Author Topic: Aluminum electrolytic capacitor ripple current issue  (Read 726 times)

Offline NyaaX_X

  • High Voltage Technician
  • ***
  • Posts: 124
  • Karma: +2/-0
    • View Profile
Aluminum electrolytic capacitor ripple current issue
« on: May 07, 2024, 06:07:48 AM »
Hello everyone.

I am working at a wireless power transfer circuit. And there we full-bridge rectifie the Rx ~128kHz AC signal. Pass through a P-mos ideal diode circuit, then we have 1x 100uF aluminum elelctrolytic capacitor parallel with 3x X5R--22uF mlcc, 1x X5R--10uF mlcc, 1x X7R--0.1uF mlcc. As the filter capactors @ ~16V. Then power the after stage.

We measured the ripple current of the E-cap. With extra lead wire and clamp probe. It seems the ripple current is over the rated current. So, we change that E-Cap to a hybrid polymer, 100uF Aluminum E-Cap as replacement.

The old one has a larger capacitance decay and larger ESR at this frequency compares to the new hybrid one. But the new one shows the more higher temperature increase when working with SMT two leads soldering on board pads. And more ripple current when we clamp measure it (ripple current freq. is 256kHz)

So, I am considering if it is going to the self-resonance or anti-resonance situation, caused that larger ripple current and temp-increase.(The on board ripple voltage peak to peak is ~150mV, the clamping test is ~410mV, ripple current ~800mA,rms)

Is that possible? Or the other reasons there? If so, How can I determine them?

Thank you~
« Last Edit: May 07, 2024, 06:11:25 AM by NyaaX_X »

Offline Twospoons

  • High Voltage Engineer
  • ****
  • Posts: 235
  • Karma: +6/-0
    • View Profile
Re: Aluminum electrolytic capacitor ripple current issue
« Reply #1 on: May 08, 2024, 06:41:48 AM »
One more thing to check is the switching of your pmos ideal diode - if the phasing is wrong then you would see higher than expected ripple current.  As a test, you could replace it with a schottky diode, then recheck your ripple current.


Offline NyaaX_X

  • High Voltage Technician
  • ***
  • Posts: 124
  • Karma: +2/-0
    • View Profile
Re: Aluminum electrolytic capacitor ripple current issue
« Reply #2 on: May 08, 2024, 01:31:28 PM »
Thank you Twospoons for the replying.

But what is causing the different phasing as you say? We use two type of E-Cap and only one shows the obvious larger ripple.

Ah- I might describe not clearly. The wireless ~128k AC signal --> MOSFETs full-bridge rectifer --> P-mos ideal diode (P-mos, current mirror with discrete components, not ideal diode controller) --> E-CAP 100uF//MLCC 22uF//MLCC 22uF//MLCC 22uF//MLCC 10uF//MLCC 0.1uF --> post-stage (MCU/ D-D power/ etc.)
« Last Edit: May 08, 2024, 04:00:24 PM by NyaaX_X »

Offline davekni

  • Executive Board Member
  • *******
  • Posts: 2799
  • Karma: +133/-1
  • Physicist, engineer (electronic), and hobbiest
    • View Profile
Re: Aluminum electrolytic capacitor ripple current issue
« Reply #3 on: May 09, 2024, 03:56:52 AM »
Likely several issues. Wire loop for current measurement probably alters circuit operation.  Current probes are likely to be susceptible to fields from wireless charging coil.  Usually best to measure voltage and calculate current based on capacitor impedance (C and ESR).  Typical ESR for new electrolytic caps is about half of worst-case specification.  Measuring voltage accurately also requires good technique.  Use small-diameter coax or twisted pair soldered to bypass capacitor.  Connect to scope (or scope probe) only once far from charging coil.

At 256kHz ripple current should be mostly in ceramic caps.  Bulk (electrolytic) cap is mostly for loop stability and to handle load transients.  I'd guess your ceramic caps aren't very good at operating voltage.  Many drop by 90% of rated capacitance at rated DC voltage.  Some large suppliers such as Murata and TDK publish at least typical curves for their ceramic caps.  Takes work searching, but find caps that are good at your use voltage.

Circuit layout could also be contributing to excess ripple.

Run LTSpice simulation.  If ripple voltage is far from simulated value, then look for PFET cross-conduction or other such issues.
David Knierim

Offline NyaaX_X

  • High Voltage Technician
  • ***
  • Posts: 124
  • Karma: +2/-0
    • View Profile
Re: Aluminum electrolytic capacitor ripple current issue
« Reply #4 on: May 09, 2024, 09:15:24 AM »
Thank you Dave,

We tested the ripple voltage on PCB. For the Hybrid E-Cap, the Ripple Vpp is lower then the classic one... The main issue is.. If we just check the Temp. of them. The new one have the more Temp. increasing compared to the old one. Even the less V ripple of it. But as Spec. the ESR and high frequency capacitance decay of the new one is better than the old one.

Here is the compare. Vpp I use twisted OK wire to measure them.
And yes, the 22uF and 10uF MLCC now using the X5R...@~15V, rated 25V

Old (Chemicon MZR 100uF, ESR 260mohm@100kHz)
Final Temp ~52°C, Vpp ripple on PCB ~250mV, and Vpp ripple when clamping is ~300mV, Ipp ~400mA

New (Chemicon HXJ 100uF, ESR 50mohm@100kHz)
Final Temp ~65°C, Vpp ripple on PCB ~150mV, and Vpp ripple when clampling is ~410mV, Ipp ~800mA

Well.. I guess our circuit is not quite healthy.. For load transient changing like starting up... Sad
« Last Edit: May 09, 2024, 09:26:49 AM by NyaaX_X »

Offline klugesmith

  • High Voltage Senior
  • *****
  • Posts: 707
  • Karma: +22/-0
    • View Profile
Re: Aluminum electrolytic capacitor ripple current issue
« Reply #5 on: May 09, 2024, 06:59:22 PM »
Is this for a hobby project or a commercial design?

Offline Twospoons

  • High Voltage Engineer
  • ****
  • Posts: 235
  • Karma: +6/-0
    • View Profile
Re: Aluminum electrolytic capacitor ripple current issue
« Reply #6 on: May 10, 2024, 12:06:50 AM »

But what is causing the different phasing as you say? We use two type of E-Cap and only one shows the obvious larger ripple.


I meant the relative phase between the switching of your MOS rectifiers and the signal you are rectifying. For example, slow turn off would result in current flowing back to the pick-up coil, and therefore higher ripple in your caps.

As I said - try it with schottky diodes and see what happens.

Also your 25V MLCC caps running at 15V will be at about 40% of rated value.   Murata have a useful tool for this stuff https://ds.murata.co.jp/simsurfing/index.html?lcid=en-us

Offline davekni

  • Executive Board Member
  • *******
  • Posts: 2799
  • Karma: +133/-1
  • Physicist, engineer (electronic), and hobbiest
    • View Profile
Re: Aluminum electrolytic capacitor ripple current issue
« Reply #7 on: May 10, 2024, 01:39:53 AM »
Quote
Murata have a useful tool for this stuff https://ds.murata.co.jp/simsurfing/index.html?lcid=en-us
Yes, nice tools from some of the larger suppliers.

Quote
Also your 25V MLCC caps running at 15V will be at about 40% of rated value.
I've seen much worse even from reputable suppliers.  Just looked at that tool for 22uF 25V X5S parts.  Only one showed up: GRM188C61E226ME01.  It drops to 10% of rated value by 15V.
David Knierim

Offline Twospoons

  • High Voltage Engineer
  • ****
  • Posts: 235
  • Karma: +6/-0
    • View Profile
Re: Aluminum electrolytic capacitor ripple current issue
« Reply #8 on: May 10, 2024, 03:02:13 AM »
Yeah, its a "gotcha" that traps fresh graduate EEs all the time.

Offline NyaaX_X

  • High Voltage Technician
  • ***
  • Posts: 124
  • Karma: +2/-0
    • View Profile
Re: Aluminum electrolytic capacitor ripple current issue
« Reply #9 on: May 11, 2024, 06:40:50 AM »
Yes,
Like this mlcc, the TDK products page shows the frequency/bias relation measurement plot in for each part.
https://product.tdk.com/en/search/capacitor/ceramic/mlcc/info?part_no=C2012X5R1E226M125AC

But I think the issue of different is between the two type of aluminum electrolytic capacitors, they have same package, same capcitance (but diffierent decay under frequency changing), same voltage rated. And the only changing to the circuit is these capacitors for these days question.

The two problems are:

(1)_I measured the ripple voltage cross to the E-CAP when they were soldered on PCB on pads. The hybrid one shows a lower ripple voltage compared to the original one, but the ΔTemp after few hours running of the Hybrid one is greater than the original one.

(2)_And if I connect a lead wire and clamp-measure them (same lead wire, and both of these two types are soldered with (-) on PCB pad. The clamp probe did affect the behaviors a few. And the result is hybrid one Vripple increase is more bigger compares to the original one.

I am only curious about the changing of this one E-Cap make the issue.

Thank you everyone~

Offline davekni

  • Executive Board Member
  • *******
  • Posts: 2799
  • Karma: +133/-1
  • Physicist, engineer (electronic), and hobbiest
    • View Profile
Re: Aluminum electrolytic capacitor ripple current issue
« Reply #10 on: May 12, 2024, 10:56:53 PM »
Look back at reply 1 from Twospoons and first paragraph of reply 3 (mine), considering that ceramic caps are ~2uF rather than 22uF.  There is little value in providing more advice until you try the good advice already provided.
David Knierim

Offline NyaaX_X

  • High Voltage Technician
  • ***
  • Posts: 124
  • Karma: +2/-0
    • View Profile
Re: Aluminum electrolytic capacitor ripple current issue
« Reply #11 on: May 13, 2024, 02:25:25 AM »
Actually, I do have apply a Sch diode SS34-1n5822 at that p-mos placing. The ripple voltage on that E-cap change from 150mV-->~137mV. And the E-Cap still heating up significantly. I am looking for the using experience of this kind of capacitors.

And for MLCC, I need to find the replacement later...

Thanks

Offline davekni

  • Executive Board Member
  • *******
  • Posts: 2799
  • Karma: +133/-1
  • Physicist, engineer (electronic), and hobbiest
    • View Profile
Re: Aluminum electrolytic capacitor ripple current issue
« Reply #12 on: May 13, 2024, 05:02:46 AM »
Quote
Actually, I do have apply a Sch diode SS34-1n5822 at that p-mos placing.
Did you replace both PMOS devices?

Quote
The ripple voltage on that E-cap change from 150mV-->~137mV.
What current did you calculate from that ripple voltage?
David Knierim

Offline NyaaX_X

  • High Voltage Technician
  • ***
  • Posts: 124
  • Karma: +2/-0
    • View Profile
Re: Aluminum electrolytic capacitor ripple current issue
« Reply #13 on: May 13, 2024, 07:09:16 AM »
OK, using 10X probe, I apply SCH diode to original one and hybrid one,

MZR series max ESR = 0.3ohm at 100kHz,
I get AC rms of 0.06824 mV --> / 0.3 = 0.2274 Arms Iripple


And HXJ series max ESR = 0.05ohm at 100kHz, but 256kHz is nearing its self-resonance Freq.
I get AC rms of V ripple = 0.02468mV --> / 0.05 = 0.4936 Arms Iripple
« Last Edit: May 16, 2024, 06:06:30 AM by NyaaX_X »

Offline davekni

  • Executive Board Member
  • *******
  • Posts: 2799
  • Karma: +133/-1
  • Physicist, engineer (electronic), and hobbiest
    • View Profile
Re: Aluminum electrolytic capacitor ripple current issue
« Reply #14 on: May 16, 2024, 04:36:40 AM »
Quote
OK, using 10X prove, I apply SCH diode to original one and hybrid one,
Did you remove FETs when adding diodes?  If not, any possible cross-conduction issue may still exist.

Quote
MZR series max ESR = 0.3ohm at 100kHz,
I get AC rms of 0.06824 mV --> / 0.3 = 0.2274 Arms Iripple
As I'd mentioned before, typical initial ESR is around half of specification.  Current is likely about twice above value.

What current do you expect (from simulation or a rough estimate based on DC load current)?
David Knierim

Offline NyaaX_X

  • High Voltage Technician
  • ***
  • Posts: 124
  • Karma: +2/-0
    • View Profile
Re: Aluminum electrolytic capacitor ripple current issue
« Reply #15 on: May 16, 2024, 06:00:49 AM »
Hello Dave,

Yes I have removed the p-mos.

These days I am simulating the simplified circuit in LTspice, some of the result ia close to the real circuit. But I still trying the different parameters. Later I will put the file here.

I was considering the lower ESR, the larger capacitance of capacitor could decrease the ripple. But it seems the appropriately of ESR could suppress them better? I have no idea...
« Last Edit: May 16, 2024, 06:11:53 AM by NyaaX_X »

Offline NyaaX_X

  • High Voltage Technician
  • ***
  • Posts: 124
  • Karma: +2/-0
    • View Profile
Re: Aluminum electrolytic capacitor ripple current issue
« Reply #16 on: May 16, 2024, 05:04:41 PM »
I made a simulation. Here is the LTspice file.

For the bridge FETs, I picked one kind in the lib randomly. And the rectifier FETs I use Schottky diodes as replacements. So do the ideal diode.

I try to make a guess of the two kinds of electrolytic capacitor, parameters for them. So, please have a look in your free time~

Thanks!!

Offline davekni

  • Executive Board Member
  • *******
  • Posts: 2799
  • Karma: +133/-1
  • Physicist, engineer (electronic), and hobbiest
    • View Profile
Re: Aluminum electrolytic capacitor ripple current issue
« Reply #17 on: May 16, 2024, 06:54:05 PM »
Update design in simulation until capacitor currents are all within part specifications with margin (with currents a ways below max rating).  Measure ceramic capacitor values at operating DC voltage to obtain accurate values to use in simulation, or at least use the manufacturer's c/v curves to estimate.
David Knierim

High Voltage Forum

Re: Aluminum electrolytic capacitor ripple current issue
« Reply #17 on: May 16, 2024, 06:54:05 PM »

 


* Recent Topics and Posts

post Re: Pulse Power High Current Discharges from 3 Phase PFC Capacitors
[Capacitor Banks]
MRMILSTAR
Today at 05:22:43 AM
post Re: Want to build HV HF oscilloscope probe.
[Electronic Circuits]
Twospoons
Today at 05:08:46 AM
post Re: Pulse Power High Current Discharges from 3 Phase PFC Capacitors
[Capacitor Banks]
davekni
Today at 04:49:16 AM
post Re: Ring Launcher AC vs DC?
[Induction Launchers, Coil Guns and Rails guns]
FPS
Today at 03:55:37 AM
post Re: Want to build HV HF oscilloscope probe.
[Electronic Circuits]
klugesmith
Today at 02:48:22 AM
post Re: Want to build HV HF oscilloscope probe.
[Electronic Circuits]
Domo
Today at 02:05:05 AM
post Re: Plasma Torid - Class E Self Resonant Dual/Stereo - Plasma Torid Build
[Dual Resonant Solid State Tesla coils (DRSSTC)]
alan sailer
Today at 01:43:10 AM
post Re: Want to build HV HF oscilloscope probe.
[Electronic Circuits]
Twospoons
May 18, 2024, 11:30:11 PM
post Re: Pulse Power High Current Discharges from 3 Phase PFC Capacitors
[Capacitor Banks]
MRMILSTAR
May 18, 2024, 10:10:56 PM
post Want to build HV HF oscilloscope probe.
[Electronic Circuits]
Domo
May 18, 2024, 09:46:17 PM
post Re: Pulse Power High Current Discharges from 3 Phase PFC Capacitors
[Capacitor Banks]
davekni
May 18, 2024, 08:05:36 PM
post Re: Help an EE student
[General Chat]
Twospoons
May 18, 2024, 05:59:21 AM
post Re: What capacitor configuration to explode foil?
[Capacitor Banks]
MRMILSTAR
May 18, 2024, 05:44:41 AM
post Re: RDRSSTC - Project Build
[Dual Resonant Solid State Tesla coils (DRSSTC)]
ZakW
May 18, 2024, 01:55:42 AM
post Re: What capacitor configuration to explode foil?
[Capacitor Banks]
klugesmith
May 17, 2024, 11:49:33 PM
post Re: Pulse Power High Current Discharges from 3 Phase PFC Capacitors
[Capacitor Banks]
MRMILSTAR
May 17, 2024, 10:18:46 PM
post Pulse Power High Current Discharges from 3 Phase PFC Capacitors
[Capacitor Banks]
Mads Barnkob
May 17, 2024, 07:24:22 PM
post Re: What capacitor configuration to explode foil?
[Capacitor Banks]
Mads Barnkob
May 17, 2024, 07:14:35 PM
post Re: Help an EE student
[General Chat]
Mads Barnkob
May 17, 2024, 08:35:38 AM
post Re: Help an EE student
[General Chat]
MRMILSTAR
May 17, 2024, 05:34:10 AM
post Re: colored 50 Ohm coax
[General Chat]
Da_Stier
May 16, 2024, 10:53:53 PM
post Re: Help an EE student
[General Chat]
Michelle_
May 16, 2024, 10:37:50 PM
post Re: Help an EE student
[General Chat]
davekni
May 16, 2024, 10:29:30 PM
post Re: Help an EE student
[General Chat]
klugesmith
May 16, 2024, 08:26:41 PM
post Re: Aluminum electrolytic capacitor ripple current issue
[Beginners]
davekni
May 16, 2024, 06:54:05 PM
post Re: Aluminum electrolytic capacitor ripple current issue
[Beginners]
NyaaX_X
May 16, 2024, 05:04:41 PM
post Re: Tesla Synth Player for Syntherrupter
[Computers, Microcontrollers, Programmable Logic, Interfaces and Displays]
AntoineRcbs
May 16, 2024, 12:13:47 PM
post Re: Help with primary voltages of unknown transformer
[Transformer (Ferrite Core)]
Domo
May 16, 2024, 06:58:12 AM
post Re: New EE student asks about Cutting-Edge fields
[General Chat]
davekni
May 16, 2024, 06:47:09 AM
post Re: Aluminum electrolytic capacitor ripple current issue
[Beginners]
NyaaX_X
May 16, 2024, 06:00:49 AM
post Re: New EE student asks about Cutting-Edge fields
[General Chat]
Twospoons
May 16, 2024, 05:45:08 AM
post Re: New EE student asks about Cutting-Edge fields
[General Chat]
davekni
May 16, 2024, 05:03:41 AM
post Re: DRSSTC grounding issues
[Dual Resonant Solid State Tesla coils (DRSSTC)]
davekni
May 16, 2024, 04:58:40 AM
post Re: Aluminum electrolytic capacitor ripple current issue
[Beginners]
davekni
May 16, 2024, 04:36:40 AM
post Re: colored 50 Ohm coax
[General Chat]
klugesmith
May 16, 2024, 12:28:27 AM
post Re: Watercooling
[Dual Resonant Solid State Tesla coils (DRSSTC)]
acobaugh
May 15, 2024, 11:13:48 PM
post Re: Help with primary voltages of unknown transformer
[Transformer (Ferrite Core)]
klugesmith
May 15, 2024, 10:58:05 PM
post colored 50 Ohm coax
[General Chat]
Da_Stier
May 15, 2024, 08:31:48 PM
post Re: DRSSTC grounding issues
[Dual Resonant Solid State Tesla coils (DRSSTC)]
Mads Barnkob
May 15, 2024, 07:56:38 PM
post Re: DRSSTC grounding issues
[Dual Resonant Solid State Tesla coils (DRSSTC)]
flyingperson23
May 15, 2024, 06:29:59 PM
post Re: Watercooling
[Dual Resonant Solid State Tesla coils (DRSSTC)]
Felix B.
May 15, 2024, 04:04:14 PM
post Re: Schmitt trigger schematic question
[Electronic Circuits]
Michelle_
May 15, 2024, 03:32:57 PM
post DRSSTC grounding issues
[Dual Resonant Solid State Tesla coils (DRSSTC)]
Felix B.
May 15, 2024, 03:07:39 PM
post New EE student asks about Cutting-Edge fields
[General Chat]
samsonwilliams
May 15, 2024, 05:50:59 AM
post Re: Help with primary voltages of unknown transformer
[Transformer (Ferrite Core)]
Domo
May 15, 2024, 05:38:14 AM
post Re: Schmitt trigger schematic question
[Electronic Circuits]
Benjamin Lockhart
May 15, 2024, 04:58:02 AM
post Re: Big Coil Build Log
[Dual Resonant Solid State Tesla coils (DRSSTC)]
flyingperson23
May 15, 2024, 04:34:49 AM
post Re: Watercooling
[Dual Resonant Solid State Tesla coils (DRSSTC)]
flyingperson23
May 15, 2024, 04:30:18 AM
post Re: Watercooling
[Dual Resonant Solid State Tesla coils (DRSSTC)]
Benjamin Lockhart
May 15, 2024, 04:00:55 AM
post Re: Watercooling
[Dual Resonant Solid State Tesla coils (DRSSTC)]
flyingperson23
May 15, 2024, 03:21:51 AM
post Re: Schmitt trigger schematic question
[Electronic Circuits]
Michelle_
May 14, 2024, 11:12:22 PM
post Re: Schmitt trigger schematic question
[Electronic Circuits]
Benjamin Lockhart
May 14, 2024, 11:00:00 PM
post Schmitt trigger schematic question
[Electronic Circuits]
Michelle_
May 14, 2024, 09:45:38 PM
post Re: Help with primary voltages of unknown transformer
[Transformer (Ferrite Core)]
klugesmith
May 14, 2024, 09:02:28 PM
post Re: Small-ish 3D printed SGTC via cheap ZVS flyback build, humbly asking a couple ?s
[Spark Gap Tesla Coils (SGTC)]
Michelle_
May 14, 2024, 05:55:24 AM
post Re: Weird AC/DC mini SSTC build review
[Solid State Tesla Coils (SSTC)]
Michelle_
May 14, 2024, 05:44:12 AM
post Re: Small-ish 3D printed SGTC via cheap ZVS flyback build, humbly asking a couple ?s
[Spark Gap Tesla Coils (SGTC)]
MRMILSTAR
May 14, 2024, 05:11:54 AM
post Re: Help with primary voltages of unknown transformer
[Transformer (Ferrite Core)]
alan sailer
May 13, 2024, 11:44:56 PM
post Re: Help with primary voltages of unknown transformer
[Transformer (Ferrite Core)]
Domo
May 13, 2024, 10:28:34 PM
post Re: Help with primary voltages of unknown transformer
[Transformer (Ferrite Core)]
alan sailer
May 13, 2024, 10:20:19 PM
post Re: Help with primary voltages of unknown transformer
[Transformer (Ferrite Core)]
Domo
May 13, 2024, 09:27:58 PM
post Re: Help with primary voltages of unknown transformer
[Transformer (Ferrite Core)]
alan sailer
May 13, 2024, 09:06:59 PM
post Help with primary voltages of unknown transformer
[Transformer (Ferrite Core)]
Domo
May 13, 2024, 08:43:49 PM
post Re: Benjamin's DRSSTC 2 in progress
[Dual Resonant Solid State Tesla coils (DRSSTC)]
Benjamin Lockhart
May 13, 2024, 07:25:29 PM
post Re: Plasma Torid - Class E Self Resonant Dual/Stereo - Plasma Torid Build
[Dual Resonant Solid State Tesla coils (DRSSTC)]
OmGigaTron
May 13, 2024, 06:50:59 PM
post Re: Weird AC/DC mini SSTC build review
[Solid State Tesla Coils (SSTC)]
Michelle_
May 13, 2024, 03:47:08 PM
post Re: Small-ish 3D printed SGTC via cheap ZVS flyback build, humbly asking a couple ?s
[Spark Gap Tesla Coils (SGTC)]
Michelle_
May 13, 2024, 03:42:58 PM
post Re: Aluminum electrolytic capacitor ripple current issue
[Beginners]
NyaaX_X
May 13, 2024, 07:09:16 AM
post Re: Aluminum electrolytic capacitor ripple current issue
[Beginners]
davekni
May 13, 2024, 05:02:46 AM
post Re: Aluminum electrolytic capacitor ripple current issue
[Beginners]
NyaaX_X
May 13, 2024, 02:25:25 AM
post Re: Plasma Torid - Class E Self Resonant Dual/Stereo - Plasma Torid Build
[Dual Resonant Solid State Tesla coils (DRSSTC)]
alan sailer
May 13, 2024, 01:39:11 AM
post Re: Plasma Toroid
[Solid State Tesla Coils (SSTC)]
alan sailer
May 13, 2024, 01:33:21 AM
post Re: Aluminum electrolytic capacitor ripple current issue
[Beginners]
davekni
May 12, 2024, 10:56:53 PM
post Re: Quick question about steve ward mini SST5 resonant frequency
[Solid State Tesla Coils (SSTC)]
NyaaX_X
May 12, 2024, 05:10:40 PM
post Re: Help with LabCoatz's Staccato QCW DRSSTC Tesla Coil
[Beginners]
Michelle_
May 12, 2024, 04:24:44 PM
post Re: Help with LabCoatz's Staccato QCW DRSSTC Tesla Coil
[Beginners]
alan sailer
May 12, 2024, 04:10:54 PM
post Re: Help with LabCoatz's Staccato QCW DRSSTC Tesla Coil
[Beginners]
Michelle_
May 12, 2024, 04:04:11 PM
post Re: Help with LabCoatz's Staccato QCW DRSSTC Tesla Coil
[Beginners]
hal7rr
May 12, 2024, 03:56:57 PM
post Re: Help with LabCoatz's Staccato QCW DRSSTC Tesla Coil
[Beginners]
Michelle_
May 12, 2024, 03:46:45 PM
post Re: Help with LabCoatz's Staccato QCW DRSSTC Tesla Coil
[Beginners]
hal7rr
May 12, 2024, 02:59:16 PM
post Re: Quick question about steve ward mini SST5 resonant frequency
[Solid State Tesla Coils (SSTC)]
Michelle_
May 12, 2024, 02:51:27 PM
post Re: Help with LabCoatz's Staccato QCW DRSSTC Tesla Coil
[Beginners]
Michelle_
May 12, 2024, 02:49:42 PM
post Re: Quick question about steve ward mini SST5 resonant frequency
[Solid State Tesla Coils (SSTC)]
ZakW
May 12, 2024, 08:34:39 AM
post Re: Help with LabCoatz's Staccato QCW DRSSTC Tesla Coil
[Beginners]
ZakW
May 12, 2024, 08:30:29 AM
post Re: Help with LabCoatz's Staccato QCW DRSSTC Tesla Coil
[Beginners]
Michelle_
May 12, 2024, 02:35:17 AM
post Re: Help with LabCoatz's Staccato QCW DRSSTC Tesla Coil
[Beginners]
alan sailer
May 12, 2024, 02:07:32 AM
post Re: Help with LabCoatz's Staccato QCW DRSSTC Tesla Coil
[Beginners]
Michelle_
May 11, 2024, 09:55:59 PM
post Re: Help with LabCoatz's Staccato QCW DRSSTC
[Beginners]
NyaaX_X
May 11, 2024, 06:16:22 PM
post Help with LabCoatz's Staccato QCW DRSSTC Tesla Coil
[Beginners]
hal7rr
May 11, 2024, 05:24:34 PM
post Re: Type 77 Metglas Laced Ferrite Core
[General Chat]
NyaaX_X
May 11, 2024, 10:39:24 AM
post Re: Type 77 Metglas Laced Ferrite Core
[General Chat]
Mads Barnkob
May 11, 2024, 07:02:20 AM
post Re: Aluminum electrolytic capacitor ripple current issue
[Beginners]
NyaaX_X
May 11, 2024, 06:40:50 AM
post Type 77 Metglas Laced Ferrite Core
[General Chat]
paulp1776
May 11, 2024, 06:23:59 AM
post Re: Weird AC/DC mini SSTC build review
[Solid State Tesla Coils (SSTC)]
Michelle_
May 11, 2024, 05:27:22 AM
post Re: Quick question about steve ward mini SST5 resonant frequency
[Solid State Tesla Coils (SSTC)]
alan sailer
May 11, 2024, 01:37:37 AM
post Re: designing and building electron gun help!
[General Chat]
Twospoons
May 11, 2024, 12:10:44 AM
post designing and building electron gun help!
[General Chat]
Luca c.
May 10, 2024, 09:38:05 PM
post Re: Quick question about steve ward mini SST5 resonant frequency
[Solid State Tesla Coils (SSTC)]
Michelle_
May 10, 2024, 09:24:21 PM
post Re: Quick question about steve ward mini SST5 resonant frequency
[Solid State Tesla Coils (SSTC)]
alan sailer
May 10, 2024, 08:43:11 PM
post Quick question about steve ward mini SST5 resonant frequency
[Solid State Tesla Coils (SSTC)]
Michelle_
May 10, 2024, 08:33:47 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