Why do they call it a video amplifier? What has video to do with pulse counting? Am I missing a meaning of the word video?

@milantrcka121

9 ай бұрын

Old term from the times when baseband (including video) signals required an amplifier from "DC to light" frequency and linear phase response, i.e. radar. Signal conditioning and "squaring" happens in the counter mainframe.

@CuriousMarc

9 ай бұрын

It is a very misleading and confusing naming indeed. It’s historical. In radios, there used to be audio amplifiers that would go from near DC to a couple 10s of kHz, and IF and RF amplifiers that would operate at much higher radio frequencies, but in a very narrow bandwidth. Then video came along for TV, and suddenly you needed broadband amplifiers that would not only work up to the 10s of MHz range, but would also go all the way down to near DC. These were aptly called video amplifiers, by analogy to their audio amplifiers slower cousins. But they soon found other uses, and by assimilation, a “video amplifier” became the nickname for a sensitive broadband amplifier that worked from near DC to 10s or even 100s of MHz, even if it was not used for amplifying video signals at all. So here, video amplifier really means broadband pre-amplifier, and is used to improve the input sensitivity of the counter regardless of input frequency.

@bzuidgeest

9 ай бұрын

@@CuriousMarc tech is full of historical weirdness in many places. Thanks for explaining this particular one.

@StubbyPhillips

9 ай бұрын

@@CuriousMarc That's a really swell explanation! 🥸

"It's failing right there" *motions with entire hand*

@derkeksinator17

9 ай бұрын

Oh, I got a spectrum analyzer where that applies, never had so many faults in a single device, without something irreplaceable/expensive being broken.

In the 70's, Hewlett-Packard used to include the schematics for their *computers* in their manual set. H-P also used to make their own wire and cables at their Mountain View facility. They even braided the shields on their cables, extruded the vinyl jackets on the cables and labeled the cables with an ink wheel. There was a stellar craftsman named Mario Sarti that knew all about the equipment. HP even made their own keys for their keyboards then at their Santa Clara Division. The keys were made by two different colors of plastic (the letters weren't printed on the keys) so the letters would never wear off. Their boxes used to say "An Extra Measure of Quality" on them. That's before their Board of Directors hired bean counters for CEOs vs. engineers.

@c.ishikawa6346

9 ай бұрын

Digital Equipment Corporation, DEC, later absorbed into HP eventually after merger/acquisition also included schematics for their computers, minicomputers and their larger computers DEC10, and DEC20. One early hack of UNIX was to enable splitting of data/code space so that 16 bit DEC 11 minicomputer can store both data and code in 64 KB space each. But this was done by MODIFYING the CPU board circuit manually! Unless the hardware was modified, both code and data reside in the same 64KB space and that was quite tight. When I did a part-time job at an installation where DEC20 was available, I looked at the wire schematics of the DEC20 computer and wondered what can be done with the hardware. Folks at Stanford and CMU seemed to have done something special to run their patched version of TOPS10, and TOPS20 operating systems. Some features of these extensions were later incorporated into official DEC OS. I eagerly waited for the regular delivery of DEC User's Group magnetic tape on which these interesting software hacks were recorded. Those were the days.

@mudi2000a

9 ай бұрын

Even with consumer electronics it was quite common in the past that they are shipped with the schematics. I had a Philips CRT TV which I bought in the late 1990s and even that still came with schematics (which actually surprised me even then, I thought that stopped in the 80s). I never needed them because it didn't break. Not much later shipment of schematics completely disappeared.

It's always a treat to see the professional engineering inside of vintage HP equipment. They are sort of a functional work of art.

@CuriousMarc

9 ай бұрын

I am so agreeing with you. Engineering that good is art.

Desiccant MRE's, nice! Lets get it out on a tray.

The absolute wierdest thing, I'm on my terrace watching the video at 4:18 and the manufacturer of that dessicant... Culligan - there's a van for that company parked right outside, same logo and everything, god knows how many years later, evidently selling and servicing water coolers here in Spain. Mind blown.

@CuriousMarc

9 ай бұрын

We must both have gone through a wrinkle in space time. I can see no other sane explanation.

"it doesn't even say 'do not eat'! that's back when you were allowed to eat it!" (The desiccant) 🤣

Amazing! I somehow imagine who calibrated and packed that plugin, not knowing it would sit in that box for 60 years! Could you imagine buying some electronics today and discover the schematics in the box? :)

@PsRohrbaugh

9 ай бұрын

In fairness, many modern devices use custom designed chips rather than discrete components. Your schematic would show some input filtering, and your custom chip.

@onesandzeros

9 ай бұрын

That's exactly what I was thinking. Some dude named Herb, with a moustache and pork chop sideburns, starting his second pack of smokes for the day (it's 10 AM), approved this thing and packed it up. Decades later, here we are.

@zyeborm

9 ай бұрын

Ooooh, I'm going to do that now on the tiny things I make lol

I never knew I was interested in test equipment, let alone vintage HP test equipment, and here I am adding things to my watch list! Thanks, Marc! 😉

When you opened the box, I could actually "smell" it. It was always Christmas day when I opened a new HP or Tek instrument for the first time.

Classic Hewlett Packard was such an impressive company they could time travel spare parts into the future. 🙂 (It just pisses me off that the Hewlett Packard name has to be associated with the current HP or HPE).

Regarding Nuvistors: Braun used them in their radio tuner model CE-1000 to amplify the FM RF signal right out of the antenna in 1967. It was a one off, even the close follower model CE-1020 no longer had them.

@neilbarnes3557

9 ай бұрын

Also used as the first stage picture tube amplifier in Marconi MK7 4-tube TV cameras (and no doubt others) - very high input impedance and respectably low noise.

@krausdaniel49

9 ай бұрын

Musical Fidelity has now a days an audio amplifier range with these tubes. The Nu Vista range

@jean-pierredesoza2340

9 ай бұрын

@@krausdaniel49 Thanks, very interesting, I have followed this brand long ago, and am glad to see they are still innovating.

Marc gains 100 Out-Of-Box-Experience Points. He'll be able to enchant his oscilloscope now!

Oh how I miss the days equipment came with technical manuals whit circuit diagrams.

@user2C47

9 ай бұрын

I just worked on an air conditioner from about 20 years ago, and the circuit diagram inside made my life a lot easier. I wish they were included more often.

It is hard to tell which one is better, the equipment or its documentation. I have read some HP gear manuals just because the theory they include .... and they really take all the time to go in detail.

Wow, I finally understood some of this...the unboxing.

Damn, coincidental timing. I was a little behind on my CuriousMarc content, and this released while I was watching Part 4! No cliffhanger for me. 😃 Well, until I have to wait for Part 6...

When the HP name stood for something special........love it

Hi Marc, No HP 5245L collection would be complete without the HP 5260A Automatic Frequency Divider. 😃 I sure do hope we're going to see you bust out a HP 5260A and give it the CuriousMarc treatment. Thank you for showcasing HP test instruments.

Ive never come across a new noisy zener, I had no idea they could go like that with age, I will keep an eye out for that in future. I may well have missed that is some old gear that wasn't as sensitive. Always great informative videos.

@SeanBZA

9 ай бұрын

They do go noisy with age, depending exactly on any contamination during processing, that eventually causes surface leakage on the junction. That is why buried junction zeners are the preferred one for low noise, no way to contaminate the junction because somebody dropped a few skin flakes on the die dicing it, and then the carbon got baked on top of the junction during the sealing process. Regarding those capacitors any rubber seal tantalum capacitor will fail, the glass sealed ones very rarely fail, only with reverse bias, or gross over voltage applied and no current limit. Had plenty of the rubber seal ones fail as near open circuit, but you often still had them actually being within tolerance capacitance wise, just ESR was into the kilohm or megohm range, as the acid electrolyte evaporated through the rubber bung.

@nophead

9 ай бұрын

I learned zeners could be noisy as a child when I wired one between the base and collector of a transistor thinking that I would make a super zener but actualy l made a white noise generator!

@campbellmorrison8540

9 ай бұрын

@@nophead Now you mention it I recall seeing that as a white noise generator. but I obviously never understood how it worked :)

Marc, your repair was quicker than making a warranty claim! Seriously though, my 5261A came from a research lab and it was in a polished timber storage box, don't know of HP supplied the box.

@SeanBZA

9 ай бұрын

No, that would have been made by the lab for storage, likely they had hundreds of them and other instruments, so ordered the boxes to keep them in pristine condition when not in use.

For the modern HP experience, you could always angrily call "Customer Disservice", wait on hold for four hours, punch buttons for half an hour to get cycled through the same queue 20 times before getting a live person who listens to 5% of your problem, then puts you on hold into a queue that waits 30 minutes before automatically dropping the call.

@CuriousMarc

9 ай бұрын

So true...

@cpufreak101

9 ай бұрын

And when you do finally get through to someone, they just say "purchase a new device"

Please post high-res scans of that yellow tag so we can make bootleg copies! (yes really)

Nuvistors were used in the front end of the satellite tracking receivers at the Winkfield NASA STADAN station where I worked in the mid 60s.

I enjoy the stories told in the videos, but I love the fault finding. I rarely got to work at component level and feel I missed a useful and enjoyable career. Please keep the technical explanations in the fault finding segments, so of it may stick and I will get some use from the knowledge.

So much fun watching you fix stuff! 👍

Always a joy to watch your videos. May you have many more happy HP days!

Honestly, I expected a few minor problems after so many years spent locked in the box. Even semiconductors get old, you never stop learning.

@HebaruSan

9 ай бұрын

I am still waiting for sci fi to ditch the "robots are immortal" trope :)

@user2C47

9 ай бұрын

​@@HebaruSanDepends on whether or not they can repair themselves. If you have a triple-redundant, field-repairable robot and cloud backups on top of it, you can be effectively immortal.

@KallePihlajasaari

9 ай бұрын

@@HebaruSan Robots can clone themselves long before they wear out. Getting an upgrade every time. The hardest part for the sentient robot might be to turn off the original while it is struggling in the work bench clamps.

Always a satisfying experience! Great work 😎

Never seen those cute little tubes before, very interesting, and lovely 😍 Than you Marc for another well made and interesting video!

Nice troubleshooting Marc!

You really used to get what you paid for with HP equipment; a beautiful plug-in, manuals, and they even were thoughtful enough to pack an interesting troubleshooting video for you into the box free of charge!

Love it! Well done again!

Magnifique appareil, et la réparation est génial, tout cela date du temps où l'on pouvait encore réparer ses propres appareil, un grand merci pour le partage c'est à chaque fois un vrai plaisir.

I don't know if it was the unboxing experience you wanted, but it was perfect for us the viewers 😂 and 2 videos in a week? Bliss 😊

New in the box ... complete with manuals! very nice.

Counting equipment has always enchanted me for some reason. Even down to those rep counters that coaches use.

👿Darn, no true out of the box experience. But it wouldn't be the curiousMarc channel without a repair on "new" Old Stock. At least the packaging was all intact and the dessicant too! And as always, watching you and Eric slowly follow the signal and figure out the failure mode, totally worth while. It may be old stock, but now it is Operable old stock.

Marc, since you mentioned reforming caps that have been sitting dormant for years, would you make a video on the pros & cons of reforming caps? When can you safely reform caps and when should you simply replace them? Even the US Military Standard on reforming caps says that after a certain relatively short period of time (less than decades if memory serves) that caps should be discarded rather than be reformed. I ask because there is such a wide range of opinions between Engineers and on KZread about reforming caps that I'm definitely confused about it. Would you also cover how _you_ reform caps and maybe even show your reforming set-up?

@CuriousMarc

9 ай бұрын

Already done! Here: kzread.info/dash/bejne/eYGCs6aodtO_gbw.html

Ca fait plaisir de t'entendre parler français (ou belge). Amazing there's still some new old stock plugins around !

I'm all for test instrument Pokemon. Gotta catch 'em all!

I really really miss seeing schematics with electronic gear.

I love all the older HP equipment and the engineer written manuals, schematics, theory of operation. It's a source of good education in itself. Modern companies have given the creation of a lot of documentation over to the HR department which will point out that their equipment is superior in that it's designed and built for more cultural diversity.

Awsome!❤

I've used normal bipolars in reverse zener mode as noise sources for many years. That probably happened to your zener device as well.

Brand new unit already broken after unpacking? You should have complained to HP support! 👀😆

@CuriousMarc

9 ай бұрын

Yep send it back for warranty and argue that the 50 year delay in opening the box was just the postal service being slow 😆

@ydonl

9 ай бұрын

I think he IS HP support!

Nice! Real manual with schematics! And made when HP meant something.

OK, where did you get the time machine? Did you get the DeLorean or police box model?

@CuriousMarc

9 ай бұрын

Nah, I blame it on slow postal delivery. Package delayed in transit I assume.

@sanches2

9 ай бұрын

​@@CuriousMarcbahahaha!!!

Not too bad for sitting in its box for over 50 years!

Very interesting thank you.

Schematics.. I was very surprised, shocked even, to see full schematics for my 2010ish OTC GE microwave when I had to take it apart to debug a power fault. Was hidden inside the button panel. Some companies still do it I suppose.

There must be a warehouse in area 51 full of hp equipment still factory fresh from the 60s

C'est un plaisir d'entendre à nouveau la langue maternelle de Marc dans la chaîne. Merci du Canada pour cette superbe vidéo! (et désolé pour mon très mauvais français avec probablement des genres substantifs erronés)

@CuriousMarc

9 ай бұрын

Non votre français est parfait!

@whiskeytuesday

9 ай бұрын

@@CuriousMarc Only with the partial assistance of M. Le Google, I assure you.

I sure wish the original HP quality build was still around 👍

Doubted so little in voiding a “brand new” HP warranty 😂

Marc, better report those 40+ year old NOS component failures to HP. The product reliability engineering people might want to know about it 😁

@cpufreak101

9 ай бұрын

Honestly I'd say do it purely just to see if they even give a response lol, sometimes the customer service people like seeing something like that to change up an otherwise dull day

A Hewlett Package!

I think I had never seen a zener fail before. Cool! :)

@CuriousMarc

9 ай бұрын

Me neither. Every repair, I learn something! Hopefully the viewers do too.

And the question you are all asking... "Will it blend?" ;-)

Très bon français! J'aime regarder tes vidéo.

It seems to come with MRE (Meal Ready to Eat)!

The components were rudely awakened from their decades of slumber. The capacitor was quite short in its response and the Zener, still snoring, was quite noisy.

I wonder if those Culligan Humi-Sorb bags can be recycled in the oven? Personally I didn't know Culligan made those.

Oh wow! Your french accent is really GOOD ! [edit: heh, I didn't even knew you were actually from France!]

Ooooo the label was definitely plotted out and then photo-copied to make more 😍

Well, I was not surprised that at least one Sprague capacitor shorted. I measure them for shorts on anything vintage HP I buy on ebay before even powering on the instrument. I have a nice box full of them, maybe a guitar amp guy would love them! 🤑 Beware of NOS.... only buy it if you can repair it and want perfect cosmetics. Another thing I have seen a few times is the item being destroyed by outgassing from the sealed packaging. Usually soft foam. But it was NOS, sealed box... NO REFUND!!! Be careful out there..... 😉

"From a time when the HP name stood for something special" - ouch. I hope today's HP management get the message.

All those times you slip up and say 50Hz instead of 60... do you think you got over-excited by the manuel en Français and forrgot which continent you were on? ;)

You forgot to breath in the 50 year old air released by opening the box!!!

@CuriousMarc

9 ай бұрын

It did not smell like anything special. Nothing outgassed from that one.

Love how you allways have to be weary of old new stock, even if it looks as pristine as that amplifier. We tend to forget that electronics can go bad on their own randomly.

That type of diode fault may need a curve tracer to see it.

"...from a time when the HP name actually stood for something special." I know, right?

Is that a centronics connector on the back? Just like what our printers with a parallel port used to use?

@CuriousMarc

9 ай бұрын

Yes Centronics (actually Amphenol), just much wider. It was a connector from the 1950's, used a lot when you had many parallel connections. Made it all the way to the PC age!

@nzoomed

9 ай бұрын

@@CuriousMarc yeah its amazing how far back some of these connectors date to. My tektronix 561a scope has a similar type of connector on its modules too, quite advanced for 1960s gear. The engineering that goes into alot of this gear is incredible.

So is this where the term plugin originated from?!?

Always makes me wonder how the deep space probes electronics last so long? Voyager 1 and 2 for example. Do they burn in test all the components?

@CuriousMarc

9 ай бұрын

Yes, all components burned in and tested much further than normal ones in accelerated aging. Caps are solid state mil tantalums.

@senilyDeluxe

9 ай бұрын

Redundancy as well as having a Plan C (B already being said redundancy) helps. The Voyagers have tons of components fail. They famously had to rewrite the firmware to work around a bad RAM in the 80s.

Hey Marc, I have to ask (in case I missed it). What do these devises do? Who would have used them back in the day? Do you use them today?

@BBC600

9 ай бұрын

I'm curious too... It seems like (as a layman) it is a booster for video signals. Maybe it was used for Apollo to boost the signal for the TV broadcast?

@CuriousMarc

9 ай бұрын

@@BBC600 Ah, you probably both mean this particular plugin, the “video amplifier”. It’s a big historical misnomer, has nothing to do with video. It did at the beginning, but became a generic name for a very broadband, sensitive amplifier that goes from near DC up to 100’s of MHz. Here it’s just used as a preamp to increase the sensitivity of the counter by a huge factor. Without it, the lowest range is 100 mV RMS, with it the lowest range is 3 mV RMS. That’s what I try to demonstrate at the end of the video.

@root42

9 ай бұрын

@@CuriousMarcand it's broadband to give a big range of frequencies you can count with this module? And what about Apollo? Would they have used it to verify the signals were on the right frequency? Or to determine relative speed due to doppler shift?

@SeanBZA

9 ай бұрын

@@root42 Apollo to verify both that the transmit and receive side were working, and also to display the various carriers as well, selecting externally via switch boxes, so that you can verify that all the telemetry and command functions you were sending up, and got back, were within parameters. Also the doppler shift got you a velocity reading relative to ground, so that you could use some math, based on the antenna used and angle of antenna, to remove the error due to the rotation of the planet, and get a true velocity vector for the spacecraft out.

Great unboxing! Excellent French, of course, and also very good German! How did the interior of the package and the device smell, after opening? Interesting repair.. the elco dried out, evidently.. did the unit really rest on stock for 51years, now? Have you found any date codes?

@thek3743

9 ай бұрын

LOL, he is french :-)

@DrFrank-xj9bc

9 ай бұрын

@@thek3743 ..of course..

@CuriousMarc

9 ай бұрын

No smell on that one, nothing outgassed. The cap did not dry out either, it shorted. All other caps were in tip top shape.

Just in time for lunch

Would HP supply Apollo again if they knew about the maintenance?

👍

I noticed none of the gear in the NASA pick had the expansion plugin, what are they measuring that’s different?

@SeanBZA

9 ай бұрын

They were using the rear inputs instead, the plugins would be remote mounted in an external rack mounted chassis behind the console, and connected with a HP supplied extension cable to there. That way they could have multiple plugins around, and select them, only using the unit as a display, and data converter. Multiple modules, and then a set of those push button switches with indicators, to drive relay blocks that selected which plugin was to be used, and route power and signals to them as selected. Saved having a whole rack of counters to the roof for the controller, and also allows sharing of plugins via crosspoint switch arrays, so all can use a single set of plugins, and not need to duplicate it for each console. Just have 2 of the racks and crosspoints, so that you can switch to an alternate if one failed, or have 2 using the same data.

Question: How much time is actually saved by probing for faults, which seems to be the traditional way of doing things, rather than taking the PCB out and start out by measuring each component for values, drifting, shorts, et cetera? By measuring all of them, I would think you'd find all the faults in one stroke. At least, if more than one component is faulty, it seems that measuring all of them to start with, would save a lot of time in the end. Am I wrong here?

@CuriousMarc

9 ай бұрын

Sometimes we resort to it when we have narrowed down the fault to a handful of components, say less than 5, and it's a tricky fault, so it may indeed be faster. The reason that this is rarely done, is that it would take days to desolder all the 100's of components and test them properly one by one, even on this very simple instrument. And then, the Zener with the noise issue would have tested perfectly good on the curve tracer, so you would not have caught that. And the second bad capacitor is not in the plugin, it's in the main unit, so you would not have caught that either. So after days of hard but blind work, assuming you reassembled it right and did not damage anything, it still would not have worked. Blind repairing sometimes works on simple faults on simple items, but then not often. Generally you want to avoid it. You want to repair 100% of the faults 100% of the time. As you can tell if you watch the channel, a sizable portion of the units we revive were prior repair failures by people using random measure and replace techniques. We strive to teach the better way. But hey, it's your unit, your test equipment and your time. You are entitled to choose whatever repair method you like!

Perhaps it was a early tantalum capacitor. I have seen them fail more than any other.

Damn, Marc can speak French pretty well. 😅

Come on Marc, be honest. You'd have been disappointed if it had worked perfectly and gave no excuse to tinker. ;)

Pour la peine : je t'offre un pastaga saucisson ! ^^

@CuriousMarc

9 ай бұрын

Miam miam

sweeeeeet!

Any estimates on the manufacture date of the module?

@CuriousMarc

9 ай бұрын

Module is manufactured in 1971, and manual print date is 1972. So made in 1971, packed in 1972 (and opened in 2023!).

The never ending game ... good caps, bad caps

"Do not eat"...this product was from a time where it wasn't necessary to tell people not to eat the dessicant.

So sad to realize how far HP has fallen over the years. Bill and Dave would be so sad.

What exactly makes it a video amplifier compared to HPs other Amplifier modules ?

@CuriousMarc

9 ай бұрын

It's a pretty bad misnomer. See answer in the comment I just pinned.

@LukasLobmann

9 ай бұрын

@@CuriousMarc Thank you for the great explanation.

Back when HP was a respectable tech leader... Before they got into the $10,000/gallon inkjet cartridge scam. That kept the shareholders happy for a while I guess, but good riddance to them as far as I'm concerned.

@FrozenHaxor

9 ай бұрын

Worst company to buy anything from at the moment, disposable electronic junk. When a customer brings us anything from them for repair it's just falling apart, they even managed to make the plastic part self disintegrate after 2 years. They got the warranty period to the tee.

@StubbyPhillips

9 ай бұрын

Speaking of the inkjet scam, does anyone know if the "starter cartridges" actually have the roughly 37 fewer drops that it would take to fill them up or does the little chip just render them useless sooner? Either way, consider for a moment just how *_ABSOLUTELY SLEAZY_* it is to sell printers with "starter" cartridges in the first place!

This video reminds me of Steve1989 for some reason

Hey Marc, not to be that guy, but I thought HP stood for “Hewlett-Packard,” not “Something Special.” They would have to change their logo to SS, I don't see that happening. 🤣🤣 Still, excellent unboxing and repair, Marc. 👏🏻👏🏻

That was the best "porn" of the year

3:19 Du sprichst akzentfrei Deutsch?

@sanches2

9 ай бұрын

I was surprised too. Especially the last word ;)

Why is it called Video ? Thanks

@CuriousMarc

9 ай бұрын

It's a misnomer of historical origin. See explanation in response to the comment I just pinned.

@oldavguywholovesRCA

9 ай бұрын

@@CuriousMarc And now I know the rest of the story. Thanks Mark for the reply.

W00T

Why is it called a VIDEO amplifier?

@CuriousMarc

9 ай бұрын

I know, it's weird. It's a misnomer of historical origin. See the explanation in the comment I just pinned.

@deeiks12

9 ай бұрын

@@CuriousMarc Thanks for the explanation. It makes some sense now :)