Author Topic: gdt high frequency ring  (Read 3937 times)

Offline davekni

  • High Voltage Expert
  • ******
  • Posts: 1442
  • Karma: +70/-0
  • Physicist, engineer (electronic), and hobbiest
    • View Profile
Re: gdt high frequency ring
« Reply #20 on: April 04, 2021, 07:10:23 PM »
Thank you for scoping pictures that helps.  Even with a battery-operated scope, always connect the probe "ground" lead to a steady low-impedance node such as VBus- or VBus+ (the planes marked with red "+" and "-" in your picture, or FET source lead connected to VBus-), not to a gate.  Capacitance of the scope and probe lead will distort readings and can disrupt proper circuit operation.

Shifting horizontal position to the left is fine.  Vertical coupling looks to still be "AC".  It is hard to see at the image resolution, but it looks like the "~" symbol in front of the ch1 10V label at the lower left of the scope capture, which indicates AC-coupled mode.  Change the scope vertical channels to DC-coupled.

The "ringing" shown there looks like it may be multiple transitions from the driver.  Does it show up when scoping one GDT input (with scope "ground" to the driver circuit ground, not to the other GDT output)?

For gate waveform scoping, it can be useful to short VBus+ to VBus- with no power supply connected (or supply set to 0V).
David Knierim

Offline balazs

  • High Voltage Enthusiast
  • *
  • Posts: 27
  • Karma: +0/-0
    • View Profile
Re: gdt high frequency ring
« Reply #21 on: April 04, 2021, 09:19:27 PM »
I closed VBus + towards VBus. I provided the feedback signal with a signal generator. I took out the 74hc14 because when it was in the circuit, it didn't work. I connected the feedback signal directly to the ic pins. Probe directly to the GDT. The signal was perfect. However, when I put on the Primer and placed the 30v on it, the signal became bad again.

The oscilloscope was already in DC mode, this "~" signal is just an ornament.




Offline davekni

  • High Voltage Expert
  • ******
  • Posts: 1442
  • Karma: +70/-0
  • Physicist, engineer (electronic), and hobbiest
    • View Profile
Re: gdt high frequency ring
« Reply #22 on: April 04, 2021, 09:40:01 PM »
Thank you for the DC clarification.  (I'm puzzled why the "~" shows up.  I've seen that used on scopes to indicate AC before.)

The probe connections are still reversed.  The alligator-clip is the scope "ground" connection.  It should be on VBus-.  The probe tip should be on the GDT output where it connects to the gate series resistor.

If the "ringing" still shows up with VBus powered and the scope correctly connected, then please probe one of the driver outputs (with scope ground on driver board ground).  If you have two probes, it would be ideal to see both simultaneously on ch1 and ch2.

The GDT output with no VBus power looks fine.  My guess is that half-bridge output is coupling to the antenna somehow.
« Last Edit: April 04, 2021, 09:42:08 PM by davekni »
David Knierim

Offline balazs

  • High Voltage Enthusiast
  • *
  • Posts: 27
  • Karma: +0/-0
    • View Profile
Re: gdt high frequency ring
« Reply #23 on: April 05, 2021, 01:08:17 PM »
I changed the probe leg so the ringing was over. Then I put the 74hc14 back on and tested the antenna. The sign was much prettier than it was.
Would this sign no longer ruin mosfets?


Offline davekni

  • High Voltage Expert
  • ******
  • Posts: 1442
  • Karma: +70/-0
  • Physicist, engineer (electronic), and hobbiest
    • View Profile
Re: gdt high frequency ring
« Reply #24 on: April 05, 2021, 09:21:43 PM »
It still looks like there may be multiple transitions on the GDT input (driver output) with the HC14 connected.  I suggest scoping one of the GDT inputs.

The scope's display of DC coupling appears to be the trigger coupling, not the input channel coupling.  I think you are still in AC-coupled input mode.
David Knierim

Offline John123

  • High Voltage Engineer
  • ****
  • Posts: 227
  • Karma: +5/-0
  • All the gear, no idea. UK
    • View Profile
Re: gdt high frequency ring
« Reply #25 on: April 06, 2021, 06:26:08 AM »
Would some kind of extra filtering or hysteresis help in this case around the 74hc14?

Would this sign no longer ruin mosfets?

Hard to tell, I'd remove the big 400v electrolytic bus filtering capacitor for now and current limit/put a power resistor in series with the supply for testing, that would prevent damaging current spikes in the event of a fault. Have you included the zener gate protection yet?

Also how much of that breadboard is being used here? Those wires jumping around could be coupling into your antenna. Have you got any solderable prototyping board? That would be better and cut out much of the parasitic inductance and capacitance associated with breadboard and jumper wires. I've always had problems using breadboards with this sort of circuit.
« Last Edit: April 06, 2021, 06:33:31 AM by John123 »

Offline balazs

  • High Voltage Enthusiast
  • *
  • Posts: 27
  • Karma: +0/-0
    • View Profile
Re: gdt high frequency ring
« Reply #26 on: April 09, 2021, 07:35:16 PM »
I bought zener diodes and resistors and built the protection. The signal became more beautiful again, and the ringing almost disappeared from it. The oscilloscope has been in DC mode so far, as shown in the first image.
I also measured the signal at the output of 74hc14, this is the second picture. The third image shows the output of the GDT.




Offline davekni

  • High Voltage Expert
  • ******
  • Posts: 1442
  • Karma: +70/-0
  • Physicist, engineer (electronic), and hobbiest
    • View Profile
Re: gdt high frequency ring
« Reply #27 on: April 10, 2021, 03:52:34 AM »
Yes, the 74HC14 scope trace clearly proves the vertical channel is DC-coupled.  The "~" symbol is really strange given that.  Thank you for proving me wrong!

Signals are looking good.  Hope everything continues to go well!
David Knierim

Offline John123

  • High Voltage Engineer
  • ****
  • Posts: 227
  • Karma: +5/-0
  • All the gear, no idea. UK
    • View Profile
Re: gdt high frequency ring
« Reply #28 on: April 10, 2021, 11:02:19 AM »
Much better! Are the zeners getting warm?

Offline balazs

  • High Voltage Enthusiast
  • *
  • Posts: 27
  • Karma: +0/-0
    • View Profile
Re: gdt high frequency ring
« Reply #29 on: April 18, 2021, 01:11:28 PM »
Without Toroid, it worked perfectly, worked for a long time, and had no problems. Then I made a box. The sign here wasn’t that nice, there were falls in it, I didn’t take photos, but it wasn’t big enough
to deal with it. When I first tried it without a totoid, it worked perfectly. Then after I put on the toroid and the interrupter and duty frekvenci, it burned down, the 2 mosfet. After I replaced it, the signal became more beautiful again.
 I don’t know if that could have caused the death of these mosses.




Offline balazs

  • High Voltage Enthusiast
  • *
  • Posts: 27
  • Karma: +0/-0
    • View Profile
Re: gdt high frequency ring
« Reply #30 on: April 19, 2021, 05:03:29 PM »
After further attempts, strange falls occurred in the signal. Why can this be?





« Last Edit: April 19, 2021, 05:05:08 PM by balazs »

Offline davekni

  • High Voltage Expert
  • ******
  • Posts: 1442
  • Karma: +70/-0
  • Physicist, engineer (electronic), and hobbiest
    • View Profile
Re: gdt high frequency ring
« Reply #31 on: April 20, 2021, 02:28:12 AM »
Your half-bridge is nicely constructed for low parasitic inductance.  However, I expect you are now experiencing issues with noise coupling into driver circuitry.  Circuit boards with ground planes are ideal.  You may be able to get away with your existing construction if sufficiently shielded.  Does the gray box contain the driver circuitry (circuitry feeding GDT)?  Is the gray box plastic or metal?  If metal, is the metal connected to ground?

BTW, for white plug-board construction, here's an example of the best I've seen, with short wires flat against the board and bypass capacitors directly between chip power pins:
https://highvoltageforum.net/index.php?topic=1527.msg11899;topicseen#new

Boards with ground planes are still better then even the best-constructed plug-board implementation.
David Knierim

Offline balazs

  • High Voltage Enthusiast
  • *
  • Posts: 27
  • Karma: +0/-0
    • View Profile
Re: gdt high frequency ring
« Reply #32 on: April 20, 2021, 07:29:04 PM »
Thank you for your answers
I shielded the driver, I tied the shadows into the protective earth, the box was plastic. The falls have disappeared from the signal. I tried the coil and it was 1000 W. I tried for about 15 minutes. The strange thing was that the circuit breaker transformer was broken. After that, the coil was still working. Then one of the starts gave no spark and slammed the fuse. This was very strange because so far when the mosfets have burned, I have either started the coil or changed the frequency of the circuit breaker. I noticed a strangeness when measuring the signal. When it is
the spark gets into the grounded part of the secondary coil, the signal at the GDT output is sometimes distorted, which is pretty weird. Cannot be these faults because the outside of the bnc connector transmits the negative signal of the interruption and the protective earth? (positive sign of interrupt runs inside)
I do not tie the secondary to the protective soil.
I would have another question on how to measure the GDT output with 230V operation, because it may not be a good idea to change the oscilloscope to -320V.


« Last Edit: April 20, 2021, 07:31:02 PM by balazs »

Offline davekni

  • High Voltage Expert
  • ******
  • Posts: 1442
  • Karma: +70/-0
  • Physicist, engineer (electronic), and hobbiest
    • View Profile
Re: gdt high frequency ring
« Reply #33 on: April 21, 2021, 06:12:33 AM »
If you are getting sparks down to ground with an SSTC, that is impressive performance.  Do you have a breakout point?  Perhaps aim that away from ground (opposite side of top-load).  Also, either add a ground ring as in DRSSTC designs or back off power a little and enjoy your coil.
David Knierim

Offline balazs

  • High Voltage Enthusiast
  • *
  • Posts: 27
  • Karma: +0/-0
    • View Profile
Re: gdt high frequency ring
« Reply #34 on: April 26, 2021, 09:19:29 PM »
I modify the primer and also add a grounding ring.
How far should I roll the primer from the secondary?
The coil worked pretty well, but I saw a little spark on top of the antenna. Because of this, I placed the annanta a little further away, from where the mosfets deteriorated after a while. How long do I have to place the annanta? What a problem if there is a small spark on the top of the antenna.
Can I connect a 10x 300 V oscilloscope probe to the GDT output and "VBus-" where "320v-" is?



Offline davekni

  • High Voltage Expert
  • ******
  • Posts: 1442
  • Karma: +70/-0
  • Physicist, engineer (electronic), and hobbiest
    • View Profile
Re: gdt high frequency ring
« Reply #35 on: April 27, 2021, 04:33:52 AM »
Since you are not getting arcing from secondary to primary, I'd leave spacing as it is.  No magic answer for perfect primary-to-secondary spacing.

If it works better with the antenna in its original closer position, leave it there.  To reduce corona at the top, make the end rounded, such as forming the end into a loop or adding a small metal sphere to the end.  Just make sure the antenna isn't so close that an arc forms from the secondary top to the antenna.  An insulating sphere can work too, such as drilling a small hole half-way-through a solid rubber ball and sliding the ball over the end of the antenna.

If your scope is battery-powered and not connected to anything else (not to a computer and not touched by a person), then you can scope with the probe "ground" to VBus- (-320V) and tip to gate.  If you measure two signals, the other probe "ground" lead must be to the same VBus- node.

David Knierim

High Voltage Forum

Re: gdt high frequency ring
« Reply #35 on: April 27, 2021, 04:33:52 AM »

 


* Recent Topics and Posts

post Re: Hi! 811 A tesa coil
[Vacuum Tube Tesla Coils (VTTC)]
jpvvv123
Today at 04:13:06 AM
post Re: Self Starting Coil (Not)
[Solid State Tesla Coils (SSTC)]
davekni
Today at 03:34:15 AM
post Self Starting Coil (Not)
[Solid State Tesla Coils (SSTC)]
alan sailer
January 23, 2022, 10:45:46 PM
post Re: GDT Slow Rise/Fall times even with resistor shorted
[Dual Resonant Solid State Tesla coils (DRSSTC)]
davekni
January 23, 2022, 09:06:49 PM
post GDT Slow Rise/Fall times even with resistor shorted
[Dual Resonant Solid State Tesla coils (DRSSTC)]
SalinsLV
January 23, 2022, 07:18:56 PM
post Re: Hi! 811 A tesa coil
[Vacuum Tube Tesla Coils (VTTC)]
304er
January 23, 2022, 06:18:13 PM
post Re: 120VAC Mains Ramped Builds
[Solid State Tesla Coils (SSTC)]
Magneticitist
January 22, 2022, 11:20:55 AM
post Re: 120VAC Mains Ramped Builds
[Solid State Tesla Coils (SSTC)]
ZakW
January 22, 2022, 07:07:09 AM
post Re: GDT Testing
[Solid State Tesla Coils (SSTC)]
johnf
January 22, 2022, 05:27:37 AM
post Re: Help on my "first" SSTC (LabCoatz SSTC 2.0)- Popping transistors
[Solid State Tesla Coils (SSTC)]
davekni
January 22, 2022, 04:27:38 AM
post Re: Hi! 811 A tesa coil
[Vacuum Tube Tesla Coils (VTTC)]
jpvvv123
January 22, 2022, 12:53:04 AM
post Re: 120VAC Mains Ramped Builds
[Solid State Tesla Coils (SSTC)]
Magneticitist
January 21, 2022, 07:36:07 PM
post Re: Muon Decay
[Detection, Counting and Measurements]
Uspring
January 21, 2022, 07:27:23 PM
post Re: Etching PCBs with a SLA 3d printer
[Printed Circuit Board]
TMaxElectronics
January 21, 2022, 02:05:52 PM
post Re: 120VAC Mains Ramped Builds
[Solid State Tesla Coils (SSTC)]
ZakW
January 21, 2022, 09:08:18 AM
post Re: Muon Decay
[Detection, Counting and Measurements]
Da_Stier
January 21, 2022, 08:42:54 AM
post 120VAC Mains Ramped Builds
[Solid State Tesla Coils (SSTC)]
Magneticitist
January 21, 2022, 03:00:04 AM
post Re: Muon Decay
[Detection, Counting and Measurements]
alan sailer
January 21, 2022, 02:16:57 AM
post Re: Help on my "first" SSTC (LabCoatz SSTC 2.0)- Popping transistors
[Solid State Tesla Coils (SSTC)]
TiagoBS
January 20, 2022, 06:56:35 PM
post Re: Muon Decay
[Detection, Counting and Measurements]
Da_Stier
January 20, 2022, 05:19:26 PM
post Re: Muon Decay
[Detection, Counting and Measurements]
alan sailer
January 20, 2022, 03:53:54 PM
post Re: Muon Decay
[Detection, Counting and Measurements]
Uspring
January 20, 2022, 01:20:19 PM
post Re: Muon Decay
[Detection, Counting and Measurements]
Da_Stier
January 20, 2022, 10:11:21 AM
post Re: Muon Decay
[Detection, Counting and Measurements]
alan sailer
January 19, 2022, 08:22:49 PM
post Re: Muon Decay
[Detection, Counting and Measurements]
Mads Barnkob
January 19, 2022, 06:49:36 PM
post Re: Etching PCBs with a SLA 3d printer
[Printed Circuit Board]
hardboiled99
January 19, 2022, 07:37:27 AM
post Primary Coil Winding Technique
[Solid State Tesla Coils (SSTC)]
alan sailer
January 18, 2022, 10:34:48 PM
post Re: Muon Decay
[Detection, Counting and Measurements]
alan sailer
January 18, 2022, 08:46:53 PM
post Re: Muon Decay
[Detection, Counting and Measurements]
Mads Barnkob
January 18, 2022, 08:08:53 PM
post Re: GDT Testing
[Solid State Tesla Coils (SSTC)]
ZakW
January 18, 2022, 07:15:22 PM
post Muon Decay
[Detection, Counting and Measurements]
alan sailer
January 18, 2022, 06:49:48 PM
post Re: Strange reading for grid feedback coil voltage
[Vacuum Tube Tesla Coils (VTTC)]
304er
January 18, 2022, 08:47:53 AM
post Re: QO-100 / EShail 2 Uplink amplifier development adventures
[Radio Frequency]
Da_Stier
January 17, 2022, 09:13:32 PM
post Re: QO-100 / EShail 2 Uplink amplifier development adventures
[Radio Frequency]
Da_Stier
January 17, 2022, 09:05:56 PM
post Re: Help on my "first" SSTC (LabCoatz SSTC 2.0)- Popping transistors
[Solid State Tesla Coils (SSTC)]
Mads Barnkob
January 17, 2022, 07:45:48 PM
post Re: General Questions
[Dual Resonant Solid State Tesla coils (DRSSTC)]
Mads Barnkob
January 17, 2022, 07:41:34 PM
post Re: Strange reading for grid feedback coil voltage
[Vacuum Tube Tesla Coils (VTTC)]
Mads Barnkob
January 17, 2022, 07:38:25 PM
post Re: SSTC with push-pull configuration
[Solid State Tesla Coils (SSTC)]
Mads Barnkob
January 17, 2022, 07:31:03 PM
post Re: GDT Testing
[Solid State Tesla Coils (SSTC)]
Mads Barnkob
January 17, 2022, 07:28:02 PM
post Re: Induction heater Driver for Flyback?
[Voltage Multipliers]
MRMILSTAR
January 16, 2022, 09:00:02 PM
post Induction heater Driver for Flyback?
[Voltage Multipliers]
abstruse1
January 16, 2022, 07:35:26 PM
post Re: SSTC with push-pull configuration
[Solid State Tesla Coils (SSTC)]
Bambinz
January 16, 2022, 12:21:40 PM
post Re: SSTC with push-pull configuration
[Solid State Tesla Coils (SSTC)]
davekni
January 15, 2022, 07:10:03 PM
post Re: SSTC with push-pull configuration
[Solid State Tesla Coils (SSTC)]
Bambinz
January 15, 2022, 06:31:33 PM
post Re: SSTC with push-pull configuration
[Solid State Tesla Coils (SSTC)]
Magneticitist
January 14, 2022, 08:47:43 PM
post Re: SSTC with push-pull configuration
[Solid State Tesla Coils (SSTC)]
davekni
January 14, 2022, 08:39:07 PM
post Re: Unusual Youtube channel activity
[General Chat]
davekni
January 14, 2022, 08:14:17 PM
post Re: Unusual Youtube channel activity
[General Chat]
Mads Barnkob
January 14, 2022, 08:12:13 PM
post Unusual Youtube channel activity
[General Chat]
MRMILSTAR
January 14, 2022, 05:51:52 PM
post Re: Strange reading for grid feedback coil voltage
[Vacuum Tube Tesla Coils (VTTC)]
304er
January 14, 2022, 08:51:57 AM
post Re: SSTC with push-pull configuration
[Solid State Tesla Coils (SSTC)]
Bambinz
January 13, 2022, 08:20:02 PM
post Re: Help with SSTC feedback circuits with 4046 IC and Schmitt Triggers
[Solid State Tesla Coils (SSTC)]
davekni
January 13, 2022, 05:27:40 AM
post Re: General Questions
[Dual Resonant Solid State Tesla coils (DRSSTC)]
thedoc298
January 13, 2022, 03:10:32 AM
post Re: Strange reading for grid feedback coil voltage
[Vacuum Tube Tesla Coils (VTTC)]
304er
January 12, 2022, 06:18:15 PM
post Re: Single mosfet bifiliar gdt
[Solid State Tesla Coils (SSTC)]
alan sailer
January 12, 2022, 05:45:26 PM
post Re: Strange reading for grid feedback coil voltage
[Vacuum Tube Tesla Coils (VTTC)]
MRMILSTAR
January 12, 2022, 03:29:04 PM
post Re: Help with SSTC feedback circuits with 4046 IC and Schmitt Triggers
[Solid State Tesla Coils (SSTC)]
AFreshLad
January 12, 2022, 01:30:38 PM
post Re: Strange reading for grid feedback coil voltage
[Vacuum Tube Tesla Coils (VTTC)]
304er
January 12, 2022, 09:09:13 AM
post Re: Strange reading for grid feedback coil voltage
[Vacuum Tube Tesla Coils (VTTC)]
MRMILSTAR
January 11, 2022, 08:05:27 PM
post Re: Nokia Siemens 3G Flexi 2100MHz 50W Amplifier Teardown
[Radio Frequency]
Mads Barnkob
January 11, 2022, 07:42:12 PM
post Re: Strange reading for grid feedback coil voltage
[Vacuum Tube Tesla Coils (VTTC)]
Duane B
January 11, 2022, 07:33:15 PM
post Re: 8x MOT transformer, weird power draw
[Transformer (Iron Core)]
AstRii
January 11, 2022, 06:19:49 PM
post Re: Strange reading for grid feedback coil voltage
[Vacuum Tube Tesla Coils (VTTC)]
304er
January 11, 2022, 05:19:46 PM
post Re: Strange reading for grid feedback coil voltage
[Vacuum Tube Tesla Coils (VTTC)]
MRMILSTAR
January 11, 2022, 04:31:28 PM
post Re: 8x MOT transformer, weird power draw
[Transformer (Iron Core)]
AstRii
January 11, 2022, 03:21:37 PM
post Re: GDT Testing
[Solid State Tesla Coils (SSTC)]
davekni
January 11, 2022, 06:50:49 AM
post Re: Strange reading for grid feedback coil voltage
[Vacuum Tube Tesla Coils (VTTC)]
Duane B
January 11, 2022, 06:34:20 AM
post Re: Help on my "first" SSTC (LabCoatz SSTC 2.0)- Popping transistors
[Solid State Tesla Coils (SSTC)]
davekni
January 11, 2022, 06:24:13 AM
post Re: Strange reading for grid feedback coil voltage
[Vacuum Tube Tesla Coils (VTTC)]
davekni
January 11, 2022, 06:15:08 AM
post Re: Strange reading for grid feedback coil voltage
[Vacuum Tube Tesla Coils (VTTC)]
MRMILSTAR
January 11, 2022, 05:25:31 AM
post Re: Strange reading for grid feedback coil voltage
[Vacuum Tube Tesla Coils (VTTC)]
Duane B
January 11, 2022, 12:07:22 AM
post Strange reading for grid feedback coil voltage
[Vacuum Tube Tesla Coils (VTTC)]
MRMILSTAR
January 10, 2022, 10:56:48 PM
post Re: Hi! 811 A tesa coil
[Vacuum Tube Tesla Coils (VTTC)]
Duane B
January 10, 2022, 09:38:53 PM
post Re: Help on my "first" SSTC (LabCoatz SSTC 2.0)- Popping transistors
[Solid State Tesla Coils (SSTC)]
ZakW
January 10, 2022, 07:50:13 PM
post Re: GDT Testing
[Solid State Tesla Coils (SSTC)]
ZakW
January 10, 2022, 07:19:17 PM
post Re: Help on my "first" SSTC (LabCoatz SSTC 2.0)- Popping transistors
[Solid State Tesla Coils (SSTC)]
TiagoBS
January 10, 2022, 03:13:08 PM
post Re: GDT Testing
[Solid State Tesla Coils (SSTC)]
davekni
January 10, 2022, 04:21:46 AM
post Re: Hi! 811 A tesa coil
[Vacuum Tube Tesla Coils (VTTC)]
304er
January 10, 2022, 03:59:09 AM
post Re: 8x MOT transformer, weird power draw
[Transformer (Iron Core)]
davekni
January 10, 2022, 03:54:59 AM
post Re: GDT Testing
[Solid State Tesla Coils (SSTC)]
ZakW
January 09, 2022, 11:45:09 PM
post Re: Hi! 811 A tesa coil
[Vacuum Tube Tesla Coils (VTTC)]
jpvvv123
January 09, 2022, 11:04:25 PM
post 8x MOT transformer, weird power draw
[Transformer (Iron Core)]
AstRii
January 09, 2022, 04:22:11 PM
post Re: Hi! 811 A tesa coil
[Vacuum Tube Tesla Coils (VTTC)]
Duane B
January 09, 2022, 05:52:11 AM
post Re: GDT Testing
[Solid State Tesla Coils (SSTC)]
davekni
January 09, 2022, 05:10:50 AM
post Re: Performance issues regarding phase angle in SSTCs
[Solid State Tesla Coils (SSTC)]
davekni
January 09, 2022, 01:20:40 AM
post GDT Testing
[Solid State Tesla Coils (SSTC)]
ZakW
January 09, 2022, 12:38:28 AM
post Re: General Questions
[Dual Resonant Solid State Tesla coils (DRSSTC)]
flyingperson23
January 08, 2022, 06:36:28 PM
post Performance issues regarding phase angle in SSTCs
[Solid State Tesla Coils (SSTC)]
Max Seiringer
January 08, 2022, 03:21:31 PM
post Re: Hi! 811 A tesa coil
[Vacuum Tube Tesla Coils (VTTC)]
304er
January 08, 2022, 09:05:41 AM
post Re: Hi! 811 A tesa coil
[Vacuum Tube Tesla Coils (VTTC)]
jpvvv123
January 07, 2022, 10:20:10 PM
post Re: Hi! 811 A tesa coil
[Vacuum Tube Tesla Coils (VTTC)]
304er
January 07, 2022, 05:56:28 PM
post Re: First SSTC based on profdc9 PCB Pack
[Solid State Tesla Coils (SSTC)]
davekni
January 07, 2022, 05:15:38 AM
post Re: DRSSTC tuning
[Dual Resonant Solid State Tesla coils (DRSSTC)]
davekni
January 07, 2022, 05:01:21 AM
post Re: How to prevent secondary to secondary to primary arcs?
[Dual Resonant Solid State Tesla coils (DRSSTC)]
davekni
January 07, 2022, 04:59:59 AM
post Tophat QCW 1
[Dual Resonant Solid State Tesla coils (DRSSTC)]
dbach
January 07, 2022, 02:27:35 AM
post How to prevent secondary to secondary to primary arcs?
[Dual Resonant Solid State Tesla coils (DRSSTC)]
dbach
January 07, 2022, 02:19:40 AM
post Re: General Questions
[Dual Resonant Solid State Tesla coils (DRSSTC)]
Mads Barnkob
January 06, 2022, 09:33:06 PM
post Re: First SSTC based on profdc9 PCB Pack
[Solid State Tesla Coils (SSTC)]
alan sailer
January 06, 2022, 06:09:39 PM
post Re: DRSSTC tuning
[Dual Resonant Solid State Tesla coils (DRSSTC)]
kubajed
January 06, 2022, 04:48:22 PM
post Re: First SSTC based on profdc9 PCB Pack
[Solid State Tesla Coils (SSTC)]
SK1701
January 06, 2022, 03:05:55 PM

Sitemap 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 
SimplePortal 2.3.6 © 2008-2014, SimplePortal