Building a magnetron attempt 2

[@thesciencefurry]

As a special gift for reaching 4K subscribers this video is now available in 4K. Just kidding xD Idk if anyone actually watches it like that. But thank you very much for reaching this milestone.

[@AaronLyNxAI]

You may have been joking but I've never seen a video with the option for 2160p so you truly are giving great quality. For my device that's almost overkill since I usually watch on my phone and while it can render that it's not giving me extra information. Where it really shines is when I watch on my laptop (16:9 aspect at 1920p) or my TV (been too long and don't remember 😂)

[@alphaindustries5775]

bro is the chad irl

[@thesciencefurry]

@@alphaindustries5775 If only I had at least a bit of the muscle mass lol. Because I'm slightly underweight 😅

[@albinjd]

Ive got some advice for ya, Firstly you want a deeper vacuum for a greater emission current. A Turbomolecular pump is probably out of your price range so i would try a few things to get the most from what youve got, Heat the tube up, while cooling the stem that feeds to the vacuum down. glass doesnt conduct heat well so you can create a huge differential across the tube. cool it with a Peltier cooling plate or upside-down air duster can. heat it with a hot plate or something. you could also put a wad of steel wool in the stem to trap more gas. this will also maintain the cool temperature better. Also, limit the length of whatever flexible tubing youre using because it will limit your ultimate pressure. best to use something metal, a KF bellows hose is best with a CAJON UltraTorr fitting on the end to connect to glass. make sure to get a vent valve and connect the bellows, valve and Ultratorr fitting to a KF 16 size Tee and youll have a nice part to make more of these in the future.

[@thesciencefurry]

@@albinjd I already do a few things you mentioned. I have a kf bellow hose and I'm heating up the tube. I don't really want to put anything inside the stem because stuff could fall in the pump also wouldn't that restrict the flow? The cooling seems a good idea haven't done that yet

[@aleksadjokic4115]

Nice video! Few comment: 1) Be aware of the space charge effect! The geometry and distance of the cathode to anode is very important! It can cause a space charge effect, your emission will be very low. 2) When dealing with small filaments, a better method of coating is electrophoresis, basically use the same what you had with NC and Acetone, only apply a high voltage(many patents out there). Or, if you want something that is even simpler, use a airbrush to coat the filaments, again the same NC and acetone. I personally use Amyl acetate and NC. 3) Invest in a turbo pump and evaporable getters(SAES). Small turbovac 50 shouldnt be expensive, and you can get down to -7mBar after baking. 4) Gas is your biggest enemy, keep the tube nice and hot while pumping it, it must be clean! 5) If you have a good spot welder you dont need to weld everything with nickel ferrule, direct metal on metal works, maybe not for a long time, but it works. 6) Use thicker tungsten wire, easier to work with and better structural support! 7) When burning the NC, it should be done in air, heat gun works good, 400c is enough, dont go below 350c. In vacuum, carbon is very difficult to remove. Hope something helps!

[@thesciencefurry]

@@aleksadjokic4115 I definitely want a turbo pump. But I don't have the money yet. Burning the coating in air is new to me. As far as I know the carbonate will be converted into oxide and that reacts with moisture in the air to form hydroxide which is allegedly a bad electron emitter (and I think it would poison the vacuum with water vapor when it decomposes. So I feel like I would have to heat the filament up on the pump anyways to drive that off)

[@nileblack]

4:25 maybe the flame got into the tube and whatever fuel it's burning on ( butane for example deposits junk) let the faint brown stain on the side if the glass?

[@thesciencefurry]

Could be. I had tons of water vapor inside from the flame.

[@TheAlchaemist]

@@thesciencefurry I assume you use methane, right?

[@thesciencefurry]

@@TheAlchaemist No, Propane/Butane mix

[@TheAlchaemist]

@@thesciencefurry ahh I see, that's it then. The higher the mass, the more chances you have to end up with carbon depositing, it may even deposit and cause issues in the glass joints/seals. We used methane, just straight from the natural gas pipe. With oxygen obviously.

[@thesciencefurry]

@@TheAlchaemist I always used it and never had problems with it before.

[@steve-h7z]

Could you try making a sodium + cadmium arc lamp? 😃

[@janno288]

Good luck with it, i am excited about the coating method. I think a diode tube or tubes to confirm that everything works would be beneficial before 'wasting' time on a triode or magnetron etc. Thank you

[@doityourself3293]

As a person that works with real magnetrons. You can't use the filament as a cathode because you draw current through it and it heats up the filament and burns it out if you don't regulate the current some how. If you do use it as a cathode you only put enough power in to warm it up and get it running. Other wise you have to put in a tungsten real cathode around it. Remember pulling current out of the cathode is power and that heats up the filament. Welcome to the tube world. You need to read an old RCA tube manual on tubes. Best of luck...!

[@analogsergal]

cheekbone jumpscare

[@MrSupro]

You can purchase ready made emission coatings from the Transene company in Danvers Mass. you can also use plain barium carbonate with a butyl acetate/butyl alcohol binder and vehicle. It will not decompose to the brown contamination you have there. You should also etch the tungsten before coating it. I do it by lightly oxidizing it by heating in air then firing in a hydrogen gas environment. If you don’t have the setup for that you can dip the oxidized tungsten in a mixture of hydrogen peroxide and ammonia for a few minutes. This will leave a clean etched surface that the paste will better adhere to. Also bring the filament temp up slowly. Use a ballast resistor of a couple ohms and watch the current. Slowly bring to red heat then continue up to orange heat for a few moments to flash off binder and convert the carbonates to oxides then reduce to red heat for use. Also titanium getters will not be sufficient to get you to a low enough order vacuum using only a mechanical pump. You will need a evaporable barium getter for that. They are hard to get in small quantities but I can help you if you need. You will also need a small induction heater to flash them. The 1KW eBay ZVS induction heater kits work fine if you make a smaller coil.

[@thesciencefurry]

@@MrSupro Thx for the advice. The titanium seems to work good enough. I was able to keep a good enough vacuum in my x ray tube up until now. I think I found something avout the effectiveness of different getters and this was acceptable. The active getters can't be kept in air for a long time so it's not the best for these at home tubes.

[@lucianioanpapadopol9401]

Hello Sir. Your videos are quite interesting! I've tried from time to time to work with glass too, for some reason it breaks all the time I let it cool or after is cool, when I reheat it do do some other work on it. How did you manage to keep your glassware intact while working on it? I've used Pyrex stuff prom Amazon but maybe it's not real borosilicate???

[@thesciencefurry]

It definitely needs to be borosilicate. If you have large pieces you might run into problems aswell. But boro should actually be pretty easy to work with and can be somewhat annealed with just the torch.

[@beamer.electronics]

Great exploration, well done.

[@christopherleubner6633]

Try making one with a ring resonator inside. Take copper and make a ring of it. Put inside 6 notched plates equally spaced then grind a notch in every other one then do the same in a mirtor image at the bottom. Next braze coper wire to the plates with it going throgh the gaps. To one of the wires attach a thicker wire to it as your antenna, and attach the HV feed to the ring. Plate the works with silver. Prep a filament with barium oxide and thorium oxide and mount in the center. Seal into a tube as usual and put magnets that fit around it in an axial field. Its ok to use an electromagnet. Make sure that all the wires going to the device are isolated with chokes to prevent the RF from backfeeding into the supply and magnet current leads. The resonant frequency is determined by the capacitance and inductance provided by the ring wires and the plate slots, the gain factor is going to depend on how consistant the LC is and the strength of the magnetic field. Have fun. ❤

[@nejcjug7135]

Could you try to build Photo multiplier tube ?

[@thesciencefurry]

Sheesh, that's so complicated. I still need to activate the one I have.

[@kaboooom2000uk]

You look great my freind do not worry. I am very interested in this project and your construction methods. The thing im quite interested in is what level of vaccum are you running and your setup for the vaccum.

[@zillboop4687]

Science! UwU OwO and oh my 😊

[@slyfoxchemistry]

Amazing video well done

[@thesciencefurry]

wtf I just published it a few seconds ago xD Thx

[@FurryAnimator]

that was fast!

[@slyfoxchemistry]

@@thesciencefurry but anyhow truely well done you have given me a idea

[@slyfoxchemistry]

@@thesciencefurry and fyi videos are set to fast as I am in class

[@FriesOfTheDead]

Great video! :3

[@thesciencefurry]

Thx :3

[@FurryAnimator]

you have all my respect, amazing skill! ❤❤

[@Emmanuel99966]

I think that you don't have to get the filament so hot that it starts to vaporize.I have seen many power tubes have an emission current of almost an amp barely getting the filament to its max temperature. bytheway what voltage are you using across the filament and across the tube

[@thesciencefurry]

@@Emmanuel99966 I didn't measure it directly but I tried a couple kV up to probably 20-30kV. I had to put 1,6 amps trough it to get the mentioned emission of 50 microamps

[@Emmanuel99966]

@@thesciencefurry anyways love ur channel , keep it up .hope it grows alot 😃

[@TheChillieboo]

this is sick!!!! awesome work!

[@ZecaSamicas]

This channel is pretty interesting not gonna lie Just out of curiosity, I'll get along with the new upcoming updates about this project :7

[@lasersbee]

Congrats on your 4K milestone...

[@Fluffberymoff]

as someone who likes science and furries also, you just earned a new subscriber! Edit: (I've been a subscriber for a long time actually)

[@ggarber4763]

I'm not sure how to ask this. Once the filament is up to temperature, is there a lower limit on the current or voltage needed to generate some microwaves? I have a microwave oven magnetron that I would like to experiment with but initially at very low power, maybe a watt or or so. Also is it possible to change the frequency without changing the tube?

[@thesciencefurry]

As far as I know there is only a voltage limit, the voltage needs to be correct for the magnetic field. And speaking of magnetic field. If I remember correctly you can change the frequency somewhat with it. But it's mainly determined by the geometry of the cavities.

[@delphicdescant]

I used to have some projects on the back burner that used microwave oven magnetrons. I became less enthusiastic about them when I read how many people deanimate themselves accidentally with those kinds of projects.

[@thesciencefurry]

@@delphicdescant Yeah, they are no joke. I used to play with them when I was a teenager and some time after, the eye doctor said he spotted something in my cornea. This was probably not related because I always kept a safe distance. And nothing was actually done about it after they took a closer look. But it scared the crap out of me.

[@ggarber4763]

@@delphicdescant I shocked myself so many times as a kid I'm jumpy as hell around electricity. Never got zapped by a MOT, but gutting the microwave oven I used about 2 meters of electrical conduit as my chicken stick to make sure the capacitor was discharged. Not sure I earn bragging rights for longest chicken stick.

[@elementaldraco]

If you haven't already found it there is a KZbin channel called Glasslinger. This person has full videos of hand making tubes and talks through the whole process and materials. You may find it of interest.

[@hiroshrosh3535]

hell yea, new channel to sub to

[@crimester]

you look like oppenheimer's distant cousin also science, fuck yeah, i love science

[@thesciencefurry]

Hmm don't think so, maybe I need a hat like him xD

[@crimester]

@@thesciencefurry yess

[@FangTheManokit]

Beryllium and asbestos?!?!?..... please tell me you did this with way more protection than needed 😭💀🙏🏻

[@thesciencefurry]

@@FangTheManokit what? Where did I say that xD

[@FangTheManokit]

@@thesciencefurry 2:06

[@FangTheManokit]

@@thesciencefurry My apology if i heard anything wrong btw.

[@thesciencefurry]

@@FangTheManokit I think I need to add subtitles 💀 I said Barium which sounds similar but I said "The best is the three of them" Not asbestos😂

[@atom1kcreeper605]

.... Spaghetti

[@siddharth-wy2kp]

what's good?

[@thesciencefurry]

Hey :3

[@thunderwolf8908]

Fellow furry

[@SlavTiger]

magnentron

[@delphicdescant]

typos are the best way to boost engagement, after all.

[@thesciencefurry]

Why tf did I gave you a heart and then just didn't correct it until now🤣

[@MirlitronOne]

You can't even spell "magnentron"...

[@cianmoriarty7345]

3:56 um, why didn't you just put a kink in the wires to shorten them? 🤔

[@thesciencefurry]

@@cianmoriarty7345 it would touch the glass if I did this. Which isn't good