WWII USAF Gyroscope Spin Up and Turntable Test

We spin up Ed Thelen's Sperry C-5 military-grade direction indicator gyro. Design is from 1949 and it still works wonders. We also repair and demonstrate the self-leveling feature. Finally, we mount it on a high precision Ideal Aerosmith gyro turntable for testing.
Many thanks to Ideal Aerosmith for sponsoring the table control software.
www.ideal-aerosmith.com/
/ @idealaerosmithinc.5543
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Contact info: kzbin.infoa...

[@sipion697]

I now figured out that jet engines aren't loud at all, in fact the noise is coming out of the gyros 😁

[@bobl78]

there are videos about powering up aircrafts from cold shutdown where you can here everything spinning up .. yes it´s quite loud indeed.. also there has to be a constant flow of cooling air through the cockpit panels to cool all the instrumentation and other stuff in there

[@Mach7RadioIntercepts]

Air flow around the fuselage is pretty loud too, especially at high speeds.

[@christianlingurar7085]

ever been in a tank? when idle, the gyro indeed is louder than the motor. but I guess tank weapon gyros are a little bit more massive than flight gyros...

[@johnh9808]

Can confirm. I work in an avionics and aviation instrument repair shop. It's loud as heck all day... Lots of 400Hz in addition to the sounds of the impeller fins blowing through the erection vane ports. Canned or not, they're all loud when they hit 13,000 to 20,000 rpm. The rotor balancing room is even louder than the production floor.

[@rogervanbommel1086]

@@johnh9808 well, that is interessant

[@gmcjetpilot]

Looking at OLD technology gives us appreciation for what we have and expands our knowledge. We should not forget how it was done because that is the key to the future. There is something magical about mechanical gyros.

[@miladirani4313]

👍👍👍

[@TheRasteri]

"Aerosmith Turntable"? I pictured a record player with Steve Tyler's autograph on it

[@reneschmitz4845]

The effort and machining that went into these instruments is amazing. So well crafted, that they work well even after all that time.

[@bobl78]

also imagine the maintenance it required.. the contacts and bearings didn´t last forever... a while ago I read an article that it really gets a problem for the owners of old planes to keep them airworthy in the original configuration because there´s no one around any more to maintain and repair the old avionics any more

[@weefek]

Except for the amphenol connectors. State of the art 40 yrs ago but garbage now and so many people still use them

[@ojkolsrud1]

@@bobl78 Just send it to Marc, he and his guys know how to fix it!

[@SuperAWaC]

@@bobl78 There are people around who can fix these things, but they are individuals who can only fix so many things at once.

[@SkyhawkSteve]

I was doing sensor design for an earthmoving equipment manufacturer, and we had to buy a similar turntable for testing the rate gyro performance. It was bigger, but still cost $50k about 20 years ago. Pretty neat device, though!

[@sanches2]

Thanks, Ideal Aerosmith! And thanks, Marc for another interesting episode :)

[@mumblbeebee6546]

Thank you, Marc, for always bringing such lovely things to us - and many thanks to Ed of course for selflessly offering his previous items for experimentation!

I liked your spin down editing following musical notes! Nice touch of perfectionism! Keep up your good work!

[@reneschmitz4845]

Welcome back to the channel: In this episode we play an Aerosmith Album on a make shift recordplayer. :)

[@SamMcDonald83]

What would be the ideal Aerosmith Album...

[@LastV8Interceptors]

Loved the demo at the end. Thanks so much for all these videos.

[@oak_meadow9533]

thank you Ideal Aerosmith !!! This kind of sponsorship is a total win for everyone involved! Thanks Marc for enabling and facilitating these kinds of demonstrations. You lift the public's mind by your explanation of technical hardware. It is one thing to see it in a text book , but oh so much better to behold a working model!😊😊😊

[@theharbinger2573]

looks like a 22 bit angle encoder on that gyro tester (360deg with 0.0001 deg resolution) - that is impressive, I would love to know what they use as a sensor for that. Probably at least a part of why it costs 50gs . Thanks for the dizzying array of gyro content Marc.

[@Chris_In_Texas]

Love the sounds of gyros spinning up. Every time I was in the cockpit was a great sound when starting switching all all the avionics! 👍 My friends yacht has multiple Seakeeper Gryo's and they are large water cooled units, that take about 55 Mins to reach full RPMs. Each of them weigh in at 1210 lbs and reach 9000 RPMs.

[@unicorn7337]

This channel is pure gold for electronics engineers and aviation enthusiasts. Thanks for all the awesome work you do to share these things with us Marc!

[@richfiles]

HUGE props to Ideal Aerosmith for hooking you up with the software! They exactly sound like the kind of company I'd love to work for or do business with!

[@scottrogers8100]

You Sir are my kind of guy! This is a fantastic demonstration of historic and ingenuity at it's best. I wish I had a seat in your shop just to watch you do your thing. Thanks for this video!

[@ubergreenguru5704]

This video was ENORMOUSLY FASCINATING! Thank you!

[@adamdenner867]

Amazing! So cool to see it all working

[@jablingatigjengaman6791]

I use a larger ideal aerosmith rate table where I work. It's awesome! Props to those guys for helping you out

[@BIGWIGGLE223]

Wow!!! These guys were reinventing accuracy and reinventing it on a level that even 50 years later it is still magical. I love hearing stories from the engineers that were involved in the beginning of NASA and just how insanely hand built most of it was. Almost every single little part of the Space Program had a human doing the work. And where machinery was involved, it was old school Bridgeports or CNC unlike most people think of it today. It was all on those old school punch cards that my parents told me about using in computers of the day. Thank you for sharing that awesome little big piece of history with us all!!

[@account0199]

Love the fact that at the end you made it play a scale with the editing

[@hernancoronel]

Love your toys Marc and especially your ability to put them to work quickly and make art like this video! AWESOME! Thank you and keep up the great content!

[@CuriousMarc]

I love my toys too...

[@tekvax01]

Way COOL Marc!!!! I have always wanted one of those avionics gyroscopes!

[@ke6gwf]

I love how the startup keeps sounding like it's finished, but then starts accelerating again. I suspect it's something to do with harmonics and resonance, sounding quieter at certain speeds.

[@kransurfing]

indeed, it phasing through series of harmonics is why :)

[@MarcelHuguenin]

Guys, guys, you just have to be a little patient, I just watched the episode in full glorious HD 😉 and listening to a gyro playing a scale going downward while shutting down. Marc, you just have the most beautiful collection of toys to play with 🤣while also having the knowledge and skills 🤓 to be able to fix the stuff. Absolutely brilliant, my favourite channel 👏🏻👍🏼😎

[@chenguefer156]

Gyroscopes of this kind are really beautifull instruments. Many thanks for sharing!

[@Robothut]

Fantastic demo. Thank you.

[@petergottlieb1550]

I love the sound of these things spinning up. I have a nice collection as well. My latest project is getting an IMU fired up. Figured out the power and how to start it and the platform erects. Now it starts getting complicated!

[@isettech]

Nice. I inherited the same C5 Gyro from my dad. Looking forward to spinning it up.

[@SidneyCritic]

That was nice of ideal-aerosmith, thanks guys. Looks the the contact was running on the rough section and got caught when it was running in reverse, because the arm looks bowed/rolled up from the reverse force.

[@keith77mn77]

Those contacts are completely independent of the gyro rotation direction.

[@50shadesofbeige88]

I'd love to get a recording of the gyro spinning up uninterrupted. What a powerful and fantastic sound!

[@harrowtiger]

Congratulations Ideal Aerosmiths on your great donation of the testing software.

[@phuzz00]

I'll definitely keep them in mind next time I need a laboratory-grade gyro testing platform :)

[@metatechnologist]

So I could possibly use this to orientate my ham antenna then?? Thank you to Ideal Aerosmith for helping Curious Marc out in his journeys!!

[@richfiles]

I've been working on an off for years on a Kerbal Space Program Instrument panel, and one of the devices I picked up was an ADI. I found an ARU-11A that supposedly was salvaged from an Israeli F-4 Phantom flight trainer. It's supposed to take a 115vac 400Hz reference for both power and synchro reference, and then there are 3 syncro inputs that are supposed to be sent by an IMU's gyros to control the 3-axis ball. I hope to build a relatively simple synchro emulator using a series of DACs that can attenuate an external voltage reference fed into them, and a series of analog switch chips to select between polarized and no polarized sine waves generated from the reference source. Those outputs need to be generated for up to 28vac. I'm generating my sine wave from a vintage California Instruments Invertron digital oscillator. Unfortunately, I don't yet have a working inverter either... Need to be able to use that sine wave to drive a 400Hz AC inverter too.

[@MadScientist267]

I used to work on marine Sperry gyros... Very interesting devices... Initial spinup and precession stability routine (at least the very first part of it) is rather peculiar to witness.

[@SeanBZA]

Especially as they age, and turning off and disabling the automatic caging, which results in it doing a whole dance routine. Now all Marc has to do is find a gyrocompass and repeater unit, and the fluxgate sensor that provides the input, or even a complete 3 axis artificial horizon setup, with the gyro repeater and attitude all in the ball. The electronic ones look similar to the mechanical, but the mechanical ones are still in use as the standby AH and heading indicator on all aircraft, as they can be run off the battery, with the small standby inverter to provide them with power, 115VAC at 400Hz.

[@MadScientist267]

@@SeanBZA These do more than the marine variety. The ones I worked on were heading only and used nothing more than precession to work... Really only 2 halves to the electronics... The "inverter" for driving the motor (that's a peculiar design in itself as many of the marine varieties Sperry used SCR based switching)... And the counters (decoders) that send the pulse train sequence to remote display units and other equipment that can use the heading information. Purely mechanical, and took as long as 6 hours to stabilize from initial spinup, the time it takes the earth to rotate 90 deg and lock it in. Could be shorter if you either helped it stop oscillating or it worked its way into position earlier than normal.

[@smeeself]

@@MadScientist267 Thanks, I've been trying to find out how long it took the Apollo gyros to spin up. This gives some perspective. Cheers.

[@MadScientist267]

@@smeeself I'd be curious about how that worked as well

[@christianclark1354]

Love seeing it stay perfectly level as it spins around. This would make an awesome display in a museum.

[@RWBHere]

Heh! I like the octave at the end! It's great to see it working. I haven't had a Sperry gyro in my hands for over 35 years, and that one, which was very similar, came from a fishing trawler.

[@tbp-channel8870]

Great precision stuff .. never seen such before.. thanks !

[@KallePihlajasaari]

You have the coolest toys. I had the loan of a civilian rate gyro from a plane once with bearings that were toast, it would still spin up and make loads of noise and indicate but it would continuously null in a minute or two.

[@jlwilliams]

So does this mean that once CuriousMarc and his team succeed in building their own Apollo IMU, they'll be able to test it one axis at a time?

[@Murphistic]

At this point, I'm waiting for an upcoming video, where they unveil their replica Saturn V with the fully functional command module :)

[@MattOGormanSmith]

If this one is characterised, it would assist in emulating a 3 axis setup with an arduino and cheap MEMS gyros.

[@brandona1370]

Yet again I am completely fascinated by your work! Oh how I covet your equipment...

[@williamogilvie6909]

Very enjoyable, merci beaucoup . The white stuff inside the gyro is mold. Denatured alcohol on a Q-tip cleans it.

[@Nightsd01]

Amazing to see those 3 little wires powering that beast! Gotta love high voltage AC

[@MillwalltheCat]

Sweet! I picked up a rather sad looking Ferranti, MkIID Gyro-gunsight, and spent many happy hours returning it to its former glory. Both the reticle, and mirror gyros work beautifully. I just need a Spitfire to fit it into...

[@CuriousMarc]

Well done!

[@wirdy1]

Superb. Those gyro sounds will be music to the ears of fellow Nav Inst aircraft techs.

[@SuperVstech]

My grandfather worked with the sperry gyroscope division in the late forties, and the 50’s… he may have touched this very scope… John Francis Sheridan

[@kisslab]

Can you show us the 15°/h drift please.

[@TechGorilla1987]

Ed is a national treasure! When he was feeling the warmed screen of the gyro, and he exclaimed "INDEED!" I got the Mr. Phineus J. Whoopee vibe ala Tennessee Tuxedo and Friends. It really made me chuckle. You have to be as old as me to understand that reference. Phineus J. Whoopee - you're the GREATEST!

[@latmask00]

Happy to see Ed!

[@JoeSmith-pe5we]

Marc, could you do a full HD video and audio spin-up and shutdown of the gyroscope? It has an amazing sound.

[@aserta]

So early i can watch it in glorious 360potato vision!!!

[@graffie]

Yes, I was so confused at first why Marc would upload in such quality, but we're just faster than youtube. :P

[@philorkill]

Curious indeed. Cool stuff!

[@ArruVision]

0:07 That Tetris music took me from zero to chills down my spine in a second!

[@lukasandrysik3666]

Excited to see new video but I think it deserves better quality than 360p so I will wait :)

[@Likeaudio]

That is a serious investment there. I like this so much

[@lordskeletorde]

I love the sound of gyros spinning up.

[@thiesenf]

Washing machines doing their spin cycle is equally fullfilling...

[@mikeznel6048]

@@thiesenf Where is my sandwich!

[@d.jeffdionne]

How much current does it draw at 115v 400Hz 3Phase?

[@leon545b]

As a former Cessna 172 driver, this doesn't sound any noisier than the electric rate of turn gyros on the planes I flew. The DG (directional gyro, which is what you have) on those planes was vacuum driven, and only operated when the engine was running, which made a heck of a lot more noise than the gyros... ;-)

[@thenickdude]

I've seen a glider with a similarly-loud gyro, but in a glider the extra noise is really ridiculous. Bring on the MEMS gyros!

[@cliffordyapp2110]

You guys sure find some interesting auctions to attend! Is the plan to try and feed outputs from the Apollo gyro back through an IMU emulator into the Apollo flight simulation and see if you can get the simulation to react to motion reported by the gyro?

[@thiesenf]

"You Spin Me Right Round" - Dead Or Alive...

[@forbiddenera]

F* I love the sound. Reminds me of an old hard drive spinning up

[@rsc4peace971]

Ever since I was 10 years old, I believed in and was fascinated by technology without knowing all the science/engineering behind them. They simply were magic but REAL. Well, now even after my retirement as a Ph.D. scientist, I am still amazed and eager to learn more about anything STEM related. You guys are just top of the heap in showcasing the marvel of STE that perhaps >90% of the world's population may not have known or been aware of. BTW, are the gyro controls in modern spacecraft are by MEMS-based?

[@MeriaDuck]

That Shepard tone at start up ❤️

[@hardwareful]

I'd have loved to see it rotated while spinning at low RPM to show that it actually *can* accumulate an error. It' too perfect :)

[@jmalmsten]

I've always been curious about gyro effects. Especially since I heard that many of the sweeping tracking shots in Das Boot was shot with a spinning metal disc strapped to the film camera because a full sized steadicam was too big for the cramped space of the uboat set. And more modern electric gimbals with brushless motors wasn't invented for a good few decades.

[@youbecha64]

Nothing more fun than tumbling the gyros doing aerobatics...as far as noise...it does seem a bit loud, but normally those are behind a metal panel...and you have some kind of headset on with a comforting 400hz background noise... Modern big acft have the actual gyros in equipment bays, and just the displays are in the cockpit.

[@t.d.5804]

using a russian horizon here in my Yak52 (plane, made in 1980), power supply is an electric motor/generator for the 3p power. So there is a lot of noise from the gen and the gyro. There are modern power supplies which replace the old motor/generator. Saves a few amps, a lot of weight and is much more stable.

[@VictorianMaid99]

outstanding !

[@EggBastion]

what a cool sponsor

[@SuperAWaC]

my grandfather worked on the direct predecessors to those IMUs which were used on various ballistic missiles.

[@SuburbanDon]

Very cool !

[@raygale4198]

I'm sure we have lost so many skills with modern electronics, the gyro is a marvel of mechanical complexity, relying on first principles of physics to work. It's beautiful.

[@andymouse]

Very cool company !....cheers.

[@Unix2816]

Where do you continue to buy stuff like this CuriousMarc ?

[@decon4611]

Ed: I should really Apollo - gize for that... This quote should be made into a shirt with a picture of the gyro schematic

[@SirWolfCZ]

CuriousMarc, congratulations on a great new toy! Please tell me where one might find the rendition of the Tetris tune used at the beginning of the video. I like it very much and have not been able to identify and find it.

[@CuriousMarc]

It's from the Soyuz clock series, the Tetris song played on my Mac SE. Available on the Soyuz Clock web page: www.curiousmarc.com/computing/soyuz-clock-744h . It's become the intro song of my aerospace related videos.

[@MrKelaher]

wow I though ultra centrifuges made a scary noise :) And that slip ring on the test turntable - I thought 12 way was impressive, that is amazing.

[@ds3930]

I like gyros too. Arby’s has a few and they are “ok” but I have a Greek joint nearby that’s real good.

[@miikapekk5155]

Thank you Ideal Aerosmiths , I'll definitely consider buying your products sometime in the future. Without kind people like you we will be sitting in the dark ignorant about such wonderful devices.

[@twobob]

Extra marks for the descending Major cuts at the end ;) 'Musician Cap' doffed.

[@tasteslikeawesome]

I wish you could set up a simulation of a gimbal lock on the Apollo. I don’t know why I think it’s so cool...

[@Orbis92]

Was this filmed on a Vidicon? 360p only ;)

[@billchavez8473]

Nice scale at the end.

[@sbrunner69]

Good to see you are drinking quality "agua con gas" while performing these complex tasks!

[@davamig]

My Grandpa was a Naval expert, when the factory where he worked in the thirties of the past century, they put two giant gyros on a ship in order to stabilize it against waves roll…

[@ojkolsrud1]

Magnificent stuff! Gyros are quite fascinating! I have an experiment for you - let this run (not on the testing table) for an hour, and see if it picks up a drift of 15 degrees. You might guess what it confirms if it does!

[@CuriousMarc]

Earth rotation (360 deg in 24 hour is 15 deg per hour)! I wasn’t sure if these had sufficiently low drift for that or if this old gyro would be safe to operate for an hour! But you are right, I shall try.

[@ojkolsrud1]

@@CuriousMarc Yep!=) It's not a given that it's sensitive enough, but seeing at least how precise it was made me think about it. I've also seen other people on KZbin do that experiment with old gyros, which actually were that sensitive. Good point about letting it run for that long - don't stress it if you think it might not survive. I guess you could run it for 15 minutes and see if it drifts 3.75 degrees, or to the nearest marker and check against time.

[@stephenhedge2489]

@@CuriousMarc It is only a direction indicator. I worked on two Inertial Nav systems back in the '90's and tested them for drift over several hours at a time but did 100's of tests.

[@stevec00ps]

I love this!

[@AKAtheA]

can you strap a smartphone to table as well and show how its chaep IMU compares to a mech. gyro in terms of precision and drift?

[@Stebanoid]

an awesome toy you got!

[@SynaMax]

That gyro looks really similar to the Sperry gyro used as the AE-35 prop from 2001: A Space Odyssey!

[@Some_Beach]

IM HYPED

[@rpavlik1]

That gyro tester looks pretty cool. Was Huawei actually like calibrating or testing their phone gyros? Or is there some other telecom purpose for gyro testing? Neat to see how stable that old gyro still is. A lot more energetic than the mems ones, but it looks like you wouldn't have to integrate rate to get orientation, you just read it directly, which is awesome.

[@legobuildshq]

Awsome!

[@001snapshot]

Such interesting stuff..."as i have come to expect from this channel"....please explain Gumbel Lock?....also...hows the PS/2 coming along?

[@001snapshot]

srry...Gimbel Lock.

[@enilenis]

My father had access to industrial gyroscopes, when I was little. They were fascinating "toys". Very complex. Ideally they're silent. Noise means vibration and friction. Properly serviced gyroscopes are silent. Ones that use gas or vacuum are especially. These things are the atomic clocks of mechanics.

[@smeeself]

Once you have completed your project, how long do you envision it taking for the Apollo gyro to actually spin up to operational speed? Thanks.

[@S0N1Cua]

Have you checked the dial? Is it radioactive?

[@aaronr.9644]

pretty cool!

[@senilyDeluxe]

So how are the wow&flutter specs on that turntable? :-)