me if you already know that) Last open door day at the PTB they were calibrating instruments for free. Still got contacts there, so just reply if you are interested and i´ll try to find out for you, if they´ll do it again next open door day. Then again you do´nt seem to have any problems getting the job done yourself :-)

[@tomkzinti2760]

I actually took the time today to put a Like on every one of your videos, because they are WORTH IT. You put out very very decent videos filled with entertainment and factual, professional work that is both interesting and accurate. Good on ya, mate. Here's a few ppm's for your effort. . . . . . . . . . . .

[@satansoft]

Your genius videos teach me a lot about electronics and humility ! As both qualified master electronic technician and master electrician your knowledge exceeds mine by far.

[@yt4krist0f]

Nowadays I enjoy to watch such content for 30 minutes much more than any TV series... :-)

[@greg4367]

Technically fascinating, hysterically funny. Bravo my friend.

[@NS-no1li]

Thank you for my daily dose of German humour and test instrument repair and rework.. Always good

[@edgeeffect]

I just bodge up microcontroller circuits on stripboard.... so it's such a delight to watch an artist at work like this.

[@zxborg9681]

Super interesting, both the old Fluke and your DIY implementation. Love videos like this!

[@Ratkill]

I come for the information but stay for the humor and editing. Top tier stuff.

[@LetsPlayKeldeo]

I dont unddrstand about 98% what you talking about but I could watch you solder and repair stuff every day all day long

[@Slartibartfas042]

I literally love that kind of humour! 😆 Great job done and this videos are worth to be watched even after years! Keep on and BIG THANKS, Marco

[@albinomonki]

I would love to see a video about your data collection setup and work flow. Very interested in grafana, and would enjoy seeing how you capture and curate all your data points.

[@milomitchener4166]

3:12 you just earned my subscription lol. love to see some safe and legal thrills

[@esunayg]

i dont understand and keep up with the things you mentioned (around 15% understood) but loving to watch till the end. soo dense and informative! and also fun! thanks for your great videos

[@pistolgamer4]

He's back

[@georgeashmore9420]

I wish I understood more of this but it's so interesting to see such high precision engineering

[@codingmarco]

Yes, the 3458A self cal would be an interesting topic for a video! I also noticed these (very small) jumps and it would be interesting to learn more about them :)

[@boltonky]

5 mins in and this reminds me of talking to my mate about engineering stuff...i get lots of it but eventually it goes over my head. I need more practice and cool machines to test on

[@michaelathens953]

I love the aesthetics of those old resistors, they remind me of the ones in my old guitar amps. They're just retro and funky and cool.

[@keanumack3944]

„Still hasn’t recovered from being assembled 7days ago“ killed me

[@wesleymays1931]

So that's why babies just cry all the time

[@lost4468yt]

6:28 those common Hakko CHP-170 cutters are just rebrands of Piergiacomi ones. Here in the UK the originals are significantly cheaper than the Hakko rebrands. Plus the originals have yellow handles instead, which looks much better.

[@NiHaoMike64]

I remember getting a pair only to find out it didn't even last as long as a Harbor Freight special! Definitely a fake...

[@lost4468yt]

@@NiHaoMike64 what do you mean fake? Piergiacomi are the actual manufacturers... They just make a red version for Hakko. Hakko do not manufacture them.

[@NiHaoMike64]

@@lost4468yt A counterfeit product that claims to be that brand but really isn't. A lot of the time, such fakes are far lower in quality than the real thing.

[@lost4468yt]

@@NiHaoMike64 oh I thought you were saying that Piergiacomi aren't legitimate, when they absolutely are. Also what happened to them? I don't think there are counterfeit ones out there, as the product is not expensive and has a rather unique production, I would doubt there are any counterfeits of them. Maybe you just had a bad pair? Also I assume you know that you can't cut stronger metals or thick things with them? They (and the Hakko version, and just this type of cutter in general) will easily get damaged from doing that.

[@NiHaoMike64]

@@lost4468yt As I recall, they dulled very quickly cutting some pieces of CAT3 cable. I then found that it took next to no effort to sharpen them again with a file but they wouldn't stay sharp for long, indicating the tips were not properly hardened.

[@Sherwin657]

I have no idea what's going on but I like watching you build stuff

[@eamondo2]

The man, the legend, has returned!

[@frosty129]

Thumbs up before I watch, but Marco please post more often. Quantity over quality. Everything you do is interesting.

[@pitushi]

Reps Precision Group !!!

[@rachmatriyanto7057]

maybe RPG-1000 its great product name

[@BogdanO45]

Great to see you posting again. Witty, funny and informative as usual.

[@ryanmalin]

Thanks for explaining leakage current across "isolation" transformers.

[@Anvilshock]

> "10-V source" > "9V+AA" Oh God no

[@wesleymays1931]

I mean... who cares if you're off by 5%

[@666Tomato666]

@@wesleymays1931 oh, you just need to slightly discharge the AAA and you're golden!

[@someone8944]

@@666Tomato666 ESR: no

[@PeetHobby]

31:45 If you shift the precision from the zener to resisters you can take the zener out completely and make it all resistor based, in that case the Zener is just a costly component that doesn't service it purpose anymore, I do I miss something?

[@jamiejoker118]

Way over my head of electronics but love watching your work

[@N1gel]

Great. Such a niech subject but so well thought through and executed and video produced perfectly. Thank you, well done.

[@AdityaMehendale]

Speaking of low-capacitance galvanic isolation (like the batteries you propose) - how much power does the circuitry consume, on average? I may have a very nice work-around for

[@reps]

at the moment I am trying to lower the power consumption as much as possible to reduce self heating.

[@AdityaMehendale]

@@reps A bit of both. Blue LEDs ~420nm act as excellent photo-collectors provided they are excited by wavelength matched violet LEDs or lasers (405nm). It is possible to get a photonic efficiency of up to 40% (!) and end-to-end efficiency (including the photonic efficiency of the LED of ~ 10%. In other words, you have a violet (visible, safe) "light source" consuming 10W of electrical input at one end and a Blue LED array outputting (ideally) 1W of electrical power (and unfortunately 1.5W of radiation-heat, ideally) at the far-end. www.researchgate.net/publication/273416580_All-optical_power_and_data_transfer_in_catheters_using_an_efficient_LED

[@reps]

@@AdityaMehendale Wow, fantastic info! Thank you for sharing. I vaguely remember seeing 20% being possible with optimal LEDs and modern solar panel (this might just be a theoretical value, not sure if anybody tried) but your method would be a lot cheaper and more compact. Love it!

[@AdityaMehendale]

@@repsA few nice things about the wavelengths: - The "royal blue" LEDs have an MPPT-voltage ~3V that is enough to power most MCUs without needing a dc/dc converter - As the photonic efficiency is 40%, you "only" need to dump 60% of the power as heat at the receiving end (so 1.5W/W instead of 4W/W as in a solar panel) - Not only can the violet power transmitter be modulated to send data forward, but also the blue "receiver" can be load-modulated to send data backwards (as demo'd in the video); the paper reports a few100kbps to be possible in the backwards direction without separate optics - veri smol (1mmx1mm) Tx and Rx for ~ 100mW (excluding space needed for collimators/fibers/etc) - 395-405nm violet lasers (no collimators needed!) are cheap and easy to find from blu-ray stuff - 430-450nm blue InGaN LEDs are commonly used in remote-phosphor lamps - Photo electro luminescence is frickin' cool (more info on this in the paper) It basically scratches every itch I had with galvanic isolation for oscilloscope-probes, bio-measurements, high-side gate-drivers, HV-stuff, contactless stuff, and more... Only 'issue' is the required line-of-sight (or fiber).

[@michaelhartley8426]

Missed your latest videos. No notifications from KZbin GRRRRRRR. Thank you. Be well.

[@jensknudsen4222]

Electrical engineer: The leakage current through these six layers of top grade insulation material is surely negligible. Metrologist: Can we talk about that for a minute?

[@schmetterling4477]

The metrologist wins this one hands down.

[@medienmond]

You could order a charging module for lithium ion batteries with integrated buck-boost-converter for your voltage reference from banggood or ebay. They are not really expensive and you would eliminate the voltage drop when the batteries got discharged. Some modules even include a lcd screen with measurement of voltage and amperage and the ability to set these values with direct visual feedback. Even the transfered energy while charging can be monitored. Let me know, if this "wink" in another direction has solved the ppm-drift of your device in the end. By the way, it does not matter what your videos are about. Regardless of them being about cnc, 3d-printing, electronics or harvesting fresh condensators with your dog; they all satisfy my initial expectation when viewing a new video from you. The sound of your voice and the very distinct presentation of the various topics is very relaxing and inspireing to me. Maybe you could update your viewers on the progress with your cnc machine since you build the machine. What are you fabricating the most and what else do you use it for? Greetings from Rhineland Palatine in Germany by some guy who is building a 3-D Printer you would have build nearly exactly in the same way.

[@InssiAjaton]

Sometime in the 1960's (I believe) Philips published a design brief about an ovenized reference voltage source that was built around two zener diodes. Or actually one avalance type (positive tempco) and one zener type (negative tempco). Additionally there were several resistors. In short their idea was based on utilizing an avalance type (higher voltage) diode as the pre-regulator and the lower voltage (zener) as the output stage. Besides selected nominal voltages, they trimmed the resistors to provide an optimal current and thereby a good compesation. I myself remember building a 10 V reference from a 1N825 temperature compensated zener that to my understanding consisted of one zener and two silicon diodes in in series inside an ordinary (DO-35?) package plus my added op-amp. I also at first made a mistake that prevented a start-up. Needed an additional bias resistor for correcting that.

[@NNNILabs]

"ship to my friends all over Europe" That one Indian guy: 😢

[@uditkotnis7531]

And the 45 degree oven temperature.

[@KaedennYT]

Edit: Disregard, found them in the description. -6:48-- what is that capacitance probe? Where can I find one and for how much? And do they measure inductors and resistors, or can I find probes for that?- -That probe would make finding seriously bad caps a hell of a lot quicker...-

[@bindkeys]

19:28 the numbers are visible in certain angles

[@tiemanowo]

10:54 This reference was priceless!

[@Max_Marz]

Wrapping that mu metal can with the heater was so satisfying, goodness.

[@denisschneider5642]

I work at an spectroemter company. We actually use these red heating stripes to heat our optics :)

[@bansci]

What do you think about using aluminium PCBs to keep temperatures homogenous? (I just saw jlcpcb are doing them). Using flex PCBs to reduce stress is ingenious, is this something measured/studied? Stress distributions in flexible inhomogeneous composite materials is not straightforward, at least with FR4 you know it's going to dominate the behaviour, but with flex PCBs the traces are as stiff as the support (I guess), so you could get something weird or unexpectedly high stress

[@reps]

yes, that JLC price is incredible, I hope it lasts a little longer so that I can come up with some cool project for it ... the whole PCB thermal expansion vs. precision resistor story is a bit pseudo-sciency admittedly. there is a vishay paper stating that only thick film resistors are affected and that solder joints are the worst offenders. but I liked the idea too much to listen to these reasonable sources :)

[@dtiydr]

6:14 That board had rev B, you had rev E where what ever they did one thing was to not have those resistors close to the board but quite a bit away as it should.

[@lmamakos]

I must drop everything to watch this latest PPM hunt!

[@jessewigfield9704]

Just an amazing video!!!! I can’t wait to make my own hermetic reference. Thank you so much Marco.

[@craxd1]

You think the foam insulation is something in this? Try working on an old Guildline from Canada that used a vacuum flask to house the ovenized zener. They had the silvered glass flask mounted in a foam insulation as well. I was lucky enough to obtain one of those to see how it worked. It had a dead non-standard battery.

[@TNW1337]

I would only trust High end lead acids for up to 3 years max, in any mission critical devices. 5 Years if it is not important. I used to see them Dead just after 2 years as a fire alarm inspector. Even the best brands had battery's die after 3 years. I am surprised you do not have a high end lead acid battery tester. BTW love the videos.

[@roboman2444]

32:40 did he really just blur censor out his calibration trimmers?

[@nickstanley5064]

I think those are plastic plugs to cover the cal trimmers holes.

[@JohnGodwin777]

Blurred what seem to be some stickers on there as well

[@roboman2444]

@@nickstanley5064 When the wire moves in front of the hole, the wire gets blurred too.

[@Rizko505]

Those are naughty holes, they could tempt less accuracy 😏

[@Betterstartnow]

Pilgrimage and on-site camping...love it!

[@annelisemeier283]

The Saddam under your DIY reference had me dying

[@joshmaresch811]

You speak such amazing English for a German. I just like listening to your voice sometimes.

[@excitedbox5705]

Using ceramic insulation would give you more stable temps because of the low thermal transfer. You can use brazing to hermetically seal those feet and it will draw solder in. Just use plenty of solder paste around the side of the feet and stick in the hole. Heat the housing and paste and as it cools it will draw in the solder as it hardens.

[@johnwest7993]

18.6 volts is the industry standard voltage for chargers for 16 Volt lead-acid batteries. BTW, I've had the tour of the NIST lab that designed and built the Josephson Junction Voltage standards. (Also Time and Frequency and the F1 fountain clock.) For a tech guy into high precision it was like taking a trip to Mt. Olympus. Just damn. I was pleased with my Fluke 5.5 digit bench meter and my WWVB disciplined Xtal standard until that day. But I can never be happy again.

[@mnamnam6061]

Holy reflection, what ... , ahm let me ...., I mean ...., yeah was quite a bit of Information. There might be some extended heat in my sealed enclosure too, the one up top the shoulders. To cool down I gonna repair my newly aquired Stelltrenntrafo from anno dunnemals (some long time in the past), enjoying % with doubledigits. Echt Klasse was du da jedes Mal raushaust.

[@cdh79]

9:57 plus 2 mV per Kelvin, but the drawing shows +2 mV/C? what's right, Celsius or Kelvin ?

[@mbart]

Any idea about the 3 resistors (6,2M, 5,1M, 2,4M) to the right at 12:27? These seem to be rather useless, but maybe serve some purpose?

[@mlab3051]

I love high engineering detail video like this. It's good for my engineering mind.

[@andrecarlos985]

Marco I hope you are right, with all the floods going on. Keep safe

[@theovannieuwenhuizen5756]

Thank you so much for yet an entertaining and informative video. I love your strive for excellence.

[@anthonyjobson]

LMAO! That foam to cake transition had me!!

[@xani666]

What's that "creative application" at 14:56 and why it is frozen ?

[@shantk7378]

I absolutely love this.

[@fullwaverecked]

Man, my seance of humor is no laughing matter as well. Good on you. Cheers from Utah!

[@stcoso]

Many of those Schaffner Input filters are also filled with RIFA capacitors.

[@windward2818]

Perhaps redesign for an SMT only approach (TH part leads bent to solder smt) using thin 2 layer flex PCB on aluminum (attached after soldering) designed to offset and make heat sources consistant per area, a sort of heat gradient proof approach.

[@Vykyification]

I just love this channel so much!

[@loligesgame]

32:30 why are the calibration holes censored?

[@JoeSmith-cy9wj]

I realize this video is from a year ago, and I have no where near the experience you have. But in trying to minimize noise, have you considered the mains circuitry? In America, we usually have a step down transformer supplying 2 - 120V ,180° out of phase lines to the fuse panel. This is derived from a single phase high voltage line on the light pole. I would imagine noise between the two phases in the house might cancel if you device transformer utilized a winding connected to each side of the panel. I haven't investigated the situation in Germany.

[@DrFrank-xj9bc]

Hello Marco, the drift of your DIY LTZ1000 reference ( 1ppm/day?) is way too high. Provided a proper circuit, components, handling during soldering and a correct thermal regulation, it should always drift < -2ppm/year in the beginning, and after maybe 3 months, about -0.8ppm/year thereafter, disregarding any assumed "burn-in" effects, sample variation and such. Your preliminary burn-in process of the LTZ, I'm suspicious about, please explain how you have done it. The cleaning process with DCM might have severely damaged the precision resistors, as these are not hermetic packages. Cooling the LTZ below -15°C might damage it, regarding stability. I hope you didn't assemble that frosted one into your flex foil assembly. Your oven temperature of 60°C might be too low, especially regarding that exaggerated thermal insulation. I suppose that the oven control still does not operate properly, and might be the root cause of your observed drift. First, you always need to have some heat flow out of the whole package for stable regulation, and 2nd you need to calculate the temperature rises by self heating, i.e. room temperature plus insulation T-rise (~10°C) plus shield-package self-heating (+5°C) plus self heating of the LTZ1000 (+5°) or 'A (+10°C) plus regulation overhead (+5°C). At these high temperatures in your mans cave, (exceeding 30°C, probably?) you need at least 65..70°C, I'd guess. You should also try to characterize the basic LTZ circuit first, and then the 7=>10V circuit separately, to identify the fault. @31:00 you have misunderstood branadics statements about these 0.01ppm/°C.. that's always achieved with an ovenized reference! The T.C. of the non-ovenized LTZ (and the reference described in this thread) can be trimmed down to a bit less than 5ppm/K (instead of the usual +50ppm/K of the LTZ standard circuit), but not such small values than to omit the oven regulation afterwards! It would be good, if you would join the eevblog thread, or the volt-nuts community, that such traps could be discussed upfront, and in a more convenient manner. Before you start other references, maybe you want to fix your LTZ reference first. And what about the high noise of one the FX-boards?

[@lancelink88]

Please more Fluke gear, I love it!!!

[@reps]

same tbh

[@stefanhuebner5358]

What usually creeps out of those Schaffner mains filters are the internal RIFA metal paper capacitors

[@johnwilliamson467]

Your comment are great. Simple glorious . It has been a very long time since I have LOL this much BRAVO.

[@peterfitzpatrick7032]

I particularly liked the part where you mentioned ppms.... 🙂 And its always nice to de-stress after a particularly challenging project by playing with some playdough... The "re-cycling" watersplash & mention of eels was nice.... I'm assuming they were electric eels ? 🤔 From the Emerald Isle 😎👍☘️🍺