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*UPDATE* Ruhmkorff Coil & Crookes Railway Cathode Tube

P

ped

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Ok, was going to bung this in the TC thread but didn't want to derail it.

After seeing this on PhotonicInduction's channel, I had to get :D .

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The tube

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again..

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and again

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andddd again

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and lastly..

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The Ruhmkorff coil.

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Gap of 6"

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anddd..

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...

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Stills of the Crookes tube, this was really hard to photograph.

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...

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...

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The arcs of the Ruhmkorff Coil are ridiculous (and LOUD!) , I'll let the videos do the talking.







My new favourite toy, 'till I find something else :) .

Ped
 





Re: Ruhmkorff Coil & Crookes Railway Cathode Tube

Very Very Nice ,

if you don't mind me asking , did you purchases this within the Uk ?
 
Re: Ruhmkorff Coil & Crookes Railway Cathode Tube

Very nice! Crookes and Geissler tubes are loads of fun! Just beware there is some soft Xray output whenever glass fluoresces green, so limit exposure times and mind the inverse square rule. Because they're soft xrays, standard metal-walled-GM-tube Geiger counters won't register anything, but your flesh will.

There's a vertical variant of the railway tube which looks like a standard radiometer that I think outperforms the standard railway as it will spin indefinitely when powered, as opposed to the traditional one which needs polarity reversal once the track length is used up.
 
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Re: Ruhmkorff Coil & Crookes Railway Cathode Tube

SHUT UP and take my money
 
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Re: Ruhmkorff Coil & Crookes Railway Cathode Tube

I thought the green particles on the glass were phosphor particles that have come off the blades of the coated wheel? I was aware of the Xray emissions ...now you have me worried :undecided: , am I going to turn green, rip off my T shirt and run around throwing cars at helicopters? :poke:
 
Re: Ruhmkorff Coil & Crookes Railway Cathode Tube

I'd bet the phosphor particles are a deliberate aesthetic addition to the glass. They would be excited with UV. Xrays are not a concern at the currents (likely <1mA) you are operating.
 
Re: Ruhmkorff Coil & Crookes Railway Cathode Tube

very sweet!!!
 
Re: Ruhmkorff Coil & Crookes Railway Cathode Tube

Ok well the coil "driver" didn't last long :crackup:

Anyone got any SIMPLE circuits to drive this off 240V?

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Re: Ruhmkorff Coil & Crookes Railway Cathode Tube

I couldn't find that ruhmkorff in the link. Pretty cool stuff there.
 
Re: Ruhmkorff Coil & Crookes Railway Cathode Tube

The classical coil relies on self-oscillation of an integrated relay and uses no silicon. There's clearly silicon in your weird "modern" version. Can you post a schematic of what's there, or perhaps a few pictures detailing the connections, boards, and parts?
 
Re: Ruhmkorff Coil & Crookes Railway Cathode Tube

^^ Year sure, will do in a bit.

EDIT.

Large pics, mobile users beware.

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Re: Ruhmkorff Coil & Crookes Railway Cathode Tube

A resistor code of "black black black black" is the wrong value, clearly. I'm just not sure what it should be. It's a little complex to try to reverse engineering by having someone else take pictures. I can't tell that rotary switch topology without a close-up, I can't tell how that pot is wired or why it has 5 terminals (yet another switch I suppose), or the underside of that PCB or that IC's part number. It would be easy if I had it in person.

It's clear, however, they're using a triac or SCR to dump that cap into the coil every mains half cycle. The best I can suggest is replacing that popped resistor with 100k and lowering the value until something happens. Perhaps email the supplier and ask them what the value is.

If you're feeling adventurous, you could replace most of the circuitry with an off-the-shelf triac dimmer, and just drive the cap/coil with that.
 
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Re: Ruhmkorff Coil & Crookes Railway Cathode Tube

Yeah you're right about the SCR, and the resistor color code, incedentally it's a 5 band resistor, the fifth bad is "black" :crackup: , but if you think a 100k (to start off) by all means I'll try that. The pot is a 220k, with a mains switch built in...but the mains switch failed, hence my "aftermarket" mod.
 
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Re: Ruhmkorff Coil & Crookes Railway Cathode Tube

Very cool, I had not seen that before.
 
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