Recent Posts

Pages: [1] 2 3 ... 10
1
Solid State Tesla Coils (SSTC) / Re: Plasma Toroid
« Last post by klugesmith on Today at 09:35:18 AM »
Thanks for dimple observations.  And thanks to Dave for showing us that website, with a wealth of details about a lamp technology that filled an important niche for more than a half-century.  Check out the page about sodium migration.   It confirmed that sodium partial pressure can differ substantially from place to place along the tube.  I guess the conditions make diffusion very very slow (for a gas).  Site includes this picture of a demonstration lamp whose heat-retaining coating was removed from right half of arc tube. Outer envelope is warm in left half and hot in right half.


I respect the site's choice to report pressure values in pascals. 0.4 Pa is very close to 3 microns.
In olden days, the exact conversion factor would depend on density of Hg at some temperature, and acceleration of gravity at some place. Now it's easier to remember:
Torr is defined to be 1/760 standard atmosphere. Standard atmosphere is defined to be 101325 pascals.
Hmm, I bet the 101325 was adopted to reasonably match 760 mm of mercury in centuries of barometric instrumentation.

Back to nominal subject of this thread: I guess Alan has his work cut out for him. Get back to xenon wrangling and demonstrate a sodium-doped plasma toroid. :)
2
Solid State Tesla Coils (SSTC) / Re: Plasma Toroid
« Last post by DashApple on Today at 07:37:22 AM »

Dave, do your lamps (SOX series ?) have little dimples at intervals along arc tube, as intentional cold spots for sodium to go when lamps are off?


I have a few newer lamps in the 55W to 180W range with the dimples, I think one reason for them is they are there to provide more even distribution of sodium during the warmup phase on the longer tubes and perhaps a longer life,  after enough time the sodium in the dimples will go and never come back .

Some of my older 135W lamps lack the dimples and the sodium sits in the U at the lamp top
3
Besides UD2.9, there are at least two other pulse-skip offshoots of UD2.7 that use simple logic chips:
https://highvoltageforum.net/index.php?topic=2054.msg15611#msg15611
https://highvoltageforum.net/index.php?topic=2265.msg16555#msg16555
Not certain if that is exactly what you are looking for.
4
Solid State Tesla Coils (SSTC) / Re: Plasma Toroid
« Last post by davekni on Today at 04:51:33 AM »
Looks like Kludgesmith is correct about relative pressures.  On the order of 1000Pa for noble fill gasses and 0.4Pa for sodium vapor.  Found another reference:
http://www.lamptech.co.uk/Documents/SO%20Vapour.htm
http://www.lamptech.co.uk/Documents/SO%20Gas.htm

Quote
I believe, that the gases you used are too thermally conductive, requiring more power than available to sustain a hot torus.
Good point.  I hadn't thought about thermal conductivity.  Some day, after many other projects on my list are past, I hope to try argon with higher field strength.
5
I agree electroboom's explanation is a bit odd at points 4 and 5.  Its much better to think in terms of current, since a BJT is controlled by its base current, not its base voltage.
So at the BJT base we have a DC bias current from the resistor + the AC current flowing in the LC tank formed by the secondary winding and its stray C.
That AC current gets amplified by the BJT, and drives the primary coil, driving more energy into the secondary resonant tank. On each cycle more energy is added to the tank, making the AC current bigger, and the AC voltage at the output terminal bigger too.  Eventually the AC current is large enough that the BJT turns off completely for half of each cycle - so its running in Class C.  You can see why the phasing is critical - get it backwards and the amplified signal will oppose the oscillation, instead of enhancing it.
 The reverse diode provides a path for the AC half cycle that would otherwise be blocked by the base-emitter junction being reverse biased. Without the diode the current has to find another path, and might blow the BJT in the process.
6
Sell / Buy / Trade / [WTB] IF D95T / IF D95OC optic receiver
« Last post by RoamingD on November 29, 2022, 10:23:35 PM »
Hello, as I am unable to find anywhere the fiber optic receivers, I need your help to sell and mail me this part. I need to mention that I live in Europe - Romania so if you can mail it as a letter it would be great.
7
Did you check out the prof9dc PCB pack? It has UD2.7 and UD2.9 (pulse skipping)

https://highvoltageforum.net/index.php?topic=353.0
8
If anyone could point to where schematics for versions of UD2.x post-2014, I'd be interested to  dig in.  I don't mean the change of tactics with UD3 --aware of Netzpfuscher's and other's work -- but somewhere in its evolution before coding became involved.

I know Lone Oceans (Gao Guangyan) catalogued 2.7C very comprehensively in 2014; that seems to be the last open-source work on late 2.7+
 pre-UD3.x versions. He noted  the contributions of Eric Goodchild & Bart Anderson through the evolution from Steve Ward's foundation design, as well as his own.

Someone I was in comms with sent me photos of a post-2014 board a few years ago.  I never found out the provenance of it & we have lost touch.  Among other differences from 2.7C, I did find a note from visual inspection --

*Shorting jack for phase lead adjustment eliminated
*C33 in D2.7 (part of hysteresis loop for TL3116) becomes C25 in this later version
*Chassis-mounted LED's become part of board population
*PCB was built for the two channels (logic and gate drivers) but board wasn't redesigned, simply entire CH2 left unpopulated
*Overcurrent pots. mounted vertically on PCB

I can't see there was any substantive possible improvement from 2.7C, so I'm curious what was actually done that isn't cosmetic in 2.7+ versions  Were there any known glitches remaining after 2.7C?



9
Slow motion Tesla Coil recordings of SSTC sparks. Recorded at 8000 frames per second and replayed at 15-30 frames per second. Notice the step leader, known from natural lightning strikes and the hot spots that might be forming from collapsing plasma channels.

/>
What do You think about the hot spot from collapsing plasma channel idea/theory?
10
Solid State Tesla Coils (SSTC) / Re: Plasma Toroid
« Last post by alan sailer on November 29, 2022, 04:08:00 PM »
kurtrox,

I'm sorry that you are having such problems. I used the exact same diagram that you linked to and it worked on turn-on.

I happen to own an LCR meter so measuring the coils was easy and accurate. Plastic is an ideal coil form and should have no effect on the inductor unless you are using some weird plastic. PVC tubing works great.

If the MOSFET is heating too much then the circuit is probably not operating class E and needs to be tuned.

I bundled the output coil because I wanted to keep it somewhat neat. Keeping the coil bundled does affect the inductance somewhat.

Is your coil running at 10MHz? How are you establishing the inductance? You can measure an unknown inductance be resonating it with a known capacitance...
Pages: [1] 2 3 ... 10

* Recent Topics and Posts

post Re: Plasma Toroid
[Solid State Tesla Coils (SSTC)]
klugesmith
Today at 09:35:18 AM
post Re: Plasma Toroid
[Solid State Tesla Coils (SSTC)]
DashApple
Today at 07:37:22 AM
post Re: UD2.7 onwards - post-2014 changes published anywhere?
[Dual Resonant Solid State Tesla coils (DRSSTC)]
davekni
Today at 05:17:26 AM
post Re: Plasma Toroid
[Solid State Tesla Coils (SSTC)]
davekni
Today at 04:51:33 AM
post Re: Slayer exciter circuit - struggling with how it works
[Solid State Tesla Coils (SSTC)]
Twospoons
Today at 04:43:37 AM
post [WTB] IF D95T / IF D95OC optic receiver
[Sell / Buy / Trade]
RoamingD
November 29, 2022, 10:23:35 PM
post Re: UD2.7 onwards - post-2014 changes published anywhere?
[Dual Resonant Solid State Tesla coils (DRSSTC)]
Mads Barnkob
November 29, 2022, 09:14:10 PM
post UD2.7 onwards - post-2014 changes published anywhere?
[Dual Resonant Solid State Tesla coils (DRSSTC)]
AkashaStar
November 29, 2022, 07:32:37 PM
post 8000FPS Slow Motion Tesla Coil Spark Formation and Collapsing Hot Spots
[Solid State Tesla Coils (SSTC)]
Mads Barnkob
November 29, 2022, 05:21:49 PM
post Re: Plasma Toroid
[Solid State Tesla Coils (SSTC)]
alan sailer
November 29, 2022, 04:08:00 PM
post Re: Plasma Toroid
[Solid State Tesla Coils (SSTC)]
kurtrox
November 29, 2022, 05:51:59 AM
post Re: Induction cooker without electronics
[Electronic Circuits]
Solhi
November 29, 2022, 01:25:43 AM
post Re: Induction cooker without electronics
[Electronic Circuits]
Twospoons
November 28, 2022, 10:09:56 PM
post Re: Plasma Toroid
[Solid State Tesla Coils (SSTC)]
Uspring
November 28, 2022, 06:01:14 PM
post Slayer exciter circuit - struggling with how it works
[Solid State Tesla Coils (SSTC)]
Tatranka
November 28, 2022, 02:57:17 PM
post Re: Induction cooker without electronics
[Electronic Circuits]
Solhi
November 28, 2022, 11:38:26 AM
post Re: Induction cooker without electronics
[Electronic Circuits]
klugesmith
November 28, 2022, 11:22:51 AM
post Re: Induction cooker without electronics
[Electronic Circuits]
Solhi
November 28, 2022, 05:55:16 AM
post Re: Plasma Toroid
[Solid State Tesla Coils (SSTC)]
klugesmith
November 28, 2022, 05:21:37 AM
post Re: Plasma Toroid
[Solid State Tesla Coils (SSTC)]
davekni
November 28, 2022, 03:26:55 AM
post Re: Plasma Toroid
[Solid State Tesla Coils (SSTC)]
klugesmith
November 28, 2022, 02:09:06 AM
post Re: Plasma Toroid
[Solid State Tesla Coils (SSTC)]
alan sailer
November 28, 2022, 12:06:02 AM
post Re: Induction cooker without electronics
[Electronic Circuits]
klugesmith
November 27, 2022, 06:05:52 PM
post Re: Induction cooker without electronics
[Electronic Circuits]
Solhi
November 27, 2022, 01:24:05 PM
post Re: ZVS driver won't oscillate
[Electronic Circuits]
davekni
November 27, 2022, 06:21:04 AM
post Re: Induction cooker without electronics
[Electronic Circuits]
klugesmith
November 27, 2022, 01:13:28 AM
post Re: Oh Lawd, I got dem Op-Amp blues!
[General Chat]
AkashaStar
November 26, 2022, 06:49:16 PM
post Re: ZVS driver won't oscillate
[Electronic Circuits]
AstRii
November 26, 2022, 04:48:39 PM
post Re: IF D95T vs IF D95OC
[Dual Resonant Solid State Tesla coils (DRSSTC)]
RoamingD
November 26, 2022, 06:56:51 AM
post Re: IF D95T vs IF D95OC
[Dual Resonant Solid State Tesla coils (DRSSTC)]
alexhanyuan
November 25, 2022, 11:28:15 PM
post Re: Induction cooker without electronics
[Electronic Circuits]
Solhi
November 25, 2022, 12:05:50 PM
post Re: Induction cooker without electronics
[Electronic Circuits]
Solhi
November 25, 2022, 07:53:52 AM
post Re: Induction cooker without electronics
[Electronic Circuits]
Solhi
November 24, 2022, 08:08:48 AM
post Re: EEFL backlight circuits
[Light, Lasers and Optics]
klugesmith
November 24, 2022, 07:26:49 AM
post Re: Air cored inductors proximity to conductive objects
[General Chat]
davekni
November 24, 2022, 03:02:11 AM
post Re: Solid State “rheostat” that will withstand high electrostatic fields
[General Chat]
AkashaStar
November 24, 2022, 02:25:42 AM
post Re: Induction cooker without electronics
[Electronic Circuits]
Solhi
November 24, 2022, 01:45:33 AM
post Re: Air cored inductors proximity to conductive objects
[General Chat]
John123
November 23, 2022, 11:27:18 PM
post Stepper motor drive without switching
[Electronic Circuits]
klugesmith
November 23, 2022, 10:23:07 PM
post Re: Air cored inductors proximity to conductive objects
[General Chat]
Twospoons
November 23, 2022, 09:29:01 AM
post Re: Vacuum pump
[Laboratories, Equipment and Tools]
Alberto
November 23, 2022, 08:45:37 AM
post Re: Air cored inductors proximity to conductive objects
[General Chat]
davekni
November 23, 2022, 04:44:20 AM
post Air cored inductors proximity to conductive objects
[General Chat]
John123
November 23, 2022, 01:10:17 AM
post Re: Post-Soviet Tesla Coil Teardown and Test
[Solid State Tesla Coils (SSTC)]
Mads Barnkob
November 22, 2022, 08:40:19 PM
post Re: Ericsson RBS 6601 RRUS 12 analysis(kind of)
[Electronic Circuits]
Da_Stier
November 22, 2022, 08:22:09 PM
post Re: Ericsson RBS 6601 RRUS 12 analysis(kind of)
[Electronic Circuits]
Kirby4life
November 22, 2022, 08:45:06 AM
post Ericsson RBS 6601 RRUS 12 analysis(kind of)
[Electronic Circuits]
RickNitro
November 22, 2022, 08:36:11 AM
post Re: Vacuum pump
[Laboratories, Equipment and Tools]
davekni
November 22, 2022, 06:42:31 AM
post Re: Vacuum pump
[Laboratories, Equipment and Tools]
Twospoons
November 22, 2022, 06:40:32 AM
post Re: Vacuum pump
[Laboratories, Equipment and Tools]
klugesmith
November 22, 2022, 04:53:40 AM
post Re: Vacuum pump
[Laboratories, Equipment and Tools]
Twospoons
November 22, 2022, 02:17:08 AM
post Re: Vacuum pump
[Laboratories, Equipment and Tools]
klugesmith
November 21, 2022, 11:03:04 PM
post Re: Vacuum pump
[Laboratories, Equipment and Tools]
Alberto
November 21, 2022, 09:55:02 PM
post Re: Induction cooker without electronics
[Electronic Circuits]
Solhi
November 21, 2022, 03:09:26 PM
post Re: Post-Soviet Tesla Coil Teardown and Test
[Solid State Tesla Coils (SSTC)]
LoOdaK
November 21, 2022, 09:38:22 AM
post Re: Trichel pulses
[Electronic Circuits]
klugesmith
November 20, 2022, 10:05:15 PM
post Trichel pulses
[Electronic Circuits]
haversin
November 20, 2022, 09:48:37 PM
post Re: Induction cooker without electronics
[Electronic Circuits]
klugesmith
November 20, 2022, 07:17:36 PM
post Re: Some questions about my first drsstc.
[Dual Resonant Solid State Tesla coils (DRSSTC)]
mthome4
November 20, 2022, 02:28:22 PM
post Post-Soviet Tesla Coil Teardown and Test
[Solid State Tesla Coils (SSTC)]
Mads Barnkob
November 20, 2022, 02:03:49 PM
post Re: Induction cooker without electronics
[Electronic Circuits]
Solhi
November 20, 2022, 10:00:13 AM
post Re: TV flyback number of primary turns rule of thumb
[Transformer (Ferrite Core)]
davekni
November 20, 2022, 05:13:12 AM
post Re: Plasma Toroid
[Solid State Tesla Coils (SSTC)]
davekni
November 20, 2022, 05:08:31 AM
post Re: Plasma Toroid
[Solid State Tesla Coils (SSTC)]
alan sailer
November 20, 2022, 01:27:00 AM
post Re: Basic Gate driving doubts
[Solid State Tesla Coils (SSTC)]
davekni
November 19, 2022, 10:12:14 PM
post Re: TV flyback number of primary turns rule of thumb
[Transformer (Ferrite Core)]
John123
November 19, 2022, 09:57:35 PM
post Re: Basic Gate driving doubts
[Solid State Tesla Coils (SSTC)]
prabhatkumar
November 19, 2022, 09:50:23 PM
post Re: Basic Gate driving doubts
[Solid State Tesla Coils (SSTC)]
davekni
November 19, 2022, 08:26:45 PM
post Re: Vacuum pump
[Laboratories, Equipment and Tools]
davekni
November 19, 2022, 06:53:17 PM
post Re: Vacuum pump
[Laboratories, Equipment and Tools]
klugesmith
November 19, 2022, 06:05:47 PM
post Re: Vacuum pump
[Laboratories, Equipment and Tools]
Alberto
November 19, 2022, 05:34:46 PM
post Re: Induction cooker without electronics
[Electronic Circuits]
Solhi
November 19, 2022, 02:30:04 PM
post Re: Welcome new members, come say hello and tell a little about yourself :)
[General Chat]
AkashaStar
November 19, 2022, 01:56:10 PM
post Re: Buck converter question
[Dual Resonant Solid State Tesla coils (DRSSTC)]
dru
November 19, 2022, 08:03:56 AM
post Re: Induction cooker without electronics
[Electronic Circuits]
Solhi
November 19, 2022, 06:38:00 AM
post Basic Gate driving doubts
[Solid State Tesla Coils (SSTC)]
prabhatkumar
November 19, 2022, 05:37:09 AM
post Re: ZVS driver won't oscillate
[Electronic Circuits]
davekni
November 19, 2022, 03:59:56 AM
post Re: Non-laser pointer
[Light, Lasers and Optics]
klugesmith
November 19, 2022, 03:56:32 AM
post Re: Buck converter question
[Dual Resonant Solid State Tesla coils (DRSSTC)]
davekni
November 19, 2022, 03:36:20 AM
post Re: Vacuum pump
[Laboratories, Equipment and Tools]
davekni
November 19, 2022, 03:26:48 AM
post Re: Vacuum pump
[Laboratories, Equipment and Tools]
Alberto
November 19, 2022, 12:40:33 AM
post Re: ZVS driver won't oscillate
[Electronic Circuits]
AstRii
November 18, 2022, 09:32:33 PM
post Re: Induction cooker without electronics
[Electronic Circuits]
klugesmith
November 18, 2022, 05:48:00 PM
post Re: Audio Modulated CRT Flyback Transformer Loud Sparks
[Transformer (Ferrite Core)]
John123
November 18, 2022, 03:49:12 PM
post Re: TV flyback number of primary turns rule of thumb
[Transformer (Ferrite Core)]
John123
November 18, 2022, 02:56:49 PM
post IF D95T vs IF D95OC
[Dual Resonant Solid State Tesla coils (DRSSTC)]
RoamingD
November 18, 2022, 01:44:38 PM
post Re: Induction cooker without electronics
[Electronic Circuits]
Solhi
November 18, 2022, 11:38:44 AM
post Non-laser pointer
[Light, Lasers and Optics]
klugesmith
November 18, 2022, 10:05:29 AM
post Re: Induction cooker without electronics
[Electronic Circuits]
klugesmith
November 18, 2022, 06:54:55 AM
post Re: Induction cooker without electronics
[Electronic Circuits]
Twospoons
November 18, 2022, 06:29:23 AM
post Buck converter question
[Dual Resonant Solid State Tesla coils (DRSSTC)]
dru
November 18, 2022, 06:10:52 AM
post Re: TV flyback number of primary turns rule of thumb
[Transformer (Ferrite Core)]
davekni
November 18, 2022, 05:53:15 AM
post Re: Induction cooker without electronics
[Electronic Circuits]
Solhi
November 18, 2022, 05:21:52 AM
post Re: Vacuum pump
[Laboratories, Equipment and Tools]
davekni
November 18, 2022, 04:00:04 AM
post Re: Vacuum pump
[Laboratories, Equipment and Tools]
alan sailer
November 17, 2022, 10:24:35 PM
post Re: TV flyback number of primary turns rule of thumb
[Transformer (Ferrite Core)]
John123
November 17, 2022, 08:30:00 PM
post Re: TV flyback number of primary turns rule of thumb
[Transformer (Ferrite Core)]
klugesmith
November 17, 2022, 07:28:16 PM
post Re: TV flyback number of primary turns rule of thumb
[Transformer (Ferrite Core)]
John123
November 17, 2022, 03:38:00 PM
post Re: TV flyback number of primary turns rule of thumb
[Transformer (Ferrite Core)]
davekni
November 17, 2022, 04:03:51 AM
post Re: what type of diode is better for make high voltage diode?
[Voltage Multipliers]
davekni
November 17, 2022, 03:57:40 AM

SimplePortal 2.3.6 © 2008-2014, SimplePortal