Failing To Build A Big Satellite Dish Rotor System

[@patchvonbraun]

That was a *tremendous success*, in that you learned what doesn't work, and what to work on. In iterative engineering, that's what I call a success!

[@prasah18]

True, in my profession there is 99% failure

[@Deja117]

Very true, he also built a (working? Kind of?) proof of concept. Nothing is ever perfect at the start, but we slowly learn to either work with the quirks of it, or to design a solution to solve it.

[@perpetual4958]

May I suggest the 'lineair drive pedestal' It was 20+ years ago I found it in the 1965 conference report from the large earth station antenna's conference in I believe Eindhoven, Holland. 8 lineair actuators. 4 pairs with a knee in between. This way one can track 180+ degrees in elevation and 360/continuous in Azimuth, absolutely gimble lock free. As for drives one can go old skool and get 1 phase, or even 3 phase actuators/motors, for low power control from old analog satellite receiver one can use a relay. TV antenna rotors are far too light load and have way too much slack in drive.

[@scottw.8614]

Okay.. I’m hooked . I am 64 years old. I hope to see this satellite tracking system come together before I’m dead and buried!😂. Keep the faith… Never give up.

[@EZCyclone]

I'm a few hours south of you and have a machine shop. I would be glad to go over some ideas, see what we could build. I used to build automated telescope mounts, but that was a million years ago now.

[@cherrymountains72]

You are a kind man. Thank you from the other side of the pond (a.k.a. Europe).

[@saveitforparts]

Interesting! I think KZbin got rid of direct messages and comment replies are always hard to find, but you can email me (gabe at saveitforparts dot com) if you want!

[@jeeper426]

most of figuring out experimental things like this is finding the thousands of ways that Don't work until you find that one handful of ways that it will work, reliably, and quickly deployable, i can't want to see how this turns out, it looks like a pretty sweet project

[@0000Sierra117]

My grandfather built an observatory in the backyard of the family home (he also built fences, sheds, and the majority of the house itself, he was a remarkably productive man) with a 10" objective and mounts to attach a camera. In addition, he built a star-tracking system running on a pair of Commodore 64s (I don't know if it needed both to run or just one...the software is long gone along with at least half the hardware for moving the scope itself) to point the telescope at objects of interest and take photos at specified times or long-exposure shots. This video on satellite tracking reminds me a lot of the wonder of being told about all this as a kid. Maybe a bit long winded or strange, but I mean that as praise, you remind me somewhat of the stories I heard of him and are one of my role models of the kind of tinker/maker I want to be. Thanks for putting this slice of yourself out there for us to see.

[@cherrymountains72]

On Commodore 64s, wow, your grandfather certainly was a remarkable man if he knew how to built physical structures *and* how to code a tracking-system on the C64. Colour me impressed. 👍

[@saveitforparts]

That's awesome! I'd love to do a big telescope one day.

[@lambo_drives]

8:32 (note from the past/future) great job installing that one way cat door 👍

[@Rouverius]

Written seven days before the video was posted.... what is this magic🤣

[@mrw1160]

​@@RouveriusCool radio time travel stuff.

[@patchvonbraun]

I had that same "Archer" rotator back in the 1980s for a 1 x 2 vertical Yagi array for working tropo and meteor into Vermont from my house in Ottawa. Back when I was both single and very well paid :) :)

[@RinoaL]

The multiple disciplines needed for this sort of thing is a real test of a tinkerer. I really enjoy watching your building method. I really hate when I have to start cutting things up and changing directions on a plan, but then when you give up and start over you tend to be a little smarter.

[@charliec154]

Fun video! - An idea - For a big cheap and powerful pan/tilt axis you could use an old moving head stage light. Something like a VariLite VL2000. Some of these ancient lights are getting too expensive to repair for hire houses and they sell / scrap them. You can usually communicate over DMX interface or drive the stepper motors yourself. Good luck!

[@rainer229]

I thought actually the same, that an old moving head would be perfekt. But don't know it it's strong enough.

[@BigDaddy-yp4mi]

So my family ran a satellite installation business and did well and was out before the digital revolution and cheap Chinese stuff killed the mom and pop electrical stores. The dishes they installed up to the late 90's were the BIG dishes and they still have TONS of equipment left over stored in a 6,000 sq.ft. shop on their property. I know for sure the linear worm-gear drives are still in there, some still in factory packaging. Tons of controllers as well. Can't give you all of it, but if there's a particular part or knowledge you need I have access to the parts and access to my family who knew that stuff inside and out. That group is older now but still cognitively sharp as a tack. Feel free to message me if you could use assistance. You seem like a worthy horse to back on a cool project! Either way, best of luck my dude!

[@saveitforparts]

That does sound interesting! I think YT got rid of direct messages, and it's hard to find comment replies, but you could email me (gabe at saveitforparts dotcom)!

[@moontravellerjul]

i also don't know how to produce a functional solution within your requirements, but the approach is fantastic. you know what the success criteria are and can identify the shortcomings of each implementation, to know what to change in the next iteration. super cool

[@drPeidos]

I don't think it was a failure. You discarded a bunch of cool ideas that you thought they could work but don't work. It was also fun to watch you try. Keep these "failure" videos coming.

[@MichaelOfRohan]

"I know what I want, I just dont know how to achieve it" That, my dear friend, is sacrefice.

[@jedharding3492]

Can't wait to see the next series of videos where satellite dishes get mounted on Tuggie, the speedboat and the handcar!!!

[@404DisasterNotFound]

Abe, water that plant tree thang! BtW, loving yr vids! Got myself a Bambu Lab A1 today. It's outa this world!!! Greetings from a Belgian, who lives in Poland :)

[@Jason-jb1tf]

I remember many years ago, 10 years or so? Travis Goodspeed did a talk at 30C3 called "Hillbilly tracking of low earth orbit" and it was so cool to see, that was my first introduction into at-home satellite tracking, and now it's cool to be watching your videos regularly and seeing all the cool things you're up to.

[@ChrisIsEditing]

"a project I've been putting off for a while" oh boy, here we go again...

[@TSGEnt]

7:12 I rmember as a kid my home back in the late 60s had the controller you have at the top of the screen. Black box, white dial, black rotary pointing knob. Wow what a vivid memory of that thing.

[@murraymadness4674]

A couple thoughts/ideas. An old cement mixer can often be found free or cheap and the old ones have a big 10:1 gear that spins them. Usually lots of slop though, but you could fix that in software if consistent slop. If you look on my channel, I built a very large cement mixer, and the last version shown uses an old wheelchair dc motor (I got wheelchair free) that can handle a lot of weight and torque. Also on the mixer, I used a front hub from a car (they are free all over) which can handle hundreds of pounds and are very tight bearings. I'd originally thought of using ebike hub motors and gears, but these are not really freely available, are not as good as the wheelchair motors that are heavier duty and geared up to move slowly. Another idea is not to use a pole and single pivot, but create another fixed larger dish under the one that moves and have like three rotating balls the dish can move on, so the weight is supported by those points, and then moving it around is just moving it not supporting its weight while moving it. Not sure if you get what I mean. You try to move it by rotating those points of contact, but that is getting too ambitious. A pair or three linear actuators or other motors that just pull a cable could then move it to point anywhere. This would be "expensive" way to do it, but not when you use junk parts. hope that helps, and look forward to seeing you getting it to work, enjoy your videos.

[@benjohan4]

An onstep system with some bigger stepper motors in alt/az could be interesting

[@michaellichter4091]

A very nice project, I would say it looks good for a start. These are not problems that can’t be solved; I think they could solve them. For example, one could save the positions of individual satellites and automatically align the satellite dish to those positions again. The geese also had something to say about the project. Thanks for the video.

[@LazloNQ]

I've used the ISS Detector app with plugins for years on my Android devices. I used velcro to attach the phone to the boom of a logarithmic antenna I built for amateur satellite work. It's as simple as matching the 2 dots on the app on top of each other in order to maintain a bearing on the passing satellite.

[@Teukka72]

Thinking out loud here, but a table like a huge "lazy Suzan" for N-E-S-W orientation, with A-frames and an axle on which the dish is center-mounted, driven by a worm gear to do elevation (+-90 deg).

[@garydion]

A fantastic, cheap, SUPER strong lazy susan can be made using a "hub assembly" meant for a car. Pro: you'll never have to worry about the stresses on it. Con: doesn't spin very easily due to the thick axle grease, but in this case I think it's desirable.

[@bikeforever2016]

Washing machines have strong and stable bearings 🤔

[@aserta]

15:08 make a swashplate type joint. It can be actuated from a separate position (than the joint itself) and they can be made with common garden variety stuff. Also, they are very strong. Some of them hold helicopters in the air after all. :)

[@JendrossekSip]

Hey Gabe, happy to see another attempt on the rotational dish. One day it will be a success. Enjoying to see the progress. Was just thinking you might find some info from hobby astronomers as they deal with the moving objects as well.

[@freidounzamani6791]

You can put your small sat tracker at the focal point of the large stationary dish looking into it. The big dish will project a small picture of the sky which the small tracker can cover.

[@ManMountainMetals]

Gotta learn to weld, brother. All kinds of things are possible then.❤

[@nedj10]

That bolt you are worried about bending should be a fixed welded support arm. Sounds like its time to put the spare parts down for a few minutes and practice the welding you mentioned. :D

[@alzeNL]

I cant say how much I geninuely love this channel / Gabe - hes is so amazing and I really enjoy everything you do - this work is such a briliant example of what inventors/researchers go thru in real life. seeing the honesty and methods is like a 'living journal' . Gabe, you are a real hero to me mate and thank you for your amazing work. I can see you in 2034 doing 'so i'm going to recreate a early SpaceX rocket with parts from axman' :D

[@lambo_drives]

Present, note: A set of specific, on-demand/order pledges of either: “I Support Satellites” T shirts or stickers with funds going to the motorized mechanism in furtherance of education. 🤷

[@seabeepirate]

I meant to comment this the first time I watched the video but oh well, here it is anyway. Hoverboards are easily sourced and have two strong BLDCs. You might even be able to tap into the encoder circuit to drive it with an Arduino or Pi so you don’t have to buy or build a power supply and it could run on LiPos.

[@XionUnjust]

Zane Zaminski would be so proud 😅 I learned so much from this video. Keep it up man. I love your work. I do a lot of reading and watching videos about space in the universe and the scale that you showed with 3 ft from the globe for a geostationary satellite compared to 300 ft for one of the spacelink satellites is crazy. Thank you so much for that visual reference

[@therezinUK]

I would 100% wear a "made of scrap metal and compromises" T-shirt.

[@AddieDirectsTV]

You need to take one of those PTZ and beef up the motors. I believe that is what the pro ones are. I’m off this week so I can’t go peek at the big dishes at the station. You might also need counter weights.

[@TheWinning247]

When I started looking into making a radio telescope, I came to the same conclusion, that a telescope mount (polar) was just too expensive. If you can get hold of a big disco light/moving head, they have the Axies already set up and motorised. All you gotta figure out is how to mount the dish.

[@gogglet72]

Love this project and the channel save it for parts and amature radio go hand in hand. Carnt wait for part 2. Good luck.

[@webluke]

You can get bed frames for stuff like this for cheap or free angle iron. It also looks like the linear actuator is upside down. One end looks like it could go on a pole mount clamp, and the other through an eye bolt for a stronger mount.

[@kd5inm]

You need a top section of a tower with a couple of plates inside the tower. One hilds the rotor and the other is for a rotator bearing that holds the load. Then put the actuator up at top to make it go up and down.

[@PU7MZD]

The building montages are one of the best things about your channel, I really love thoss

[@thealeas]

Thank you for testing those ideas. I actually was thinking of using a rotor like that but I see it would have failed.

[@banellone]

If you need to slow down fast actuator, just lower the voltage. Works for me, 24V actuator supplied by 12Volts.

[@TechGorilla1987]

@11:37 - The hokey build montage with Art Bell-esq music is top notch, man!

[@devinsullivan6160]

Welcome to the ultimate sciences Gabe. 😎 it's not fun, but when you get it right, it's fun, very fun

[@sameckert]

I'm stuck on this same project. So far I built a nice PoE powered one with feedback on the motors and network and serial based input options, but I'm stuck at the enclosure part. I need to come up with a fairly weatherproof enclosure. I keep thinking sideways rain and get nowhere. I think you have a little more than you think you do. You just need to control both of those motors a little better. If you have a bench supply you can play around with the current and voltage to find a slower operating speed that doesn't overheat them. You may want to shift to a pulse based control. You can do that with a dual H-bridge. Honestly you can drive both with one and a microcontroller. The AC rotor could be slowed by changing the frequency you send from the H-bridge. As for all of the runout, you can try to mechanically tie the pivots with something flexible to force them to favor a direction that can be overcome by the motor.

[@johnr1927]

tracking dish different animal shore up your mount big time ( bolt it to garage ) peak your dish first on a stationary and stow it in bad weather good job gabe😉

[@budgetgentleman1606]

Success or failure, I’m confident we are all learning stuff so keep up the great work!

[@reynoldsair]

How about using a couple of drills mounted perpendicular to each other? The drills turn screws pushing and pulling in the AZ/EL. Seems like most drill motors are variable speed as well. After you figure that bit out, then you’ve got to figure out how to send the drills electricity based on signal strength in order to track.

[@Gu1tarJohn]

Yes! T-shirt about scrap metal and compromises!

[@paulshields1883]

Aberrant torque can be minimized with counterweights, which you have, but heavier weights needed to put the centre of mass in the right place. Bicycle parts are cheap. The larger the bearing ring, the more stable. Stiffness is improved on poles having larger diameter. You might want to control the beam width, and zero in to focus on the sat as you move to it

[@rkirke1]

Auto wreckers/caryards might be a good option here? For the azimuth rotation I'm imagining an auto transmission flex plate (a dinner plate sized flat metal gear with teeth all around the edge that the starter motor engages with). Instead of driving it with the starter motor, drive it with a power window motor. These are already geared down and are 12V brushed DC motors (direction is controllable by polarity - you can use an R/C or Arduino H bridge module or DPDT switch). I've used them by themselves before to rotate antennas and they're plenty strong, but a bit too fast. With the additional reduction from driving the flex plate I think it'd be pretty ideal. Not sure what car scrapyards are like where you are, but here in Australia if you go when they're not busy and explain what you're doing with a project, someone will often take an interest in the 'mad science' and be happy to spend some time rifling through different crates to find bits that will work. Since the exact make and model of car a part came from doesn't matter at all to you as long as "thing fits in other thing", it's a plus for them too as they can get rid of parts that are not in demand and wasting space.

Get a used Electrical Power-Steering thing and drive the input using a mid sized servo or something. They got tons of torque and you could build a linkage to get it to move the azimuth.

[@JamesHalfHorse]

The rotors generally work with a thrust bearing. The antenna or dish in this case would have all its weight resting on that leaving the rotor only needing to deal with turning it. Think that and steppers might get you there. Also Ali has some really cheap screw jacks as well that I am considering for a project that might work for you as well 30ish dollars each.

[@ace_life7079]

I think it was a great video As with all your videos, The viewer is kind of on the edge of Is thier seat on whether or not the things gonna work, that's what's really delightful about the save it for parts channel. You don't really know until the very end. Whether it's a success or a 1/2 failure. Or a total failure either way it goes. It's fun. Thank you so much for taking the time to share your life with us. Please do not stop creating this content so that we may enjoy it for the rest of our lives.

[@user-ej1ds5eq2n]

if you could find....2 old screw type Garage door openers....from 70's, you could solve jerkiness, accuracy and strength problems...add stepper type motors...to drive screws.

[@pointlesstinkering]

I'd forget phone-apps for tracking sats (especially geo-stationary ones), what you need is an as wide-band as possible SDR, and just move the dish around until you see signals show up. I've had the most success doing just that. Keep it simple. :) I have a similar sized solid metal dish and i used an off-the-shelf cheap tv rotor (they do still make them!) + actuator for vertical, and even though you'd think it'd be extremely under-powered, it actually works, kinda! The only issue is that when you stop rotating, there is some 'bounce' so you sometimes have to nudge it a bit until it comes to rest in the position you want. Getting rid of the bounce is really where the bigger motors help, but even with a small motor you can still make it work. For fast-moving LEO passes, use something like gpredict to automatically drive the dish pointing (but now you have a completely new problem: how do you accurately know if the dish is pointing where gpredict thinks it's pointing ;) ) Also, I saw in one of your other videos you picked up a few DVB-S2 sat. decoders and you didn't know what to do with them... Here's a useful trick: You use them to drive off-the-shelf LNB's (like the outernet one you have!) -- but then you also hook up a splitter, and a bias voltage module in reverse to remove the bias voltage, and then put the other end of that in an SDR. Now you can use generic LNA's with your SDR, and have a way to send the needed control voltages to the LNA to switch between high/low band and H/V polarization, without having to build anything fancy, using literally junk! :) The universal LNA's usually have written on them the input/output frequency ranges, and the LO offset. You can stick that offset in your sdr software and get the exact right frequency reading in your waterfall. Wide-band sdr's for sat. stuff is the most useful thing to have, the more spectrum you can see at once the better- makes it so much easier to find signals. Out side of some narrow-band telemetry stuff, most are relatively wide-band anyway. And if you can do the pointing from the comfort of your lazy desk chair while staring at a waterfall, that makes everything so, so much more easy. - It's worth it, so persist in getting this working! :)

[@haxwithaxe]

Have you seen the radio telescopes that have a horizontal rotation and a 45deg off horizontal rotation? You can put a worm gear on big gears on both axis and you can use relatively weak motors to slowly turn each.

[@karcinogen]

Great video as always, showing us the trial and error part is a lot better than half the other channels who just show the project completed with little explanation on how it was done. Now you got me wanting to make my 11m base antenna better..haha cheers!

[@richardvanasse9287]

I wonder if you built a motorized dobsonian style mount where the whole base swiveled like a turn table. I think some people build such things out of plywood with plastic laminate for the bearings. Add a couple of surplus servo motors for the axis. Might work. 🤷🏻‍♂️

[@chriscaptain3141]

Keep on working, want a good result ❤❤❤

[@nrdesign1991]

For the Azimuth you could try a bearing or turntable on the ground allowing the base to rotate, a pole sticking up to hold the dish, a pole sticking out to the side and a drive wheel on the end of that which drives on the ground with a geared motor. Gives you the advantage of the long lever for torque. The linear actuator would still work under lower voltage if it basically won't have to lift anything with those counterweights. Try balancing the system out so the linear actuator basically just causes the movement to happen but not to lift much weight. You could try a current limited lab supply for soft-starting.

[@ipullstuffapart]

It's beginning to seem like it may be easier trying to stop the satellites from moving, or move the entire earth to keep up with them. For more practical advice on the cheap. For elevation you could potentially use a winch to pull either side of the dish (or a lever/bar structure) to give some mechanical advantage, instead of trying to apply massive torque at the pivot. This would also be quite stable and provide some triangulation to the structure.

[@Mosfet510]

Some of those names are a blast from the past! Good video 👍

[@M1les_Grey]

Hey there! I’m not sure is you remember but a few months ago I commented on your video about the pelco mounts. I have actually successfully retrofitted mine with stepper motors and an arduino and it is currently able to move a 1.5 meter solid dish. Better yet it is using the same model that you used for your smaller pan tilt mount. If you’d like some info as to how I did this let me know by sending a dm and I can send you some videos and info on it!

[@saveitforparts]

Interesting! I think YT got rid of DMs but I found your email :-)

[@moormoor4281]

Thanking you most kindly from English England

[@JonnyWaldes]

Gabe maybe solar panel "sun trackers" or techniques can be repurposed? In general worm gear motors are super strong for applications with a lot of torque!

[@ezjenken]

Put an outer ring on the dish itself, and mount the ring to a goal post shaped stand with pivot points, this way it's balanced and won't bounce

[@jameskelly1680]

I love your montage music. Can I make a suggestion? Your dish wobbles around quite a bit because the base isn't stiff. If you can put in a fence post or a little concrete with a pipe sticking out, you will have better results. We've put in quite a few C-Band dishes over the decades, and you really would not believe how much concrete you need for a 6+ foot dish. It really adds to the stability of the whole system because it eliminates lurching and jerking. I really like your idea of having one dish that is set up to be able to move around and track the whole sky. Having a known good install would allow you to do troubleshooting one step at a time. This would be the first step of a known good install. Even just a post hole with a 90 pound bag of concrete in it would be something. If I might make another suggestion, can you use PWM to slow down the dish motors? This would give you a lot finer control of movement. You may need stronger motors for a dish that size, maybe stepper motors on a large threaded rod. These need to be WAY slower. Or maybe gear them down.

[@dagmarsuarez3033]

Gabe, I looked at what you were trying to do and had immediate thoughts, many of them based on flashbacks from things that went So Badly Wrong with the robotics team's creations over the years. What I think you need are some serious chain and sprocket systems with #35 chain and plenty of crank on the chain tensioners. Oh, also rotation sensors. And speed controllers. Your ethos naturally is diverting things from the waste stream - and lets be honest, Axman is often the last quiet pool before it tumbles over a waterfall into the landfills - but if you are willing to consider other cheap-ish to free stuff, well we have this sort of thing. Shame I ditched the giant worm-gear box that we got from McMaster a few years back, but I don't have enough space in my own Area 51 to preserve all the Ancient Relics. Anyway, you know how to get in touch. BTW, just reached out to a guy who makes fake deer for the DNR. Yes, fake deer that robotically move their gigantic be-antlered noggins to tempt poachers. I think our mechanical and programming kids could up his game appreciably. Many of them are hunters too...... Badger Trowelsworthy over in Wisconsin. (An easy trip over btw....) facebook.com/avisautomata

[@saveitforparts]

Robot deer sound amazing! I'll have to do some more thinking on how I want to try the satellite positioner stuff.

[@michaelterrell]

Those TV rotors use a run capacitor . They were a high failure rate when I used to service them. That first TV rotor looked like a Channelmaster, which was also sold as Radio Shack. Alliance was my preferred brand CDE made heavier duty for Ham antennas but even used they are expensive. The speed of the linear actuation depends on the DC voltage .

[@stanallred5184]

tek 2000 has slew drives for yur big dish and also dual axxis actuators a 6 inch for up and down anf also for azimuth and a feed actuator

[@UncleBildo]

Uncovered old CB radio stuff here this week, you'd have liked part of it. Old beam antenna, somewhere the rotor for it has to be, and control box. Probably with the actual radios on a top back shelf somewhere. When I was a kid, the folks co-founded a CB club that was pretty popular for a while. We had some good gear. Should be a President Washington radio with a built in bi-linear in the pile of radios. Might have to drag some of that stuff back out to put to use. Wonder how noisy the radios are these days, it was pretty brutal last time I turned one on!

[@saveitforparts]

Last few times I've listened to CB it's all guys in Florida and California yelling at eachother on giant amps 😂

[@54RKY]

​​@@saveitforparts I'm picking up a.m. CB dx from Louisiana and other places in America, occasionally patchy but clear as a bell in places, lots of shouting and strange stuff. 😂😂 I'm in uk

[@brucebaxter6923]

When I was a young fella, 32vac was for lead lights etc. 32vac transformers were in the 24vdc supply.

[@robertgast5953]

look in to driving the linear actuator with pwm using an Arduino or something similar, this will allow you to control the speed

[@LazloNQ]

If you don't mind a little welding, how about use bicycle parts...chains and sprockets can be mish mashed up to create whatever ratios you want and then you can use servo motors to spin a small sprockets to create incremental steps on the large sprockets mounted to the dish actuators. As far as keeping the wobbles to a minimum, actual satellite mounts have to be really robust...like big steel pipe embedded in concrete. If you wanted to create a simpler robust mount, you can use chain link fence top rail ends and cut the top rail to length. Gives you a boltable end on the toprail.

[@rockyewelljr9781]

u could look into telescope mounts for large and heavy scopes they use stepper motors and few drivers and voltager regulators can be made from almost scratch or most parts per built and only some assembly cloudy nights has a column about diy trackers

[@fotografm]

I think your beard grew during that video 🙂 Great to see the process of how you will arrive at a successful setup !

[@NeilHoward]

It is great watching your thought process :)

[@RedBear345]

I think you should seek collaboration with a KZbin machinist. I wouldn't be surprised to find that you have already investigated that route, but It felt right to mention it. Perhaps "This Old Tony" would be interested? Specifically, I think some of your actuator attachment points, and general COG concerns would be well-addressed by some machined custom bracketry. Best of Luck, just the same. Thank you for sharing your failures. I's argue they are of more value than successes.

[@caseyjones1999]

Neat projects! Have you thought about using a trailer axle and hub for the pan? And for the tilt some pillow block bearings? This is coming from some solar tracking array experiences

[@rafaeldiegonavarro]

Bro you need closed loop stepper motors with micro stepping . Steppers are crazy precise

[@danielr82]

The pole wobbles - brace the pole to the cross base. use U bolts, the same as used to attach the motor to the pole.

[@sgath92]

About getting old timey antenna rotors operational again: Most 1950s to 1990s designs used two identical motors, one in the rotor housing and one in the control unit. The circuit keeps both motors in sync with each other. Which means to restore one of these kits you can buy a second control unit on eBay to steal the motor out of it, should the motor go bad in either your control unit OR the rotor assembly. The gearing for most of these can be found in stl format online and printed in nylon via a filament 3d printer. The main failure point of these kits even when new is they have a ~27 uf capacitor in the control unit that liked to go bad. The gears in both units are also plastic and break apart after many decades and/or are coated in grease that can harden up. Replace the gears, relubricate the gears, and replace that control unit capacitor and 90% of the time you'll be good to go for another 50-70 years! The controller units also had micro switches that could fail but you can replace those with a cheap toggle switch if you don't care if they look modified. The rotor units are the rarest parts of these kits to find because most got thrown out during chimney/roof renovations after the homeowner switched to cable tv in the 70s-00s. The control units tended to survive and are very plentiful even today on eBay and other sources (some people buy them just as trendy mid-century-modern house decor). Now the exception to all of this is there were some systems were the controller unit was basically a rip-off of a ford fuel gauge re-labeled as N S E W, with a fuel sending unit built into the controller to tell you how your antenna was currently positioned with two simple buttons to tell the rotor to move one direction or the other.... the dead give away that you have something like this is that the controller will be tiny and light weight. The two-motor system is what you want.

[@sgath92]

Also most 4 wire systems are interchangeable as far as controllers & rotors go, so I bought a cheapo 1990s radioshack kit and set it up with a restored 1950s controller for a more vintage look inside the house. I forget exactly what specs that one capacitor has but it will set you back like $10 for a replacement.

[@sgath92]

Post-Scrip#2- this basic synchronized motor circuit was a rip off of what the US Navy used in WW2 to remotely-control battleship gun turrets.

[@toddanonymous5295]

If you could find an MP-61 pedestal from a surplus SCR-584 radar system, you would have it made. Good luck as I have wanted one since the 1970's

[@s57rw]

Trying to find an AZ/EL ham radio rotator even used will be pricy. Apart you get from some garage sell where somebody doesn't know what is acctually selling. But for tracking LEO sats with a large dish I'm affraid even for example the Yaesu G5500 won't be accurate enough and also not designed to support heavy load on one side without modifications. On X, Ku bands with large dish if you are few deg off could lead to not receive much. As some sugested bellow you can make it using bicycle sprokets, various gears and bearings. A smaller car differential can be also useful for the azimut part. Most of this part can be found at junk yards. Driving motors don't really need to be powerful since you need to do a great reduction in speed. You can use motors and gears from rotators you already have and further reduce speed and increase torque using additional heavier gears or bicycle parts. If the motor doesn't have a break you can use a worm gear for last transmission stage so wind or gravity won't move the dish. Horizontal and elevation shafts must be fixed with bearings to prevent stress on the rotator and make all sturdy. When tracking to avoid moving and stopping the dish constantly because would be wobbling due play between gears and its momentum. Best to match tracking speed with angular speed of the tracked SAT. This can be achieved by controlling the speed with PWM. Position feedback can be red from a potentioneter rotating together with the shaft. For good accuracy also a capacitive rotary encoder from a cheap digital protractor/angle ruler can be used. Some I've disassembled had pins on PCB for serial data output and were easy to read with a microcontroller. One consideration for tracking LEO SATs. If possible would make to have elevation of all 180 deg (horizon to horizon). With linear actuator you can't get 180 deg. In cases you have an exact or close to overhead pass having only elevation to 90 deg you will lose some of the overhead pass. When reaching 90 deg of EL you will have to rotate AZ by 180 deg to track the SAT again and this takes some time. By having horizon to horizon feature you don't run in this problem. Using 2 motors with gearbox found on hamfest flea market, some additional gears to further reduce the speed, bearings and some steel which most found at junk yards have made my AZ/EL rotator for ham LEO SAT and is heavy duty enough. Since used only for rotating 2m and 70cm yagi antennas didn't bother to make the tracking accurate to a degree. Such antennas have beam width that 10 deg off doesn't make any difference. But could improve if required by installing more accurate position feedback and adapting the ESP32 code. Mechanical part would do with no mods. And for last it would make all the construction easier if you learn welding. I managed to put together all mechanical parts by weling and other basic tools like drill press, angle grinder, file, hamer, hack saw etc. Nothing advanced was used. Just as with all my projects it took me quite some time with several failures in design, modifications... But for that the angle grinder comes handy to cut a wrongly designed part and reweld a new one 🙂 Wish you good luck and fun by putting the rotator system together 😁

[@DadofScience]

I feel like this is a project I could also take on and fail with similarly or perhaps even a greater failure. If only the supply of parts you have access to I did too. I think I'd have to build most of the actuators from scratch, likely driven by something like treadmill motors.

[@Hamradio2024]

I wish i could get an old EGIS rotator... thats the top of the line

[@shawnwilliams6306]

The thing you couldn't identify and then cut in half is the base of a military tilt up mast kit. It would have come in a big rucksack with sections of poles you can slide together to make an antenna mast. The 4 holes in the corners are for big steel spikes you'd drive in the ground to anchor it.

[@TotalKeyOz]

A thrust bearing above the vertical rotor would be good to reduce the load on the rotor since the bearings in the rotor will not be able to withstand this in the long run.

[@burprobrox9134]

That cat is nebby and didn’t want you to be there Lol

[@benmmaddog]

wonder if making a soft start circuit so there isn't that jolt at start or maybe for the linear using some sort of PWM to give you better speed control ?

[@vjnobody]

Fun idea, and you're getting places on it :) a friend showed me a setup he was able to tune into rando sat broadcast from around the world with an inexpensive connection to a PC :D I'm a bit of a tinkerer myself, what about a microwave rotisserie? Comes in every microwave :D maybe not that strong OTOH... how about re-purposing an old drill to spin it?

[@Fluxiton]

I would try to 3d print the pivot and turret with bearings so it runs smooth without wibble wobbles, a good storm will break it but would work as a proof of concept. I would mount the linear thing on the weight side, I think the weight on a pole will cause wobble and switching the mount to it might stableise it. I would use a belt around the turret part and then drive it from whatever motor was handy. Dunno if any of that is smart but thats what I would try.

[@deftnerd]

Because of the heavy weight, everything you're going to be working with will require a lot of torque, which means big and tough (and often expensive) components. Another problem is that strong motors trade torque for precision. You can often use a series of small and large wheels with cogs to change the speed of motors into slower speeds with more torque... If there is too much torque the cogs could break, but you could just take a lot of parts from bicycles and use a chain drive, so the pressures are spread out across multiple cogs. Lots of bikes are just thrown away too. You would probably have to break out the welding equipment and angle grinder, but with a few sacrificial dumpster bikes, you could make a frame that holds the dish and lets you use pedals to adjust the directions pretty well... and then hook up motors to the pedals once you get the mechanics worked out. For feedback, there are many arduino and esp32 based microcontroller add-ons to measure angles, so you can use something with those to give feedback to make sure the dish tracking is precise.

[@michaele.milionis5039]

Sick montage. I enjoy your content. Keep up the good work.

[@TheTarrMan]

I used to be a dish installer and those reflectors had to be really accurate to reflect the beam just right. Quite often repair jobs involved damaged reflectors and they'd look totally fine but it's a yard mount and they accidentally got hit by a bad storm or the lawnmower or whatever so we'd replace it and no biggie. Problem is those dishes we used were designed to capture multiple satellites at the same time, it's a really delicate precise oval geometry and the slightest kink will mess it up. My question (because I still know nothing about this because I'm trying to learn too) are you sure you're LNB is focused within the dish and not just by measurement by tape measure or whatever? Like an actual measurement?. . . We had these thingies we could test the LNB's with and on the ones that got the reflector warped we could literally just lightly push or pull on one side of the dish and our satellites that we're trying to aim at would phasing in and out of signal strength from right to left depending if it's the two satellites for the "eastern arc" or the three satellites for the "western arc". The whole thing looks like it's flexing around way too but maybe there's still optimal spot in there if you can measure it somehow..

[@RokasVtech]

Time to learn welding. That needs a stable - nonwobbly foundation :D - Finding rusty mettal , geting the rust off whit DIY sand blaster could be cheaper then buying random parts for lego construction. just add counterweight at the oposite end of the dish to move the center weight. - Linear actuator could be slowed maybe by playing whit the voltage. - As for motors , something like pulley gear belt system prob is the answer for horizontal movement. (again would require welding and bearings that are not cheap) What can one forshadow is that If its not stable enough Wind/storm could brake it completely.

[@SteveWrightNZ]

I've looked at the same problem from the ham radio perspective for a few years. I stopped work on it because there basically isnt any ham radio content on microwave bands at all, and I wsnt interested if I couldn't transmit. The other reason I stopped work on it is the same issue you're facing - dish calibration. Try a simple test yourself with just a compass - take bearings off maps and try find distant terrestrial items using that heading a simple compass, and you'll find the process so insanely fraught with problems to be unusable - same goes for pointing a dish. The only solution I can see is to calibrate out the problems with an AI bot steering the rotator and some sort of simple optical light sensor pointed at the moon at night, and leave AI to make the calibration tables for the rotator for you. After a few weeks or months of training maybe you will be able to some sort of calibration table for most of the rotator angles, and only after that the system should be able to point anywhere you like with accuracy of a degree or so. That would be a hell of a stunt however - impossible just a few years ago.

[@MrBtcruiser]

I thought about working EME at one point in my life, but the whole antenna positioning thing scared this mechanically challenged person away...

[@alexmacdiver]

Disability Hoist for Car. . . . . Some of these are powerful...... And Torquéà . . . . . . ( or tilting Bed/Recliner motor ) Or Engineers rotary table, like. ideal-aerosmith The 1310 series: Manual Tilt & Turn Tables are designed for precision calibration of gyroscopic instruments or any devices requiring a tilt input in one or two axes.

[@paulladdie1026]

drive the linear actuator, at a lower voltage, that will slow it down, or possible pulse the dc voltage, to moderate the duty cycle?