what is this high voltage display device called?

Branden

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Nov 17, 2019, 7:27:30 PM11/17/19

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What I'm thinking of is not a plasma globe, although, like the globe, it
too is intended primary for display. If I were to describe it, I
remember it being made out of glass, maybe 1-2 feet in diameter, and
nearly flat in thickness. Electric discharges from the center to the
edge of the glass and looked a lot like lightning. I remember these
devices being used in Star Trek The Next Generation used behind the
heads of Borg drones. They used to be in Spencers too available for
purchase.

Branden

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Nov 17, 2019, 8:08:23 PM11/17/19

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Here's an image:

https://i.imgur.com/72YjfM9.jpg

Branden

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Nov 17, 2019, 9:16:21 PM11/17/19

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On 11/17/19 7:27 PM, Branden wrote:

Ok, I found it. Luminglas or plasma plate or plasma disk. Wow, they
are really costly now. The ones in Spencer's 20 years ago were around
$40 for 15 inch size... now it looks like at least 3 times that!

Cursitor Doom

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Nov 18, 2019, 8:45:13 AM11/18/19

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On Sun, 17 Nov 2019 21:16:17 -0500, Branden wrote:

> Ok, I found it. Luminglas or plasma plate or plasma disk. Wow, they
> are really costly now. The ones in Spencer's 20 years ago were around
> $40 for 15 inch size... now it looks like at least 3 times that!

Inflation innit. A price tripling over 20 years doesn't seem that
unlikely.

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jla...@highlandsniptechnology.com

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Nov 18, 2019, 10:27:45 AM11/18/19

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An ordinary clear-glass incendescent bulb makes some nice sparks
inside if you apply HF-HV to one side of the filament.

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John Larkin Highland Technology, Inc

lunatic fringe electronics

Jeff Layman

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Nov 18, 2019, 12:31:27 PM11/18/19

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On 18/11/19 13:45, Cursitor Doom wrote:
> On Sun, 17 Nov 2019 21:16:17 -0500, Branden wrote:
>
>> Ok, I found it. Luminglas or plasma plate or plasma disk. Wow, they
>> are really costly now. The ones in Spencer's 20 years ago were around
>> $40 for 15 inch size... now it looks like at least 3 times that!
>
> Inflation innit. A price tripling over 20 years doesn't seem that
> unlikely.

Much too high. In the UK, inflation from 1999 to 2019 accounted for a
price rise of about 72%.
<https://www.officialdata.org/uk/inflation/1999?amount=1>
You have to go back to 1985 for inflation to triple the value in 2019.

--

Jeff

Branden

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Nov 18, 2019, 12:39:43 PM11/18/19

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Looks like I should have bought one at the time. There's now way I'll
shell out 4x for it now. Oh well.

Branden

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Nov 18, 2019, 12:41:53 PM11/18/19

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If you're talking a "plasma globe", yes I have one of those. It is
about 14" diameter and cost me $19 at Walmart about 15 years ago.
However, I see that even those in many cases appear to be somewhat
higher in price, but certainly not nearly as high as the luminglas!

John Larkin

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Nov 18, 2019, 2:49:20 PM11/18/19

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On Mon, 18 Nov 2019 12:41:49 -0500, Branden
<brand...@verizondot.net> wrote:

>On 11/18/19 10:27 AM, jla...@highlandsniptechnology.com wrote:
>> On Sun, 17 Nov 2019 19:27:27 -0500, Branden
>> <brand...@verizondot.net> wrote:
>>
>>> What I'm thinking of is not a plasma globe, although, like the globe, it
>>> too is intended primary for display. If I were to describe it, I
>>> remember it being made out of glass, maybe 1-2 feet in diameter, and
>>> nearly flat in thickness. Electric discharges from the center to the
>>> edge of the glass and looked a lot like lightning. I remember these
>>> devices being used in Star Trek The Next Generation used behind the
>>> heads of Borg drones. They used to be in Spencers too available for
>>> purchase.
>>
>> An ordinary clear-glass incendescent bulb makes some nice sparks
>> inside if you apply HF-HV to one side of the filament.
>>
>
>If you're talking a "plasma globe", yes I have one of those.

No, I meant an ordinary light bulb.

--

John Larkin Highland Technology, Inc

picosecond timing precision measurement

jlarkin att highlandtechnology dott com
http://www.highlandtechnology.com

Cursitor Doom

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Nov 18, 2019, 3:17:23 PM11/18/19

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On Mon, 18 Nov 2019 11:49:12 -0800, John Larkin wrote:

> No, I meant an ordinary light bulb.

John means a lightbulb with a tungsten filament in it which burns very
brightly when a current is passed through it. You have to have attained
great age, like John and I, in order to remember such obsolete atrocities.

John Larkin

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Nov 18, 2019, 3:20:56 PM11/18/19

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On Mon, 18 Nov 2019 20:17:16 -0000 (UTC), Cursitor Doom
<cu...@notformail.com> wrote:

>On Mon, 18 Nov 2019 11:49:12 -0800, John Larkin wrote:
>
>> No, I meant an ordinary light bulb.
>
>John means a lightbulb with a tungsten filament in it which burns very
>brightly when a current is passed through it. You have to have attained
>great age, like John and I, in order to remember such obsolete atrocities.

But don't heat the filament, just apply a lot of high voltage, high
frequency stuff to it.

Branden

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Nov 18, 2019, 3:33:30 PM11/18/19

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On 11/18/19 3:20 PM, John Larkin wrote:
> On Mon, 18 Nov 2019 20:17:16 -0000 (UTC), Cursitor Doom
> <cu...@notformail.com> wrote:
>
>> On Mon, 18 Nov 2019 11:49:12 -0800, John Larkin wrote:
>>
>>> No, I meant an ordinary light bulb.
>>
>> John means a lightbulb with a tungsten filament in it which burns very
>> brightly when a current is passed through it. You have to have attained
>> great age, like John and I, in order to remember such obsolete atrocities.
>
> But don't heat the filament, just apply a lot of high voltage, high
> frequency stuff to it.
>

Yes, Ive applied clear incandescents to a HV source too! It can produce
a different display from an actual plasma globe depending on bulb vacuum
or type of gas used. One has to be very careful of the 25 watt
incandescents though if applied to high voltage. Some of those used to
produce x-rays because they were vacuumed but not backfilled! I think
manufacturers have corrected this nowadays, but 20 years ago they were
not backfilled.

Sjouke Burry

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Nov 18, 2019, 4:59:18 PM11/18/19

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On 18.11.19 21:20, John Larkin wrote:
> On Mon, 18 Nov 2019 20:17:16 -0000 (UTC), Cursitor Doom
> <cu...@notformail.com> wrote:
>
>> On Mon, 18 Nov 2019 11:49:12 -0800, John Larkin wrote:
>>
>>> No, I meant an ordinary light bulb.
>>
>> John means a lightbulb with a tungsten filament in it which burns very
>> brightly when a current is passed through it. You have to have attained
>> great age, like John and I, in order to remember such obsolete atrocities.
>
> But don't heat the filament, just apply a lot of high voltage, high
> frequency stuff to it.
>

Like putting one in the microwave.
To protect the microwave, also put a glass of water inside.
The lamp does not need to be in working order.

Paul Hovnanian P.E.

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Nov 18, 2019, 11:27:09 PM11/18/19

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Part of that price is the size. If you must have a 15" disk, it's going to
cost you. 6" are about $25 to $30.

--
Paul Hovnanian mailto:Pa...@Hovnanian.com
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Branden

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Nov 24, 2019, 4:31:02 PM11/24/19

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On 11/17/19 7:27 PM, Branden wrote:

Just wanted to update that I now actually have thee of the Luminglas
displays! Although eBay prices are out of this world, I found all of
these either on Facebook Marketplace or Craigslist and all for less than
$50 each. A lot more reasonably priced! I remember them charging
anywhere from $25-50 back in the late 90's early 00's when they were in
Spencer's and elsewhere. If they are indeed collector items now, I may
have three chances in the future to sell if I ever grow tired of them.