I've never, ever, seen such high level nerdery put up to such good use. Keep it up nerds, I love you.

A sealed box from 1969 and it can hit 500.00042 khz without external locking. I'd say that's pretty good and a testament to the design engineers and the people who put it together.

in each chapter, more amazed at the electronic engineering used in those modules. you are like archaeologists discovering those secrets. THANK YOU

Apollo never gets old!

Marc and friends, thank you for this fascinating look into historical hardware! Your video's are so well made and don't dumb down anything. Thank you for respecting your audience and not giving in to the standard annoying youtube practice of reminding to like and subscribe!

In 1976, I worked in the factory of a Skokie, Illinois manufacturing company. My boss was a great guy who was once an executive at General Time Company in Elgin, Illinois. He told me the story of how his company sought the contract to build the Apollo central timing unit, and was so proud of their part in the Apollo project. General Time built some prototype clocks using the very best parts and techniques available at the time, building them to exacting NASA standards. My boss traveled from Chicago to Houston with two copies of the prototype in a briefcase sitting next to him in an adjacent seat on his flight. He delivered the items to NASA and General Time won the contract. He told me there was a switch on the Saturn rocket that activated when the rocket lifted off the launch pad to start the clock. If I remember correctly, the whole vehicle had to move up a short distance to trigger the switch.

I can remember my family huddling around a small black and white TV to watch everything and anything about the Apollo missions, especially Apollo 13. We we all so glad to see them make it back home. Thank you all for bringing all this stuff back to life. You guys are all amazing. Such brilliant minds all coming together.

Eric's magic finger strikes again! This time outputting binary

The ETU is welded closed to ensure 100 percent reliability. If the magic smoke can't get out, the unit won't stop working.🤣🤣🤣

I send Apollo deniers to this channel! Some old timers had difficulty wrapping their heads around IC's and multi via boards from this period, when discrete consumer electronics were so large / bulky Keep up the good work, been following this channel since your droid!

I wish I had the time and ability to work on stuff like this. It's so fascinating to learn about the early days of ICs and how it was used by Apollo. Having a full scale modular replica of the insides of the CM & LM panels that you could actually operate would be a dream, but I would settle for a digitally simulated version.

First off, outstanding non-destructive modification of the HP counter/DVM; that is as clean as it ever gets--fantastic Marc & Crew! Next, I was really taken aback by the 'all-eggs-in-one-basket' approach for the central timing unit; but even more impressed that everything has backups in both time generation and power supplies--really impressive defensive human-rated design work! Every time I look at NASA design documents I REALLy get and education---what smart people! Finally thanks for working on these NASA space projects; I hope you are able to find more in the future!

I know it wasn't absolutely necessary, but it was certainly appropriate to get the HP Nixie tube counters doing some real work (keeping mission time of course). Kudos once again, and much respect for making that mod to the HP counter reversible. No detail spared, EVAR!

oooh I love the counter modification! It's so clean and simple and totally shows off an almost natural understanding of the inner workings of things. It's beautiful!

The joy in his face 😍

That's how you engineer for reliability! Lovely tech, as always on your channel. Apollo time in the Artemis age... Loveliness increases, it will never pass into nothingness. IC substitution is a cool hack. So, mission time clock is green and go for launch :). As always, waiting for the next one!

How many devices are we away from launching an Apollo rocket? 😁The collection is growing and growing, very nice, love every bit of it. 👍

Truly inspiring videos, cant get enough of watching you and the team troubleshoot and come out successful please keep the videos coming can’t wait for the next!

THIS IS REALLY "hANDS-oN" ENGINEERING,SOMETHING THATS NOT TAUGHT ANYMORE!Well done!

Another fascinating piece of the puzzle. With all the bits of the Apollo program you guys have now I am just waiting for you to announce a launch date 🚀

These spacecraft sure seemed to have a lot of extra mass in the cases of the various boxes. I guess the Saturn had enough poop to lift it all. With every advance in this project, I become more gobsmacked with the brilliant persistence involved in the sleuthing.

"And the award for coolest clock EVER goes to:"

That was GREAT Modification !!!! I love this channel !!!!

Marc, your videos, all of them, inspired me to unearth my vintage (1991) Laser Precision Corp. TD-2000 OTDR. I know you'll know what it is. It took forever even to stop it tripping the earth leakage trips, blowing fuses, and then all the other niggles you get with a vintage 8088 machine that was used as test equipment. It works beautifully now, but throughout the whole process, in the back of my mind, I was doing a commentary in your style. My name is also Marc.

I am fascinated by the technology of the Apollo project. Congratulations on the excellent work you are doing.

You and Eric make such a great team, I'm so glad y'all have been able to collaborate on all this amazing stuff! 10/10

It makes sense, considering the number of places timing signals went, that "the clock has started" (or similar wording) was important enough to call out at liftoff.

Completely in awe.

My Grandpa worked at general time during this project, though he was in a different department, working as lead engineer on what would be the first LED clocks for westclox. He always claimed that he knew a guy that worked on this. That was a genius mod to the nixie counter!

Always like your videos! And to see old HP and keysight hardware at work is also a great enjoyment to me because at my job we work with new keysight equipment, and to see the evolution of this is great.

thumb up at the beginning of watching like always - strong follower ❤

just amazing - as ever.

amazing tech....tks for post Dinos

Interesting to see "crystal oscillators" at that time. It took some time for them to be finally added to the small confines of a wrist watch.

It would be interesting to see the specification documents that were sent to the manufacturers to describe all these boxes.

Hi Marc It's my very first own comment on your channel and one of my very few here on youtube. I really love all your content here and as a HAM radio operator from switzerland I love it twice! I hope to hear you maybe one time on one of the HAM bands or in person! Kind regards Simon

Wow, using a hotplate looked way more effective than a hot air gun! So many people accidentally blow the chip around or apply the heat unevenly. Just plopping it on a hotplate seems pretty foolproof!

More Apollo love from the guys! It is a good time to be an Apollo geek.

Apropos absolutely nothing, I used my Big Ben alarm clock in the late 50's, along with a mousetrap, non-safety wooden match, sandpaper, custom bracket, and small unsafe but sane bit of 4th of July tomfoolery, to make what might be called a timed noise-making device employed outside my sister's window. I don't recall how successful this all was, but it was great fun to construct. The important aspect of the Big Ben was that the clockspring winder on its rear unwound rapidly when the alarm sounded.

Excellent work! And those xray guys are doing some really smart advertising for their lumafield / CT scan service.

Great solution for the aerospace connectors! Those connectors (even the rectangular ones) *are* available, they're just expensive. For an indoor application, your adapter is perfectly adequate. Cheers!

You guys are getting really good!

pretty amazing!

10:01 love the high precision, low emissions foot stabilizers. Mint. :))

That was a really nice hack with that HP instrument

I was so much expecting this chapter !!!! You are legend !

Mike mentions Y2K. I remember living in fear on Jan 1st 2000, until some very minor piece of software failed and needed an update. For some reason having had a problem, I felt massive relief. I had experienced my Y2K bug and all would be well from that moment, which it was. I guess I needed something to go wrong just to release the stress and feel better rather than waiting with ever shortening nails.

That thing you called a solder mask is a stencil. Solder mask is a layer on the PCB itself.

Nice work as always

В моем 📺 установлена та же российская технология... и она до сих пор отлично работает!

Nice Progress another plus for the team.

Really creative solution for the clock display.

Now, for extra credit; Design and construct modern replacements for each of the spacecraft modules using currently available production parts. Special exemption will be allowed for incredibly specialized components which may not be currently available due to lack of demand. Additional points given for creative use of modern components to replicate functions of unavailable parts. The design brief is to create modules which are smaller, lighter and equally capable while meeting equivalent reliability and fault tolerance of the originals. New modules must retain interoperability with original units. Sorry. I couldn't help it. I can just imagine how hard a task like this would be to try and attempt. Your work is amazing, and it is so good to know that this knowlege is still out there.

Amazing technology, amazing reverse engineering. So inspiring ! :)

Amazingly Nutz! In a good way…😀 Love your work….👍

Nixie niceness. 👍

Well done 👍

Hello Marc and the Apollos, First of all, thank you for your inspiring videos. Despite your tremendous knowledge you never let us people feel dumb. Instead you inspire us to keep on to be curious and explore! One question: Since the successor of Saturn V didn't made it today I watched again the Apollo XI movie from Todd Douglas Miller. If you watch or even simulate the landing of Eagle from minute 0:47:37, can you confirm that altitude and fuel levels are realistic or somehow dramatized? Thank you very much! I am keeping fingers crossed for Starship. Hope that you folks get old enough to re-engineer the modules of Starship and I am looking forward to watch it here😄🤞

19:50 I'm sure this unit in the making is generic kit. I saw one shown on the opening titles of the 60s film Ice Station Zebra (Rock Hudson) @ 1:30 in

20:44 - Yes, try it again, this time with feeling... but if you don't get it working, Dr. Klahn will send you TO DETROIT. We are building a fighting force of extraordinary magnitude... we forge our spirit in the tradition of our ancestors.

Nice job!

you guys are MAD! In 20yrs you will be ready to launch again!!!

Ooo... more clocks.

Очень интересно 🎉

amazing😃😃😃

Getting closer to launch! 🚀

Wohhhoooo 🥳🥳🥳

All AGC chapters and others should be considered historical documents. It would be great to bring together the designers who are still alive to pay tribute to them, for having created this thing that still works today and inspires hundreds of nerds, sorry, ... I wanted to say "interesting" persons, ...

It looked like the logic signals coming out had an amplitude of 6V, yet you were (presumably) using TTL parts to decode it, and later the 74HVC04, which take a maximum of 5V in... Did you do some level shifting somewhere? Also, do you know what kind of logic was in the box? DTL or RTL...? Very interesting stuff, can't wait to see more!

2:27 whoaaa

It would add to the readability if you could put decimal points between DAYS, HOURS etc. Not sure if it's got that many decimal points though...

That would make a Niiicccce alarm clock! ⏰ wow can you imagine bedside Apollo artifact💗

A lot of military/space grade equipment schematics were silkscreened on fabric included inside the units. Was there something similar in this device?

Nice

Every time I watch one of these videos I feel dumber. These guys are just phenomenal.

Is the rectangular connector a en4644 or the slightly thinner shelled version (which has an en number which escapes me)

When are you going to build the capsule itself ? 😁 It is mountblowing how you are able to find that stuff. It is not that they made 1000's .

Very cool!! I have an hp nixi volt meter of the same form factor, possibly the same nixie board you have there. You are giving me ideas for future data display needs, THANKS!!! Right now it's an HP high res volt meter with a blown high pressure mercury-reed relay that exploded on me! I don't like those relays. I won't gut the volt meter section, it's a work of art. But I'm not going to replace the relay until I know why the last one exploded with minimal provocation. It shot glass against the wall behind me (and it's small amount of mercury). I just barely bent the wire running into the "containment" housing and BANG!

Marc, has there been any attempt made to database and contact every person still living associated with engineering and design of Apollo's systems?

👏👏👏👏👍

CuriousMarc and Ben Eater on the same day! I’m buying a lottery ticket.

(@21:16) Now, modify it to show the correct stardate; this way, the Captain’s log will be correct. 😌

Not an Apollo CTE. It’s a Discovery alpha echo-35 unit.

This is getting interesting!!! This channel know has an Apollo and Soyuz series at the same time. Cold war race to the moon again?😁

wow nice video. In some ways it is almost like people never went to the moon as this lost information has to be reinvented to get back to square one. 😎 Thanks.

So. A big question. How much in your collection is missing to rebuild all the avionics of the apollo capsule?

Nixies never get old either!

Liftoff! The clock is ticking!

Is the CTE filled with anything? awfully high density with no air movement for cooling

Happiness while having Covid is being up for a couple of hours to discover a New CuriousMarc video!

What was the trigger for the MET to start? Was it the end of the countdown? The vehicle clearing the tower? Or something else?

9:10 no magic smoke?

Is there a reference to which Deutsch company made the multi coax connectors? Deutsch is German for German, so that may only be a small part of the information to say who made the connectors.

What makes a PCB cute?

14:30 Using a Mastercard Gold would give you much better results!

Emulate all on a Raspberry PI 😃

00:50. Well HAL, I'm damned if I can find anything wrong with it.

Slightly more ridiculous, but you could have used a CPLD or FPGA to switch between native HP mode and BCD input mode.

At 20:43 they turn on the clock and it starts counting from 1 instead of 0. I'm not sure if that's important or not. But I wanted to point it out.