What to do with tubes?

[null47]

Hello, first apologies if this is not the proper place to post this kind of thread, I am new here, had a look around and still had not find a more fitting place. If any of the mods find a more fitting place for this thread, please notify me and feel free to move it.

With that out of the way, Hello again, so... on tubes, it is no secret to the members of this forum that tubes are well sought after for amps and preamps, but I'd like to do something different and also, I'd like some sugestions on low voltage tube amp designs. I managed to get my hands on 4 Sylvania 6jt8(these are tv tubes pentode-triode on the same tube) and about 20 voskhod 6ж1п(some dub it as 6j1p, from what little I gathered this is some vhf, frequency stuff tube), and I'd like to know what can I do with it besides amps, I know that nowdays all is done with the little three legged black things(transistors ) but I want to go "old school" for the sake of fun. I had a look around google and youtube but all I can find is tube amps and pre amp and audio related stuff, so I ask... what else can I do? Any suggestions? links, resources? Ideas or concepts? Anything like this would be much appreciated.

Also on my searches I came across this
http://www.audiodesignguide.com/New2A3/ETF06TS.pdf
While reading there is a section that says current trickler, what is a current trickler? And what would it be used for? I looked almost everywhere and no data was available

As for the second part of my quest, the low voltage stuff with tubes, I know it is madness, but I am still interested, and I fould some things like the 3.3v tube amp on hack a day, and some that used a 555 dc voltage booster to get around 100-200v from a much lower voltage, i.e. 5v or 12v I made some of these myself with slight mods to suit my needs on other projects... though, I wonder is it possible to drive tubes on low voltages? And is it possible without solid state components or do I have to go hybrid on this one.

In advance thanks.

-Null47
-edit1: minor text corrections

 

[rock soderstrom]

and about 20 voskhod 6ж1п(some dub it as 6j1p,

I think, this is the soviet version of the 6AK5 aka EF95. Close relative to 5654. Pretty good tube for tube microphones!

Nice project for a this tube:

https://groupdiy.com/threads/st12-6...-tube-microphone-in-the-world-full-pro.62601/

 

[Wavelength]

I use to fix Corvette 57 radios in College and it was tube based. I ran over to Lima (not the end of the world but you can see it from there) and Fair Radio and while I was there (granted this is 1980-81) I picked up a bunch of ECC86/6GM8 which are low voltage tubes. You have to watch out for grid current as it makes it with lower plate voltages. I also bought a ton of 6418 which are directly heated so a little more work in understanding how to use them is required. I feed those with a LM317L and a 121 ohm resistor to make a 10ma filament supply and run them in triode (i.e. screen to plate) at 0.33ma which of course is high output Z so I use an JFET 2SK189 in source follower.

 

[gyraf]

..the referred "current trickler" is describing the tubes' mode of function when you just add all grids together and use as grid. This gives very high mu, but also results in very-high internal resistance in the tube, i.e. you can't really draw any current from it (for e.g. controlling next stage), so there's not much irl use for this setup..

 

[merlin]

all I can find is tube amps and pre amp and audio related stuff, so I ask... what else can I do?

Test equipment like a high-voltage sine oscillator? Adjustable power supply? Home made oscilloscope? Radio receiver? There's a lot of stuff like this on hackaday.
https://hackaday.com/2023/03/29/two-tube-spy-transmitter-fits-in-the-palm-of-your-hand/
http://www.netzener.net/index.php/project-articles/10-one-tube-am-radio

I wonder is it possible to drive tubes on low voltages? And is it possible without solid state components or do I have to go hybrid on this one.

It is possible, depending on what you want to acheive.
https://valvewizard.co.uk/Triodes_at_low_voltages_Blencowe.pdf