Advice on vacuum tube tesla coil?

[RayRay1132]

I have returned lol. Anyways I've been wanting to build myself a vacuum tube tesla coil, more specifically a high frequency vttc kinda like the on that the youtube styropyro built. I came across these two 100TH like vacuum tubes with a maximum power dissipation of about 250 watts at 3000 volts. They came out of some kind of radio trasmitter. Would these work good for a tesla coil. Any advice would be greatly appreciated as I don't have much experience with anything other than standard spark gap coils lol.

Thanks in advance -Ray KD2JID

 

[danadak]

Something like this maybe....

100TH tesla coil circuit at DuckDuckGo

DuckDuckGo. Privacy, Simplified.

duckduckgo.com

Regards, Dana.

 

[Lightium]

I found this and this:

https://store-p8gj3ieclp.mybigcommerce.com/content/datasheets/schematic_833avttc.pdf

https://frank.pocnet.net/sheets/090/1/100TH.pdf

 

[Fluffyboii]

Did you find anything about this. I was curious to make something similar but lack of resources about using these large vacuum tubes puts me off. Also stuff that are needed make that type of circuits are often rare and expensive.

 

[crutschow]

Another example,

 

[Ramussons]

I hope that you are aware of the dangers and you will need to be very careful. The primary voltage is itself is Fatal, and that combined with High Frequency.
All the best!

 

[Fluffyboii]

I hope that you are aware of the dangers and you will need to be very careful. The primary voltage is itself is Fatal, and that combined with High Frequency.
All the best!

I have few more years of work to do before I can dream of using the 2KW pentode tube I have. I don't even know if its seals are still intact or flament is not cracked and I can not really test it without the socket to connect it to a 12.6V 35A flament transformer which I don't have. I want to use it as an high power AM transmitter like this guy did: https://www.hayseed.net/~jpk5lad/4-1000A Amp/Building the 4-1000A.htm
Tesla coil is just another possibility if tube works well. I doubt I will get hold of another one like that.

 

[rjenkinsgb]

I want to use it as an high power AM transmitter like this guy did:

Note that the circuit shown & in the link is only for a power amplifier stage, not a transmitter.
The 4-1000A seems to list for around £800 new!

I've still got a few 4CX250B valves [tubes] among others; somewhat lower rating but a fraction the price!

ps. Transmitting without a licence is likely to get you unwanted attention and legal expenses..

 

[Fluffyboii]

Note that the circuit shown & in the link is only for a power amplifier stage, not a transmitter.
The 4-1000A seems to list for around £800 new!

I've still got a few 4CX250B valves [tubes] among others; somewhat lower rating but a fraction the price!

ps. Transmitting without a licence is likely to get you unwanted attention and legal expenses..

I don't really understand that circuit since it is drawn weirdly but the vacuum tube I got is a tetrode like 4-1000A except it is up to 2KW. I think he is using it like a triode in the schematic since top grid is grounded. The tube I have is TH4T4100 I opened a thread on this forum about it. Can't it be used in a similar fashion? I mean powering something like that up is still quite impossible with the tools I have and my incapability of designing stuff that doesn't self destruct. I am not capable of designing a vacuum tube amplifier while struggling with analog mosfet design. And also autorities probably wouldn't like the interference it would cause as you said. But I really want to transmit my voice over RF signals even if it is for a short time period. Its been my unreasonable dream ever since I got the giant tube. Probably declaring this on this forum wasn't a smart idea since anyone who writes vacuum tube am transmitter on google can find my posts :/

 

[rjenkinsgb]

The circuit is pretty normal for a valve HF PA; many of the components are for impedance matching to the 50 Ohm input and output connections, and others are for decoupling the supplies etc. to prevent unwanted radiation or signal cross-coupling

The valve is a type of "Screen grid" tetrode - the second grid is used to isolate the control (first) grid from the capacitive effects of the anode, which prevents unwanted feedback and improves performance.


Grab a copy of the ARRL handbook - it will give you a lot of information on electronics generally, as well as radio equipment.

Some years are available on archive.org

You can download older ones, eg.

The 1989 ARRL Radio Amateurs Handbook : ARRL : Free Download, Borrow, and Streaming : Internet Archive

Radio amateur handbook for 1989. For the purposeof preservation.

archive.org

The ARRL 1986 Radio Amateur Handbook : ARRL : Free Download, Borrow, and Streaming : Internet Archive

Radio Amateur handbook as published by the ARRLin 1986 for preservation for the human race.

archive.org