I'm drunk and just love the video :-D

Amazing, I never saw one working.

How i can make 1000000k likes?!?!??!

Only 200k subs??? Humanity is just stupid!!! You are the leader!!¡

You are sick guys!!! I would not be scared to fly with you to space!!!!

I don't mind hearing the elevator music early. I always look forward to that part.

We need to see that radar analog machine torn down and reverse engineered, and see it working!

I have a PLL module in my modular synthesizer. I picked it up as an affordable means to add extra depth and character to a voice. Mixing in the square wave synced to the main oscillator helps fatten the sound, and adjusting to have ot not immediately lock when the pitch changes can add some unpredictable excitement to the sound. Thanks for the info regarding demodulating fm signals. I will be patching up a use case for that.

As ever - just amazing!

Simply spectacular! WOOOOWWW. you took me in the seventies like a time machine. 😅 The vacuum loading blown-up my mind! 😯😯🤩🤩 It seams the tape has its own life...hahahah😂 Where and how did you find those incredible old devices and how do you know how to get them to work? What is your background? You look very young to be so much skilled to use those devices...😲 Very, very interesting! Thanks for sharing! 🙏 Subscribed, of course...🤓

If this is nuke luncher

Around 15:20 : I've used one of these 'portable' PC's from IBM in the early 80's (but liked the ITT-3030 I used before the IBM PC was launched). You could use an external color display, have an Excel-like worksheet open on the internal display and simultaneously show the corresponding graph on the color screen

You started describing PLLs and the 4046 and my mind just went off on a RADAR tangent... doppler shift happens small scale as well, and combined with reflected signal strength and a mechanically swept directional receive antenna you could derive bearing, azimuth, and relative speed. Neat.

Three more years and you'll be ready for launch

interesting, i missed 6 videos for which i didn't get ANY alerts for... there are some wacky things behind the scene....

I could watch this for hours!

Fabulous work Marc. Didn't understand much, but fabulous work!

My favourite phase detector is the 4046.

One of the coolest aspects of Phase Locked Loops that isn't covered here is that by inserting a combination of multipliers/dividers into the feedback path, you can get a PLL to generate an output frequency at an arbitrary ratio to the input frequency while still maintaining a phase relationship with it. This trick is used extensively when synthesizing various clocks at different frequencies in modern systems, as it produces very stable output references from a single high-quality input reference. That reference usually comes from a crystal, and is usually at much lower frequency than the output because it's hard to make good crystals that resonate at hundreds of megahertz or higher.

love the artwork during elevator music time, where did they come from?

At 16:49 I wonder why they went with the "dead bug" mounting method for the transistors? Seems kind of odd to me for someting of this production status, although I do see "dead bug" in NASA standards. More a Bob Pease prototype method, I think.

You guys have your hands full. PLL technology from that era was fairly sketchy.

I want one!

Seriously, Marc, the level of fearlessness is downright astonishing, not to mention the comprehension. This is world-class stuff! 👍

In my time as a service engineer, PLL were the most difficult circuits to troubleshoot. Specially if it was distributed through several boards. There was no point where you could start from, as every signal was wrong. An off tolerance resistor or capacitor, a resistive short between two tracks, could generate all sorts of issues all over the place.😊

PLL has actually been in use before WWII, e.g. in analog TV

I often wondered if Marc does the voiceover for the "One moment later..." lol I think one important thing to mention about a PLL, is that once you are locked on to the incoming signal, you can then use the PLL to produce multiples of that frequency, but still keep it phase-locked. Digital PLLs / Fractional-N DPLLs are of course still used to this day in things like FPGAs, and your modern CPUs. Very very handy, especially when especially when you require a weird clock frequency to recreate an ancient arcade board. lol

There could not be a more fitting YT channel for the “stay tuned” closing text..!!

This story is endless. It was "restoring all the Apollo comm equipment" for a long time, and now it's "upgrading repairing and maintaining all the Apollo comm equipment" ;)

This is exactly why I’m never going to buy another used lunar rocket ship ever again.

I've recently been playing around with Op-Amps and I was thinking that if you wanted a very over-simplified description of a PLL you could say "It's like an Op-Amp but for frequency rather than amplitude"???????

Thanks for the nice explanation of PLL - not getting too far into maths either. SCE to AUX, this never gets old! "You cannot trust the indication when you don't have modulation" makes a nice catchphrase. More of it, please.

Love it! The PLL elevator description was super cool. Those pioneering engineers were incredible

Once again the equipment shows it was built to last. Hell, if you found enough parts, you could probably assemble an entire Saturn V stack with an Apollo module on top and still launch it today.

Lovely. I could listen to that all day. So relaxing.

Ah yes, user error The bane of every engineers existence

Those mini marshals as monitoring amps are a great idea! I’ve been looking for something like that recently and was thinking I might have to build my own - but just stuffing a BNC on the side of a mini marshal would do the job so much better!

that episode comes at the exact time I'm trying to build a circuit to replace a temic U2860B and ST TSH512C ...

My iPhone phase detector unlocks every time I go near it. With others phase error is always an issue.

素晴らしい動画です。懐かしくて、懐かしくて。　大型汎用コンピューターの最終試験と客先納入、引き渡しまでやってました。一部屋を占有し、数人で数週間かけて客先で組み立て、テストプログラムを流して動作確認後、お客様に納品しました。日本でも、どこかこの規模のコンピューターが動作可能な状態であるのでしょうか？

I tried to fix a y-x Plotter 20 years ago. Today I'm sure it used some kind if PLL to drive and hold the axes morors. I never got it working, because i never could wrap my head around how they could sub millimeter accuracy over am A1 paper from two 8 bit DACs. The motor didn't had an encoder on it, just an detector when a full revolution occurred. The circuit somehow used the four poled motor windings itself to detect the current position and hold it.

Cool breadboard

Oddly I am dealing with a broken Honeywell MS-2T panel meter at this very moment. What are the chances?! Mine seems to be missing the spiral spring. It’s just… not here? Now I’m looking at your microscope shot over and over again. Great video as always!

Wow, that was a case of beer project!

You guys have way too much fun.

My guess is that some scientist in Russia has this all figured out and a working setup!

24:19 "How many colored rings to mark your oscilloscope probe?" Marc: "YES"

Been there many. Done that, once. Once was enough to teach me the testing sequence with such loops. I was half worried at the start that the NASA loop required the voice loop to be on frequency giving you a loop within a loop situation. That is obscenely difficult to work with. So I abandoned it back in the day. Anyway you had me mentally screaming, "Check the bloody VCO voltage!" And when you discovered things behaved better when modulation was turned off on the incoming frequency I gently and slowly shook my head. Incidentally that Motorola phase detector derived circuit has a possible problem feature for you to deal with. Right at zero phase error it has a small dead band. That can give very annoying loop testing problems. Now, if you try to implement that FM demodulator with an SDR - note that almost all SDR PLLs I have seen feature an arithmetic underflow and don't work right if they use simple "float" rather than "double". Fixed point "int32" might work. The two pole loop filter falls back to single pole operation, frequency lock without phase lock. {^_-} Boy howdy that takes me back a long way, to the early 70s when I first played with PLLs.

I remember using "PLL Tones" in order to access 2m repeaters. You could transmit on the repeater input but if you did not include the PLL tone, the repeater would not "accept" your input. I recall that the PLL tones were frequencies that were preset in the radio and from which you could select.

Great job Mark and gang on the whole Apollo series! Miss you guys from Maker Fair days and electronic flea markets since we moved to AZ. Hope to see you around.