The ratio of how much I enjoy this vs how much I understand is off the charts

You definitely need to try black magic. I mean microwave stuff, that would be extremely interesting.

I would love to see you do some RF stuff, it contains even more magic than nanovolts. Plus you often play with nanovolts, disguised as dB.

Does anyone else watch these videos and have zero clue what he's talking about, but is still fascinated...

Noticed the roll of paper towels, handy for mopping up escaping PPM's......but luckily Mr. Reps didn't need many, he caged them back up safely.

this guys sense of humor makes every vid a 10

Thanks a lot for this "wetting current" hint. This might be the problem why those super expensive hermetically sealed relays on the voltage sense card (ADC) in the semiconductor test stations I'm going to work on are failing... "even there is literally no current flowing through them"... :)

*Overview* - Marco Reps discusses the Datron Wavetek 4950, a multi-function transfer standard, detailing its issues, repairs, and tests. *Repairs and Issues* - Fixed a missing positive voltage supply rail on the analog board. - Replaced a damaged op-amp in the AC millivolt pre-pre-amp. - Addressed leakage current issues in the current assembly. - Replaced the original front input connector with a more universal one. - Replaced a worn-out relay affecting the AC attenuator and preamp board. *Modifications* - Created a new sheet metal holder for the front input connector. - Used PTFE heat shrink tubing to add dielectric strength. *Calibration and Testing* - Used a Python script to calibrate the Datron Wavetek 4950 against a Fluke 5700 calibrator. - Found some discrepancies in ACV linearity. - Used thermal voltage converters to validate ACV linearity. *Additional Features and Observations* - Found that the Datron Wavetek 4950 has excellent DCV linearity and low noise. - The device uses hermetic bulk metal foil resistors for stability. *Conclusion* - Marco is impressed with the Datron Wavetek 4950's performance and is glad it was saved from being discarded. *Positive Points* 1. *Excellent DCV Linearity:* The Datron Wavetek 4950 shows remarkable DCV linearity, exceeding expectations for a seven-and-a-half-digit class device. 2. *Low Noise:* The device has low noise performance, even down to the least significant digit. 3. *Stability:* Uses hermetic bulk metal foil resistors for stability, making it reliable for its primary function as a multi-function transfer standard. 4. *Versatility:* The device can be modified to act like a normal multimeter, adding to its utility. 5. *Durability:* Built with quality components that guarantee long-term stability. 6. *No Cooling Fan:* Lacks a cooling fan, which is seen as a positive due to the longer time constant and low temperature coefficient. *Negative Points* 1. *ACV Linearity Issues:* Some discrepancies were found in the AC Voltage linearity during testing. 2. *Complex Repairs:* Multiple issues required attention, including replacing worn-out relays and fixing leakage currents. 3. *Limited Documentation:* Lack of comprehensive service manual makes some advanced adjustments risky. 4. *Old Connectors:* The device uses older types of connectors, requiring adapters or replacements for modern setups. 5. *Settling Time:* Thermal voltage converters used for testing have a long settling time, making the calibration process lengthy. These points are sorted by their impact on the device's performance and usability.

I have no clue on what all this stuff is for, but i love your dry German humor and your technical explanation and your curiosity and that you like me take everything apart to see what makes it tick... My big question is what do you actually use all this equipment for? I know what ppm and a lot of the technical terms since i am en electritian and a ventilation technician, but still a lot of this stuff is way over my head 😀

Check out Raymark labelling material for front panels. It’s a kind of polyester like backing with an uncured epoxy coating. It comes in label or A4 uncut sheets. You print on it with an inkjet and then bake it in an oven. The baked sheets are resistant to oils, solvents, fuels and quite wear resistant!

I still can’t believe your sense of humor in not your mother tongue. Love it!

Pretty impressive equipment indeed, Marco! 😃 Fantastic work fixing it! Stay safe there with your family! 🖖😊

I love this content. I have a feeling that given an ossified claw from a T-Rex you could make it walk and talk and feed on small children like back in the good old days. Thank you for this work, and for sharing it.

Very nice Marco

PVDF heatshrink + PVDF cables (SPEC-44/MIL-W-81044) make a very good pairing. The heat shrink fuses with the cable jacket and forms a perfect bond when using the right temperature, giving you up to 2,5kV voltage rating, as well as all the excellent properties associated with PVDF. Just unfortunate that the HV type can get very pricy per meter, but the 600V rated one is decently priced.

Excellent repair and modifications. Always wonderful to see a fine instrument given another lease on life. Also, that's a lovely $1700 torque gauge you have there! No resentment from me, but I see way too many awesome looking tools made from unaffordium on KZfaq.

A marco reps upload. Exciting

“Lay the Re” 😂 Good one.

I might have something for you that has (theoretically) "surprisingly good linearity" as well...once I fix the 1mVpp noise in the conversions💀

I remember you as a child - you designed JBC clone soldering iron - that was cute

I have to say I am jealous on you, to have the ability to dive so deep and sort things out. I have been fighting for more than a year to fix my oscillator in my Fluke 5100B without success. Thanks for a great video. Happy new year 🎆

At 16:47 the towel of the Physikalisch-Technische Bundesanstalt (PTB) Braunschweig is very pleasant 😂😊

didn't know PCBway did sheet metal fab, going to try this out!

21:37 - Sir, you are the real treasure in my mind. 👍

You are More than just GOOD!👍👍👍

ThX for a great vid with so much acquired knowledge and effort.

شكرا على الفيديو

I have no idea about 90% things you talk about. But I love this channel anyways! :)

Another awesome video, thank you. 👍😉

Yes, finally. Fame at last. Fluke Norwich is my workplace. We have many treasures indeed, including most of the guys who were there in the Datron days. More than that, I'm not permitted to say.....

Do GHz next Marco! 😂 Norwich is pronounced locally as Norrij with hard J sound x

Pentaherz ;) Thanks for great videos as usual ;)

20:14 is like watching marco do some secret Voltnut ritual

16:50 The gender-fluid 874 connector you speak of was created by General Radio, not General Electric. A tiny typo. Another fantastic video. Thank you!

Congrats! You could make a video on precision scales.

Wouldn't mind seeing Atto-amp measurements. I've gotten noise down to ~30fA at 30Hz with a LMC662, a discrete high voltage output stage, and a 10Gohm resistor array. (about $100 in parts) Stray capacitance to the shield from the 10Gohm resistor caused fun times. Had to get cheeky with driven shields to solve that problem. The circuit made a very useful amplifier for photo-diodes. Would full-scale with micro-watt laser beams so you could do great measurements with poor laser setups.

Very neat.

How about using cadmium copper instead of pure copper? It is stronger and more wear resistant, with pretty good… ooh, right, RoHS… OK, not even mentioning beryllium copper then.

Damn, You insane! Me like it!

With this guy I don't even need to be reminded to like and subscribe. I just wait for him to crack a joke and I am bought. Lay the ree... wow... I know my like will be safe with you, sir.

GHz! Would love to see that SA you have hiding in the todo list :)

Next? Maybe you'd like to use the Swerlein algorithm on your 3458A, for measuring AC @ < 10ppm uncertainty up to 1kHz.

cool stuff! I don't know much about 'electric metrology' but I know physical word accuracy, its cool to see and you make it seem approachable. Random ? but did you once have a video on some sort of distance sensor, which also had visible light camera as well? I distinctly remember a color map overlay of the video input, with distances called out (I think it was red close - blue far?). I'm almost positive that is the video that I found your channel with, but I can't seem to find it... Maybe I'm confusing it with all your thermal awesomeness... Thanks for sharing!

yes

Those old GE connectors are quite hard to find! I replaced them with N-Type ones on my pulse generator, because I couldn't find suitable mates or cables I'd actually trust for sub-nanosecond rise times.

I spy an expensive 3.5 mm (or 2.92?) VNA test cable in the upper right corner around 12:00 ... Exciting to see what the future has in store...

I had no idea Datron used to be an electronic sensors company lol. They have an interesting story.

Could you go into more detail on the construction of your Fluke-inspired test-leads?

If you Still need an opa637. I have some in SOIC and I think at least one in the OPA637SM (metal can) happy to send your way for free if you like. Most of my work these days is multichannel audio and they are not of any use as a low noise error amp in a low noise regulator really, due to poor stability at low gains.

Have you considered dumping all data from the eeproms and such so that you could revert it to the current calibration and then doing the AC-lin calibration? Having dumped memory means you can revert it to pre-cal state if it fails

I keep my wife faaarrr away from my eBay account for that exact reason 😅. Well, that and my server acquisition syndrome as well. 11:38 The Al business card came out really well! Surely it would be no worse at 1.42kV than the mounting bracket anyway? Unless the holes were smaller in the cover plate?

after going through the pain of adding PTFE shrink-tubing to the input connectors, wouldn't the metal plate around them also cause a shorter air gap with those fork terminals ?

You have more LPM's (Laughs per Minute) than Seinfeld 😂😊

please test the new ts1c cordless soldering iron from miniware!

I wanna see ghz stuff. specifically, somewhere from 70 to 90 ghz. plus some liquid nitrogen. that would definitely help elevate your voltnut obsession to the next level.

About the glitterbox... I do have to motivate someone to let me adopt something....

Nice equipment! If I may ask.. do you have a particular need for all these ppms and digits? Or do you mostly use your equipment for measuring your other equipment? Just wondering!

mannnnn make something easy and fun in ur style !!!!!

I would like to see some nH.

I would have slotted out the damaged PCB area completely and used point-to-point wiring. Old Fluke stuff has it all over the place in the most sensitive circuitry. Did PTB give you that towel?

What's the end goal of all these ppm/ppbs ? Any practical applications ?

I say Josephson Junctions. Per Wikipedia those are also how the Volt is defined!

The AC’ness 😂

TI are suprisingly good to but parts from directly. $23.017 for the OPA637.

How to enable so it will measure full range and not only around the cardinal points?

10:09 Cold solder joint in the transistor leg in the middle of screen ?🤔

What would be a substitute for copper metal if I don't want the oxidized connection points?

The story continues…

Wait, can an input relay go totally bad as in always open from not being used or is it just a bit of extra resistance? IE can relay contacts go bad enough just from sitting to cause zero readings on a DMM but still pass internal calibration?

Im not surprised this showed up when i search asmr

Watching this makes me wonder over the years how much that diagnostic function would be used. My guess is that the amount of hours of labor it takes to figure problems out means it's always going to be more cost effective to replace units. It sounds like you put several weeks of time in working on this and still kept running into new problems. It's not that I don't think corporations main motivator isn't greed, it's just that it's largely impractical to repair complex electronics.

Awesome! Now do something with microwaves or even better,... generate x-rays or so!

😱😱😱😱😱😱😱

I sense some voltnut moistness

AR488... GPIB to JSON adaptor

Do you review 5.12Kwh, and 11.8Kwh battery?

you Rocco Siffredy of electronics, you...

24:06 almost choked laughing.

I need a girlfriend... I mean watching KZfaq at 5.30 am... she would keep me in bed until a reasonable hour. Your videos are so good, they take precedence over all sorts of things......

Have you ever shown that 40 GHz network analyzer in a video? 🤔

Yummmmm yumm ppms

Did you renew your KitKat club membership ?

The time is not long gone when measuring devices with 1% accuracy were considered sufficient.

do RF

Femtoseconds please. GHz is pedestrian.

Marco, du hast eindeutig zu viel Geld übrig 😀

Did you mean General Radio 874?

Femtoseconds please ⌚

Was machst du eigentlich hauptberuflich?

RS PRO function generator ?? 🙈

gHz plz

arf arf

I guess this means you have to take both asterisks off your old thumbnail now

Rindfleischetikettierungsüberwachungsaufgabenübertragunsgesetz

fs femto time

AH yes... carbonized pcb material. I still fondly remember digging out burned conductive material from a few macbook motherboards with a blade, drill bit, or tweezers. Fill with expoxy and rebuild the traces over it. It's like cancer, I've seen it travel horizontally through the board as things get spicy.

Whats next? Beard-seconds!

Moar CNC bitte

Try Microwave.

rep rep