Super glad you've repaired it !! Marco Reps: Look after his name, as he is destined for greatness !!

21:00 No wonder it failed at that point, you mounted it on its side. This causes all the electrons to fall to the bottom of the hybrid chip and floods the ADC.

"It just means some non-volatile memory was not even able to do its one job in life: remembering stuff." - Oh god my sides.

It's real stuff, very informative, educational, and interesting with a burst of small humors. We just can't help inadvertently watching till the end every time. ❤

We had a saying at Keithley back in the late 80's and early 90's..."Nobody ever got fired for buying HP". We had a Josephson Junction standard and we monitored it with a 3458A. Incredible piece of engineering.

16 minutes in and I've convinced myself I won't be looking for or trying to buy one of these. The pic of Rossmann holding a sign was the icing on the cake :-)

23:00 that ESD clamp must hurt, quite the dedication.

Thank you for the nostalgic tour! After an 18 year hiatus from Agilent, I sell EDA software for Keysight today...started with Hewlett-Packard in 1988 just out of EE university. Met Bill Hewlett and Dave Packard not too long before I visited Loveland Division on training tour. It is an incredible privilege to represent and sell products that thousands of HP/Agilent/Keysight geniuses have designed. These are products that design and test the technology that most people take for granted. Many of the largest customers today still use HP test gear that is 30+ years old! what lasting value. amazing. thank you Marco for this review of the HP 3458!

As student of electronic engineering a love these types of videos. I also own the HP3458A. I bought it for 1,000 bucks from a company that went bankrupt.

The first production 3458a's were offered for sale in 1988, but our lab first started using early prototype test units around 1986 -ish.. If you own a 3458a, get the annual insurance policy from Keysight, and it won't cost nearly as much to keep the unit in good repair. It is a good value.

No one else could make the explanation of a 33 year old circuit more captivating. Thanks, those Loveland engineers sure we're a crafty bunch.

After the intro, I kept wondering what would compel somebody to give away such a piece of history. The next 25 minutes was all the answer I needed.

8:12 "No Quirks and Features will be left out" - Is this the Doug Demuro of precision instruments?

1 PPM per Month, that almost made me choke. And a cal every 1°C, now that's presision.

45 minutes?! Thank you Marco for this amazing gift!

5:32 The good old days of HP Journal, back when they put enough info out for some brave people to actually try to reproduce their magic. I'm submitting my engineering thesis tomorrow and it's basically my approach to constructing the TDC described in the April 1986 HP Journal, just modernized a bit and done without any custom IC magic (just some BFR93A's and BTF93's).

I was having a rough week and thought, "man, a Marco Reps or This Old Tony video would be really nice." It was. Thanks for coming through for me, buddy.

That is an... _interesting_ and painful looking way of grounding yourself. Beautiful machines, I've been coveting them for years.

I used to live a mile away from the HP plant. Once a year they would have these open door events with pallets full of old stuff. For a budding electronics nerd such as myself this was heaven on a pallet! I'd spend $30 and came away with 200 pounds of stuff. I still have a few peltier cooler I got from HP.

The binding post are special low thermal emf type. Made out of tellurium copper or beryllium copper. Sometimes directly gold plated with no adhesion layer such as nickel or chromium.

As someone who troubleshoots complex systems for a living, this kind of work is inspiring! Marco is a beast

Can't even imagine how long it took to film, edit, script and narrate this... Oh, also the repairs themselves. Thank you!

Thank you for taking the time to make your videos. Informative and entertaining as always. I rebuilt a 3456a recently. Build quality of the old HP equipment is superb.

That's an excellent ground strap you've got there at 23:33!

I have no idea what's going on but can tell clearly that I'm witnessing greatness

Oh boy, the voice, the technical talk, oh boy, so damn good. And I'm just couple of minutes in, cheers Marco

Wow, this is the first time I've watched your channel and I already love it! Halfway through I said out loud "how can they add all this complexity and not destroy the signal they are trying to measure"? And the humor, totally spot on! Off to watch more vids...

Just found this channel and I'm hooked! Informative, visually entertaining, and the brilliant sense of humor is an absolutely fabulous combination. ETA: Even your beverage selection is delightful. Bravo, sir!

That ADC.... They basically made calculus happen in their board, guys are brilliant

Outstanding video Marco, your whit and comments add to the extreme complexity of your videos. Louis

Hair clippers @ 20'51'' is brilliant. Thanks for another great video :)

Truly stunning work. Congratulations on the fix.

Your videos are so technically absorbing, and your switchblade thru the heart humour is to die for. Cheers!

Your workshop and equipment drive me crazy ! What a wonderfull place with absolutely lovely devices... ! I love it !

Fantastic video. I keep dipping back into your archive as there is so much to take on, its impossible to catch it all on the first view.

Regardless of length or complexity I'm hopelessly addicted to your video! Thank you :)

What an outstanding video Marko, love your cometary style, you are fast approaching HP greatness!! Louis

I could watch your work all day, why did it have to end ! great stuff...cheers.

👏👏👏👏 The animations you've included are brilliant! Absolutely fantastic work as always!

Jeez you have always been the most engaging electronic engineer on earth. Glad the channel is going well. Thankyou for showing me the cool stuff and explaining it all.

with every new video I see , I am extremely impressed with your skill set and abilities.

My dad worked on the 3458, as did one of my coworkers. They really threw everything they could into the design. I've always liked working on the HP designs from this era as they silkscreen around functional blocks to help us work on them.

I love these new types of extremely nerdy videos you're posting! I don't understand anything! It's a thrilling ride!

Congrats! Always great to get an awesome reward at the end of the long road!

Nice work Marco. Your videos/projects are a treat to witness.

Great to watch, we have a trusty Datron 1271 for nearly 20 years and it is used for automated cal of production tools. Every year it gets shipped for Cal I get a bit more nervous and need a backup so am planning to pick up a 3458A as it is compatible.

We have a bunch of these at the calibration lab I work at, and was one of the first instruments that got me interested in precision. One unique use can be found in the Fluke 5520 service manual, where it measures some of the simulated capacitance with a 5700 and a 3458A using its sweep mode, since the frequency response is too low for an LCR to measure. Talk about overkill.

I just received 3 separate emails asking about 3458A purchasing advice. Here's all I know in a TL;DR: The prices, even for used and untested meters, are very high at the moment. No internal self test or ACAL can guarantee a good ADC, sometimes they start drifting slowly a few months before they finally start giving convergence errors. If possible you have to power on the meter and have it measure a trustworthy DCV standard for a week. Or test it per Service Note 18A: literature.cdn.keysight.com/litweb/pdf/3458A-18A.pdf Nobody seems to know what exactly causes these problems or how to cure them. In the grand scheme of things the dreaded U180 problems are rather rare. Because there are probably hundreds of thousands of these multimeters in use in the industry and in cal labs all around the world. The number of bad U180 cases is small in comparison: A few forum posts, youtube videos here and there ... On the other hand buying a used meter has increased chances of getting a bad one, because of course people will try to get rid of them after learning about the repair costs. Probably the safest way to go is buying from a company that specializes in used test equipment and is willing to offer a guarantee. i.e. www.ab-precision.de/ in Germany might be a good source. Good luck!

Impressive video, and impressive repair! Thank you for producing such an excellent video about such an excellent meter. I am fortunate enough to have been given a 3457A as a gift from my Dad. It's not quite as powerful as its younger brother the 3458, it's still an amazingly capable meter to have on the bench! I'm glad you got your 3458 working properly. I hate the thought of such a meter being tossed into the e-waste bin.

So happy for discovering this new channel!

impressive hardware and rework 👍 Thanks for sharing your experience with all of us 👍😀

I may not understand your passion for PPMs, but I certainly enjoy watching you chase them.

Well worth every moment of wait for this one. Keep up the good work.

These sens of bonedry humor and this deep diving in electronics .. I just love it! #allmightyBiegelehre

Awesome repair! I have wanted one of those for the lab for a while. Great Video as well!

I am definitely one of those two and a half. I Love the logic explanation! Please Keep this trend! I learn more from you than just about anywhere else!

That was freaking incredible. Incredible and damn hilarious. The fact that Marco went into “I ’m just gonna change every cheap component” was particularly honest and appreciated. Why is it I can never get anything complicated fixed??? Spectacular. I might have thrown away an immeasurable chunk of my life, but it had some real pleasure to it . . .

Excellent video! Really lovely to see this working again. If you're looking for higher vertical resolution measurement on the cheap, for future analysis, take a look at some of the Red Pitaya kits. Their 14-bit options start at under 300€ for a 2-channel 60MHz option, and they double up as a transmitting SDR (2x recv, 2x transmit). The software for them is open source, too!

Astonishing instrument, beautiful work.

Your videos are always a treat, glad to see you finally get to the promised land of metrology

Been waiting for you to step into this world as it is a world standard piece. You have fabulous gear and excellent taste in instrumentation. Can’t go wrong with your choices. Looking forward to more fun in the Marco Reps World. Stay safe my mates!😊👍🏻😷

your video is always inspire me to keep on pushing even those things are tough

Excellent. I loved this latest video. Thank you sharing your fun with us. 🤗

Very amusing Sir. Like your dry wit. Most interesting from a technical perspective also. I have designed several dual-slope ADC's over the years - first one about 1975 using an LM741 & LM311 believe it or not. Worked jolly well.

What a joy to watch! What an amazing masterpiece of engineering

Awesome video and epic repair, was wondering how long before you got one, entertaining and educational! Still going through a slow restoration my HP 3458A, thankfully mine just had a faulty outguard power supply, still needs to have some capacitors replaced, the non-volatile memory has gone senile and cleaning oxidised frame from a blown Schafner someone never cleaned up. Unfortunately my 7081 has died this week, looking like 5V power issues, hopefully nothing else.

I love this guys' delivery. Even I could get excited by a multimeter.

I calibrate a lot of 3458A's and it's really cool to see this type of work because we don't do any component level repair.

You have no idea how excited I got when I saw a 45 minute Marco Reps video in my feed

This video deserves to be liked much more than one time. Alas, youtube restricts it to once per customer. What astounding troubleshooting. Thank you for making these videos.

Great Video, as so very often on your channel! And wonderful instrument, you repaired...

I actually loved the simulation section, it's interesting to see how they parallelised the analog to digital conversion by basically splitting the input

I love your voice and how you roll off the final worrrrrd. Sounds very cool.

Ihre Videos sind immer das Highlight des Tages! Vielen Dank und weiter so!

this device is worth a fortune! you have some generous subscribers! Congratulations

I'm impressed.. good work. And so good to see Louis Rossman in your video (right to repair) 15:02 Thank you for sharing ..

This was excellent. Thank you from Colorado.

This is the best meter review I have ever seen.

Great video! It reminds me my times in the seventies in a calibration and repair lab. But by then, the HP equipments were stil from the previous generations. Nevertheless, I have learned a lot reading the theory of operation and understanding all the schematics especially when there was a malfunctioning.

I like how the steering hybrid is one of the few things keeping you from making one of these from scratch

Excellent video and it is good that you have included an important step omitted by most other videos. They all clean the instrument but most forget to sanitize the operator with an ethanol solution. Since dirty operators often contribute to the problem it is best to clean them before, during, and after repair and/or calibration. Good luck with your videos.

An excellent video as always, thank you!

THX Marco for those long videos!

Macroreps 45minute video full of his relaxing voice. This is gold in itself.

I spent time with a 3458A on my bench for a few years in the 90s. It was a sublime piece of gear back then when new.

Hi Marco, Thank you for such a fantastic video! That was incredible! Cheers, Mark

You know what amazes me about your channel? It's that you could pull of 50k views in just two days. Well done mate

baking soda and super glue make a great plastic filler and can be filed into shape. I even replaced snap clamps on plastic cases and the hinge peg on my cars visor mirror cover. You can brush on or dip the part in super glue and sprinkle on baking soda, repeat until you build up the missing plastic, then file or sand to shape.

nice and relaxing video, it helps me focus

Celebration time, another great video. Full stop and coffee time 🎉

ACAL was the Anchorage Center for Alternative Lifestyles up here in Anchorage, Alaska -- where much probing, measuring, and temperature increases occurred. It really put the "PP" into PPM

Fascinating video. Thank you!!!

I see vacuum stuff in the background!!!!! Can't wait for the vacuum series :D

Thanks for sharing! Excellent work and video

Great work! Thanks so much for sharing. ;)

Incredible effort

Thanks for the fantastic video! Your sense of humor and methodical attention to detail have earned you a sub from me. This is the first time I've come across your channel, so forgive me if someone has brought this up since this video was posted, but I have to wonder if the mains filter was killed by the film capacitors, rather than the other way around. Those film caps look for all the world like RIFA caps, which have a bad reputation for failing short with age and shorting the mains input, which I imagine that sealed mains filter would not be too happy about. You may want to consider putting RIFA caps on your replace-at-first-sight list, if they're not already.

My favourite multimeter was the Avometer. Starting as a technician in the 70's, I still remember told to measure the current on the main circuit as an introduction to the to always having your brain engaged.

What a beast of a video. Good job.

That was hilarious, entertaining, and educational. Thanks so much for making this video