[TCML] Re: Question about loss in Violet Ray configuration

[glimmerest_star@xxxxxxxxxxxxx]

Dave,

I suspect you're correct that is what is happening and Im going to try a much shorter HV output cable before giving up on the configuration.  Thank you for the input!

I do ensure a gap as you describe; depends on the device whether I use an air gap or a sliver of mica or other protective gap. And whenever I can I install a ground wire and 3 prong plug.  Mostly museum or collectible restorations, but you never know when someone might decide to fool around.

Thank you!
Glimmer
 

Glimmerest,

I suspect that you are losing current capacitively to ground through 
your long HV cable.  If you think about it, the glass discharge tubes 
are really just more atmosphere contained in a bottle, albeit at a lower 
pressure, and perhaps with a selected gas in them.

Your long wire represents a distributed capacitive leak to ground.  If 
you had a 6 foot long glass tube connected directly to the HV coil, it 
probably wouldn't be very bright at the end farthest from the coil, either.

A word of caution:  If you have repaired blue ray machines, you should 
have noted that there has to be some sort of protective gap in the Hv 
discharge path.  If you have ever pulled apart one of the metal leak 
tester tips with the red Bakelite sleeves, you will have noticed that 
there is a perhaps 1/16" spark gap within this assembly.  I believe that 
the purpose of this gap is to prevent direct DC continuity in case you 
happen to plug the two wire cord in the wrong way, and end up with the 
bottom of the HV coil connected to the hot 120 VAC line.  If you are 
direct wiring to the HV outputs, you should put some sort of gap in the 
path for the same reason.

If you are using glass tubes, they provide the protection, but if you 
have a metallic connection to the HV coil, you should have some sort of 
protective gap.

Probably the only solution to your original question is to reassemble 
the devices in the same configuration that they were originally built.

HTH,
Dave

On 10/16/2010 4:18 PM, glimmerest_star@xxxxxxxxxxxxx wrote:
> Hello!  Been quite a few years since I've posted, but I do keep up reading the list!
>
> I've been rewiring, grounding and restoring antique violet ray devices for a number of years.  These were quite popular as 'medical' equipment 90 years ago.  They are generally two parts with the magnet coil, interrupter and capacitor residing in a separate electrical box, extending to a handle containing the other coil, and ending in a jack for the noble gas discharge tubes in different shapes.  The tubes light up beautifully and deliver a nice sized spark, sometimes up to 1 inch.
>
> I've tried getting creative with some and putting all the components in the box, with a 4'-6' cable running out that serves just to attach to the jack which holds the glass tubes. For some machines that are missing their original handles it's been kind of necessary as well.  Here's the dilemma:
>
> The cable seems to carry the voltage without any loss; the length of streamer from the far end of the cable is as long as it is coming directly from the coil.  If I use a metal electrode in place of a glass one, there is also no perceived loss.  BUT when I use a glass discharge tube at the far end of the cable, the loss is evident, spark is bafflingly small and some tubes will barely light up.
>
> Does anyone have an idea of what is happening here?  I'm getting SOME kind of loss; and how could I try to counter it?


_______________________________________________
Tesla mailing list
Tesla@xxxxxxxxxx
http://www.pupman.com/mailman/listinfo/tesla