Building a DIY Triode Vacuum Tube

[@jdflyback]

oh my god this is great.

[@thesciencefurry]

If it would actually amplify :p But i'm getting there....eventually.

[@jdflyback]

I bet it is but it might just have a high plate resistance. For a voltage amplifier a 470k plate resistor would be a good starting point. For driving a speaker I have had good luck with the hammond 1760C output transformer. It seems to work best with the primary configured as 8kOhms and with the 3.2 Ohms secondary connection being used to drive an 8 ohm speaker. I am really jealous of your seals by the way. I still have days where my seals end up having bubbles on the surface of the tungsten and it makes me sad :3

[@thesciencefurry]

@@jdflyback That's why I make the seals individually and then seal them in. So I can select which ones are good and which ones are not. I was watching your and Dalibors videos and was scratching my head how this supposed to work. But everyone has their own methods.

[@SignalDitch]

I don't know how I missed this upload originally but this is fantastic work! I noticed on the tubes you showed at the beginning that they appeared to be evacuated from the top instead of having a smaller evacuation stem. This is my preferred method so far as it avoids extra glasswork, although it doesn't allow for a nice, round top. Hopefully I'll also be publishing a triode video soon! Cheers!

[@mfbfreak]

It might help you to characterise the tube. Based on that you can improve the amplifier circuit. Measure the amplification (mA/v grid voltage) at different anode voltages.

[@SciDOCMBC]

Did you build the spot welder yourself? It would be interesting to see it in more detail in a video. Great video btw.

[@thesciencefurry]

There are tons of videos covering that and it's super simple. So I wouldn't make a video on that

[@zyeborm]

Pretty darn great for a first attempt mate!

[@thesciencefurry]

Technically the third :p

[@zyeborm]

@@thesciencefurry first one you got working on KZbin I'm calling it the first ;-) Probably only down to tweaking your spacing, voltage and vacuum to get a good amplifying tube at this rate man. Inspiring.

[@smudge3446]

Awesome build! I've always wondered: why is solder never used? Every homemade tube I see seems to use this spot welding approach instead for all the connections.

[@smudge3446]

Ah maybe it is the temperature even though high temp solder exists, not sure how hot these things get but I assume its pretty hot :)

[@thesciencefurry]

@@smudge3446 yeah it would melt. You probably could get away with it on the plate for example but I wouldn't risk it. It gets super hot in there and if some connection fails you can't fix it.

[@FriesOfTheDead]

Wow! I build tube amps for guitar. This is next level :3

[@piotrchojnacki5679]

I've once seen a scan of an old paper(around 60's) from an electronic company where i read that they used a mixture of barium and strontium carbonates with nitrocelulose dissolved in organic solvents to coat their cathodes. I can't remember if they wrote which solvents they used, but I think that acetone would certainly do the job. Maybe it'd stick to the filament better and make an even coating.

[@janno288]

finally some good content on this platform!

[@thesciencefurry]

Aww thx😄 Hopefully I can do some more shenanigans with vacuum tubes.

[@janno288]

@@thesciencefurry Reject Transistors, Embrace TUUUB

[@hobbyrob313]

I hope you will experiment with FM transmitters again! and then test how far you get, but with a good antenna / dipole!? or beter GP? Greetings from the Netherlands! Rob

[@QedleX]

I just love this type of content

[@thesciencefurry]

I would love to see more stuff like this on youtube.

[@niocalsgreogiro]

Really cool project 👏

[@Enderbro3300]

Why couldn't you use something like a mason jar for this? Isolate them from the lid and then pump down the tube? I've wanted to make a neon lamp like that as a proof of concept but I don't have a vacuum pump.

[@thesciencefurry]

Won't hold vacuum well enough and you have to leave it on the pump. At this point you would be better off to build a proper chamber for it. But a normal vacuum pump usually won't cut it.

[@murat_321]

For those who want to make hydrochloric acid here H2so4+nacl=naso4+hcl HCl+H2O= H+ CL-(ions) and O-+H+ and hydrochloric acid.

[@Earthcomputer-d9t]

Can i use copper instead of stainless steel

[@thesciencefurry]

You can't really spotweld copper

[@KeritechElectronics]

Nice work! Anyone who makes their own tubes lands in the "proper respect" area - Glasslinger, jdflyback, Dalibor Farny, Aleksander Zawada, Nick Poole, Gerrit Deruyter, snd now you too :)

[@morrisputman8592]

what kind of vacuum pump did you use?

[@thesciencefurry]

@@morrisputman8592 A two stage pump from mucola

[@morrisputman8592]

@@thesciencefurry thank you for the fast response, my follow up question is: where can i obtain such pump?

[@Medinos]

Nice sehr interessant was du machst ;)

[@hr.differentmind2048]

Nice 👍

[@AllLoudNation365]

Hey!

[@bennettmewes]

yo